diff --git a/Library/Homebrew/test/ENV_spec.rb b/Library/Homebrew/test/ENV_spec.rb
index 7106fd4311..ec2aae5773 100644
--- a/Library/Homebrew/test/ENV_spec.rb
+++ b/Library/Homebrew/test/ENV_spec.rb
@@ -2,7 +2,7 @@
 
 require "extend/ENV"
 
-describe "ENV" do
+RSpec.describe "ENV" do
   shared_examples EnvActivation do
     subject(:env) { env_activation.extend(described_class) }
 
diff --git a/Library/Homebrew/test/PATH_spec.rb b/Library/Homebrew/test/PATH_spec.rb
index e9eedcee91..f21fcac32f 100644
--- a/Library/Homebrew/test/PATH_spec.rb
+++ b/Library/Homebrew/test/PATH_spec.rb
@@ -2,7 +2,7 @@
 
 require "PATH"
 
-describe PATH do
+RSpec.describe PATH do
   describe "#initialize" do
     it "can take multiple arguments" do
       expect(described_class.new("/path1", "/path2")).to eq("/path1:/path2")
diff --git a/Library/Homebrew/test/api/cask_spec.rb b/Library/Homebrew/test/api/cask_spec.rb
index 8ab701a9d8..6758e1671c 100644
--- a/Library/Homebrew/test/api/cask_spec.rb
+++ b/Library/Homebrew/test/api/cask_spec.rb
@@ -2,7 +2,7 @@
 
 require "api"
 
-describe Homebrew::API::Cask do
+RSpec.describe Homebrew::API::Cask do
   let(:cache_dir) { mktmpdir }
 
   before do
diff --git a/Library/Homebrew/test/api/formula_spec.rb b/Library/Homebrew/test/api/formula_spec.rb
index e0ed230ae5..49a3101064 100644
--- a/Library/Homebrew/test/api/formula_spec.rb
+++ b/Library/Homebrew/test/api/formula_spec.rb
@@ -2,7 +2,7 @@
 
 require "api"
 
-describe Homebrew::API::Formula do
+RSpec.describe Homebrew::API::Formula do
   let(:cache_dir) { mktmpdir }
 
   before do
diff --git a/Library/Homebrew/test/api_spec.rb b/Library/Homebrew/test/api_spec.rb
index 4b6c121c69..e8b7fee401 100644
--- a/Library/Homebrew/test/api_spec.rb
+++ b/Library/Homebrew/test/api_spec.rb
@@ -2,7 +2,7 @@
 
 require "api"
 
-describe Homebrew::API do
+RSpec.describe Homebrew::API do
   let(:text) { "foo" }
   let(:json) { '{"foo":"bar"}' }
   let(:json_hash) { JSON.parse(json) }
diff --git a/Library/Homebrew/test/bash_spec.rb b/Library/Homebrew/test/bash_spec.rb
index 79984e8ff9..9a23d1dc29 100644
--- a/Library/Homebrew/test/bash_spec.rb
+++ b/Library/Homebrew/test/bash_spec.rb
@@ -2,7 +2,7 @@
 
 require "open3"
 
-describe "Bash" do
+RSpec.describe "Bash" do
   matcher :have_valid_bash_syntax do
     match do |file|
       stdout, stderr, status = Open3.capture3("/bin/bash", "-n", file)
diff --git a/Library/Homebrew/test/bottle_filename_spec.rb b/Library/Homebrew/test/bottle_filename_spec.rb
index c8e7a27591..af036384ab 100644
--- a/Library/Homebrew/test/bottle_filename_spec.rb
+++ b/Library/Homebrew/test/bottle_filename_spec.rb
@@ -3,7 +3,7 @@
 require "formula"
 require "software_spec"
 
-describe Bottle::Filename do
+RSpec.describe Bottle::Filename do
   subject { described_class.new(name, version, tag, rebuild) }
 
   let(:name) { "user/repo/foo" }
diff --git a/Library/Homebrew/test/build_environment_spec.rb b/Library/Homebrew/test/build_environment_spec.rb
index fa14acbe59..d2291371b1 100644
--- a/Library/Homebrew/test/build_environment_spec.rb
+++ b/Library/Homebrew/test/build_environment_spec.rb
@@ -2,7 +2,7 @@
 
 require "build_environment"
 
-describe BuildEnvironment do
+RSpec.describe BuildEnvironment do
   let(:env) { described_class.new }
 
   describe "#<<" do
diff --git a/Library/Homebrew/test/build_options_spec.rb b/Library/Homebrew/test/build_options_spec.rb
index cee085c83d..4ea4304504 100644
--- a/Library/Homebrew/test/build_options_spec.rb
+++ b/Library/Homebrew/test/build_options_spec.rb
@@ -3,7 +3,7 @@
 require "build_options"
 require "options"
 
-describe BuildOptions do
+RSpec.describe BuildOptions do
   alias_matcher :be_built_with, :be_with
   alias_matcher :be_built_without, :be_without
 
diff --git a/Library/Homebrew/test/bump_version_parser_spec.rb b/Library/Homebrew/test/bump_version_parser_spec.rb
index 3047ee6d9f..2e47b14868 100644
--- a/Library/Homebrew/test/bump_version_parser_spec.rb
+++ b/Library/Homebrew/test/bump_version_parser_spec.rb
@@ -2,7 +2,7 @@
 
 require "bump_version_parser"
 
-describe Homebrew::BumpVersionParser do
+RSpec.describe Homebrew::BumpVersionParser do
   let(:general_version) { "1.2.3" }
   let(:intel_version) { "2.3.4" }
   let(:arm_version) { "3.4.5" }
diff --git a/Library/Homebrew/test/bundle_version_spec.rb b/Library/Homebrew/test/bundle_version_spec.rb
index 7cec2e0bdf..646adb63aa 100644
--- a/Library/Homebrew/test/bundle_version_spec.rb
+++ b/Library/Homebrew/test/bundle_version_spec.rb
@@ -2,7 +2,7 @@
 
 require "bundle_version"
 
-describe Homebrew::BundleVersion do
+RSpec.describe Homebrew::BundleVersion do
   describe "#<=>" do
     it "compares both the `short_version` and `version`" do
       expect(described_class.new("1.2.3", "3000")).to be < described_class.new("1.2.3", "4000")
diff --git a/Library/Homebrew/test/cache_store_spec.rb b/Library/Homebrew/test/cache_store_spec.rb
index 242ae63d0f..cc950b83de 100644
--- a/Library/Homebrew/test/cache_store_spec.rb
+++ b/Library/Homebrew/test/cache_store_spec.rb
@@ -2,7 +2,7 @@
 
 require "cache_store"
 
-describe CacheStoreDatabase do
+RSpec.describe CacheStoreDatabase do
   subject(:sample_db) { described_class.new(:sample) }
 
   describe "self.use" do
diff --git a/Library/Homebrew/test/cask/artifact/abstract_artifact_spec.rb b/Library/Homebrew/test/cask/artifact/abstract_artifact_spec.rb
index 9de70da153..348011d80d 100644
--- a/Library/Homebrew/test/cask/artifact/abstract_artifact_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/abstract_artifact_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::AbstractArtifact, :cask do
+RSpec.describe Cask::Artifact::AbstractArtifact, :cask do
   describe ".read_script_arguments" do
     let(:stanza) { :installer }
 
diff --git a/Library/Homebrew/test/cask/artifact/alt_target_spec.rb b/Library/Homebrew/test/cask/artifact/alt_target_spec.rb
index b6d801e914..9bd396a9d4 100644
--- a/Library/Homebrew/test/cask/artifact/alt_target_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/alt_target_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::App, :cask do
+RSpec.describe Cask::Artifact::App, :cask do
   describe "activate to alternate target" do
     let(:cask) { Cask::CaskLoader.load(cask_path("with-alt-target")) }
 
diff --git a/Library/Homebrew/test/cask/artifact/app_spec.rb b/Library/Homebrew/test/cask/artifact/app_spec.rb
index 14f69a67ac..ccc0e3e1e0 100644
--- a/Library/Homebrew/test/cask/artifact/app_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/app_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::App, :cask do
+RSpec.describe Cask::Artifact::App, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("local-caffeine")) }
   let(:command) { NeverSudoSystemCommand }
   let(:adopt) { false }
diff --git a/Library/Homebrew/test/cask/artifact/binary_spec.rb b/Library/Homebrew/test/cask/artifact/binary_spec.rb
index 61436700ff..74afda456a 100644
--- a/Library/Homebrew/test/cask/artifact/binary_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/binary_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Binary, :cask do
+RSpec.describe Cask::Artifact::Binary, :cask do
   let(:cask) do
     Cask::CaskLoader.load(cask_path("with-binary")).tap do |cask|
       InstallHelper.install_without_artifacts(cask)
diff --git a/Library/Homebrew/test/cask/artifact/generic_artifact_spec.rb b/Library/Homebrew/test/cask/artifact/generic_artifact_spec.rb
index 8b65307acb..7359c29261 100644
--- a/Library/Homebrew/test/cask/artifact/generic_artifact_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/generic_artifact_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Artifact, :cask do
+RSpec.describe Cask::Artifact::Artifact, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("with-generic-artifact")) }
 
   let(:install_phase) do
diff --git a/Library/Homebrew/test/cask/artifact/installer_spec.rb b/Library/Homebrew/test/cask/artifact/installer_spec.rb
index d1f689555e..8730c5334b 100644
--- a/Library/Homebrew/test/cask/artifact/installer_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/installer_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Installer, :cask do
+RSpec.describe Cask::Artifact::Installer, :cask do
   subject(:installer) { described_class.new(cask, **args) }
 
   let(:staged_path) { mktmpdir }
diff --git a/Library/Homebrew/test/cask/artifact/manpage_spec.rb b/Library/Homebrew/test/cask/artifact/manpage_spec.rb
index 79f5f0741b..23048504e1 100644
--- a/Library/Homebrew/test/cask/artifact/manpage_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/manpage_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Manpage, :cask do
+RSpec.describe Cask::Artifact::Manpage, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_token) }
 
   context "without section" do
diff --git a/Library/Homebrew/test/cask/artifact/pkg_spec.rb b/Library/Homebrew/test/cask/artifact/pkg_spec.rb
index 6c015613b9..454e9eade4 100644
--- a/Library/Homebrew/test/cask/artifact/pkg_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/pkg_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Pkg, :cask do
+RSpec.describe Cask::Artifact::Pkg, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("with-installable")) }
   let(:fake_system_command) { class_double(SystemCommand) }
 
diff --git a/Library/Homebrew/test/cask/artifact/postflight_block_spec.rb b/Library/Homebrew/test/cask/artifact/postflight_block_spec.rb
index 6a070ba48a..b47d0cb052 100644
--- a/Library/Homebrew/test/cask/artifact/postflight_block_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/postflight_block_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::PostflightBlock, :cask do
+RSpec.describe Cask::Artifact::PostflightBlock, :cask do
   describe "install_phase" do
     it "calls the specified block after installing, passing a Cask mini-dsl" do
       called = false
diff --git a/Library/Homebrew/test/cask/artifact/preflight_block_spec.rb b/Library/Homebrew/test/cask/artifact/preflight_block_spec.rb
index f6832dde7f..923f40ac07 100644
--- a/Library/Homebrew/test/cask/artifact/preflight_block_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/preflight_block_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::PreflightBlock, :cask do
+RSpec.describe Cask::Artifact::PreflightBlock, :cask do
   describe "install_phase" do
     it "calls the specified block before installing, passing a Cask mini-dsl" do
       called = false
diff --git a/Library/Homebrew/test/cask/artifact/suite_spec.rb b/Library/Homebrew/test/cask/artifact/suite_spec.rb
index 009d790ed4..869508d454 100644
--- a/Library/Homebrew/test/cask/artifact/suite_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/suite_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Suite, :cask do
+RSpec.describe Cask::Artifact::Suite, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("with-suite")) }
 
   let(:install_phase) do
diff --git a/Library/Homebrew/test/cask/artifact/two_apps_correct_spec.rb b/Library/Homebrew/test/cask/artifact/two_apps_correct_spec.rb
index 53e2c4eccb..5a1e119bff 100644
--- a/Library/Homebrew/test/cask/artifact/two_apps_correct_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/two_apps_correct_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::App, :cask do
+RSpec.describe Cask::Artifact::App, :cask do
   describe "multiple apps" do
     let(:cask) { Cask::CaskLoader.load(cask_path("with-two-apps-correct")) }
 
diff --git a/Library/Homebrew/test/cask/artifact/uninstall_no_zap_spec.rb b/Library/Homebrew/test/cask/artifact/uninstall_no_zap_spec.rb
index 1328ed7de1..2a42e5a8d3 100644
--- a/Library/Homebrew/test/cask/artifact/uninstall_no_zap_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/uninstall_no_zap_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Artifact::Zap, :cask do
+RSpec.describe Cask::Artifact::Zap, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("with-installable")) }
 
   let(:zap_artifact) do
diff --git a/Library/Homebrew/test/cask/artifact/uninstall_spec.rb b/Library/Homebrew/test/cask/artifact/uninstall_spec.rb
index 5e4550fe97..d454b2de32 100644
--- a/Library/Homebrew/test/cask/artifact/uninstall_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/uninstall_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples/uninstall_zap"
 
-describe Cask::Artifact::Uninstall, :cask do
+RSpec.describe Cask::Artifact::Uninstall, :cask do
   describe "#uninstall_phase" do
     include_examples "#uninstall_phase or #zap_phase"
   end
diff --git a/Library/Homebrew/test/cask/artifact/zap_spec.rb b/Library/Homebrew/test/cask/artifact/zap_spec.rb
index c1ee2b0f59..3ae2f40d96 100644
--- a/Library/Homebrew/test/cask/artifact/zap_spec.rb
+++ b/Library/Homebrew/test/cask/artifact/zap_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples/uninstall_zap"
 
-describe Cask::Artifact::Zap, :cask do
+RSpec.describe Cask::Artifact::Zap, :cask do
   describe "#zap_phase" do
     include_examples "#uninstall_phase or #zap_phase"
 
diff --git a/Library/Homebrew/test/cask/audit_spec.rb b/Library/Homebrew/test/cask/audit_spec.rb
index 9d332e8f3c..c3102466f6 100644
--- a/Library/Homebrew/test/cask/audit_spec.rb
+++ b/Library/Homebrew/test/cask/audit_spec.rb
@@ -2,7 +2,7 @@
 
 require "cask/audit"
 
-describe Cask::Audit, :cask do
+RSpec.describe Cask::Audit, :cask do
   def include_msg?(problems, msg)
     if msg.is_a?(Regexp)
       Array(problems).any? { |problem| msg.match?(problem[:message]) }
diff --git a/Library/Homebrew/test/cask/cask_loader/from_api_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_api_loader_spec.rb
index a7ec38d858..7e567e95fe 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_api_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_api_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader::FromAPILoader, :cask do
+RSpec.describe Cask::CaskLoader::FromAPILoader, :cask do
   shared_context "with API setup" do |new_token|
     let(:token) { new_token }
     let(:cask_from_source) { Cask::CaskLoader.load(token) }
diff --git a/Library/Homebrew/test/cask/cask_loader/from_content_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_content_loader_spec.rb
index e4b5ce2efe..ca97c8b925 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_content_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_content_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader::FromContentLoader do
+RSpec.describe Cask::CaskLoader::FromContentLoader do
   describe "::try_new" do
     it "returns a loader for Casks specified with `cask \"token\" do … end`" do
       expect(described_class.try_new(<<~RUBY)).not_to be_nil
diff --git a/Library/Homebrew/test/cask/cask_loader/from_path_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_path_loader_spec.rb
index aceb017534..fccd5b580b 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_path_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_path_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader::FromPathLoader do
+RSpec.describe Cask::CaskLoader::FromPathLoader do
   describe "#load" do
     context "when the file does not contain a cask" do
       let(:path) do
diff --git a/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
index d352527261..f86a94c1d5 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader::FromTapLoader do
+RSpec.describe Cask::CaskLoader::FromTapLoader do
   let(:cask_name) { "testball" }
   let(:cask_full_name) { "homebrew/cask/#{cask_name}" }
   let(:cask_path) { CoreCaskTap.instance.cask_dir/"#{cask_name}.rb" }
diff --git a/Library/Homebrew/test/cask/cask_loader/from_uri_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_uri_loader_spec.rb
index fb838bac44..e4126b20b0 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_uri_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_uri_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader::FromURILoader do
+RSpec.describe Cask::CaskLoader::FromURILoader do
   describe "::try_new" do
     it "returns a loader when given an URI" do
       expect(described_class.try_new(URI("https://brew.sh/"))).not_to be_nil
diff --git a/Library/Homebrew/test/cask/cask_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader_spec.rb
index 42ed564eee..46228c6609 100644
--- a/Library/Homebrew/test/cask/cask_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::CaskLoader, :cask do
+RSpec.describe Cask::CaskLoader, :cask do
   describe "::for" do
     let(:tap) { CoreCaskTap.instance }
 
diff --git a/Library/Homebrew/test/cask/cask_spec.rb b/Library/Homebrew/test/cask/cask_spec.rb
index ebc393f7e6..4284294a0e 100644
--- a/Library/Homebrew/test/cask/cask_spec.rb
+++ b/Library/Homebrew/test/cask/cask_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Cask, :cask do
+RSpec.describe Cask::Cask, :cask do
   let(:cask) { described_class.new("versioned-cask") }
 
   context "when multiple versions are installed" do
diff --git a/Library/Homebrew/test/cask/config_spec.rb b/Library/Homebrew/test/cask/config_spec.rb
index 58a60a711a..bf7ba9b158 100644
--- a/Library/Homebrew/test/cask/config_spec.rb
+++ b/Library/Homebrew/test/cask/config_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Config, :cask do
+RSpec.describe Cask::Config, :cask do
   subject(:config) { described_class.new }
 
   describe "::from_json" do
diff --git a/Library/Homebrew/test/cask/conflicts_with_spec.rb b/Library/Homebrew/test/cask/conflicts_with_spec.rb
index fe3387003d..329a10e66a 100644
--- a/Library/Homebrew/test/cask/conflicts_with_spec.rb
+++ b/Library/Homebrew/test/cask/conflicts_with_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "conflicts_with", :cask do
+RSpec.describe "conflicts_with", :cask do
   describe "conflicts_with cask" do
     let(:local_caffeine) do
       Cask::CaskLoader.load(cask_path("local-caffeine"))
diff --git a/Library/Homebrew/test/cask/denylist_spec.rb b/Library/Homebrew/test/cask/denylist_spec.rb
index c4ad8e3bf6..69bef66e26 100644
--- a/Library/Homebrew/test/cask/denylist_spec.rb
+++ b/Library/Homebrew/test/cask/denylist_spec.rb
@@ -2,7 +2,7 @@
 
 require "cask/denylist"
 
-describe Cask::Denylist, :cask do
+RSpec.describe Cask::Denylist, :cask do
   describe "::reason" do
     matcher :disallow do |name|
       match do |expected|
diff --git a/Library/Homebrew/test/cask/depends_on_spec.rb b/Library/Homebrew/test/cask/depends_on_spec.rb
index 7d7eaa3429..dfb444abc5 100644
--- a/Library/Homebrew/test/cask/depends_on_spec.rb
+++ b/Library/Homebrew/test/cask/depends_on_spec.rb
@@ -2,7 +2,7 @@
 
 # TODO: this test should be named after the corresponding class, once
 #       that class is abstracted from installer.rb
-describe "Satisfy Dependencies and Requirements", :cask do
+RSpec.describe "Satisfy Dependencies and Requirements", :cask do
   subject(:install) do
     Cask::Installer.new(cask).install
   end
diff --git a/Library/Homebrew/test/cask/dsl/caveats_spec.rb b/Library/Homebrew/test/cask/dsl/caveats_spec.rb
index dd47a8a79d..762088517a 100644
--- a/Library/Homebrew/test/cask/dsl/caveats_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/caveats_spec.rb
@@ -2,7 +2,7 @@
 
 require "test/cask/dsl/shared_examples/base"
 
-describe Cask::DSL::Caveats, :cask do
+RSpec.describe Cask::DSL::Caveats, :cask do
   subject(:caveats) { described_class.new(cask) }
 
   let(:cask) { Cask::CaskLoader.load(cask_path("basic-cask")) }
diff --git a/Library/Homebrew/test/cask/dsl/container_spec.rb b/Library/Homebrew/test/cask/dsl/container_spec.rb
index 844cac897f..cd5e1c9713 100644
--- a/Library/Homebrew/test/cask/dsl/container_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/container_spec.rb
@@ -2,7 +2,7 @@
 
 require "test/cask/dsl/shared_examples/base"
 
-describe Cask::DSL::Container do
+RSpec.describe Cask::DSL::Container do
   subject(:container) { described_class.new(**params) }
 
   describe "#pairs" do
diff --git a/Library/Homebrew/test/cask/dsl/postflight_spec.rb b/Library/Homebrew/test/cask/dsl/postflight_spec.rb
index 30a18ca562..b8ba597746 100644
--- a/Library/Homebrew/test/cask/dsl/postflight_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/postflight_spec.rb
@@ -3,7 +3,7 @@
 require "test/cask/dsl/shared_examples/base"
 require "test/cask/dsl/shared_examples/staged"
 
-describe Cask::DSL::Postflight, :cask do
+RSpec.describe Cask::DSL::Postflight, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("basic-cask")) }
   let(:fake_system_command) { class_double(SystemCommand) }
   let(:dsl) { described_class.new(cask, fake_system_command) }
diff --git a/Library/Homebrew/test/cask/dsl/preflight_spec.rb b/Library/Homebrew/test/cask/dsl/preflight_spec.rb
index a229c91019..4ff7aa8559 100644
--- a/Library/Homebrew/test/cask/dsl/preflight_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/preflight_spec.rb
@@ -3,7 +3,7 @@
 require "test/cask/dsl/shared_examples/base"
 require "test/cask/dsl/shared_examples/staged"
 
-describe Cask::DSL::Preflight, :cask do
+RSpec.describe Cask::DSL::Preflight, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("basic-cask")) }
   let(:fake_system_command) { class_double(SystemCommand) }
   let(:dsl) { described_class.new(cask, fake_system_command) }
diff --git a/Library/Homebrew/test/cask/dsl/uninstall_postflight_spec.rb b/Library/Homebrew/test/cask/dsl/uninstall_postflight_spec.rb
index 60dabc7bcb..bcb0b135f6 100644
--- a/Library/Homebrew/test/cask/dsl/uninstall_postflight_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/uninstall_postflight_spec.rb
@@ -2,7 +2,7 @@
 
 require "test/cask/dsl/shared_examples/base"
 
-describe Cask::DSL::UninstallPostflight, :cask do
+RSpec.describe Cask::DSL::UninstallPostflight, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("basic-cask")) }
   let(:dsl) { described_class.new(cask, class_double(SystemCommand)) }
 
diff --git a/Library/Homebrew/test/cask/dsl/uninstall_preflight_spec.rb b/Library/Homebrew/test/cask/dsl/uninstall_preflight_spec.rb
index 97970f0e0e..9c7bec3aec 100644
--- a/Library/Homebrew/test/cask/dsl/uninstall_preflight_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/uninstall_preflight_spec.rb
@@ -3,7 +3,7 @@
 require "test/cask/dsl/shared_examples/base"
 require "test/cask/dsl/shared_examples/staged"
 
-describe Cask::DSL::UninstallPreflight, :cask do
+RSpec.describe Cask::DSL::UninstallPreflight, :cask do
   let(:cask) { Cask::CaskLoader.load(cask_path("basic-cask")) }
   let(:fake_system_command) { class_double(SystemCommand) }
   let(:dsl) { described_class.new(cask, fake_system_command) }
diff --git a/Library/Homebrew/test/cask/dsl/version_spec.rb b/Library/Homebrew/test/cask/dsl/version_spec.rb
index 68cf59d024..311329ce54 100644
--- a/Library/Homebrew/test/cask/dsl/version_spec.rb
+++ b/Library/Homebrew/test/cask/dsl/version_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::DSL::Version, :cask do
+RSpec.describe Cask::DSL::Version, :cask do
   shared_examples "expectations hash" do |input_name, expectations|
     expectations.each do |input_value, expected_output|
       context "when #{input_name} is #{input_value.inspect}" do
diff --git a/Library/Homebrew/test/cask/dsl_spec.rb b/Library/Homebrew/test/cask/dsl_spec.rb
index bfdd15d0e8..b7594c609a 100644
--- a/Library/Homebrew/test/cask/dsl_spec.rb
+++ b/Library/Homebrew/test/cask/dsl_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::DSL, :cask do
+RSpec.describe Cask::DSL, :cask do
   let(:cask) { Cask::CaskLoader.load(token) }
   let(:token) { "basic-cask" }
 
diff --git a/Library/Homebrew/test/cask/info_spec.rb b/Library/Homebrew/test/cask/info_spec.rb
index 697e6e918b..2c5a5aefc0 100644
--- a/Library/Homebrew/test/cask/info_spec.rb
+++ b/Library/Homebrew/test/cask/info_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils"
 
-describe Cask::Info, :cask do
+RSpec.describe Cask::Info, :cask do
   it "displays some nice info about the specified Cask" do
     expect do
       described_class.info(Cask::CaskLoader.load("local-transmission"))
diff --git a/Library/Homebrew/test/cask/installer_spec.rb b/Library/Homebrew/test/cask/installer_spec.rb
index 0555cf50ff..1bdfa80548 100644
--- a/Library/Homebrew/test/cask/installer_spec.rb
+++ b/Library/Homebrew/test/cask/installer_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Installer, :cask do
+RSpec.describe Cask::Installer, :cask do
   describe "install" do
     it "downloads and installs a nice fresh Cask" do
       caffeine = Cask::CaskLoader.load(cask_path("local-caffeine"))
diff --git a/Library/Homebrew/test/cask/list_spec.rb b/Library/Homebrew/test/cask/list_spec.rb
index 2b05119b3b..ff96c2cc26 100644
--- a/Library/Homebrew/test/cask/list_spec.rb
+++ b/Library/Homebrew/test/cask/list_spec.rb
@@ -2,7 +2,7 @@
 
 require "cask/list"
 
-describe Cask::List, :cask do
+RSpec.describe Cask::List, :cask do
   it "lists the installed Casks in a pretty fashion" do
     casks = %w[local-caffeine local-transmission].map { |c| Cask::CaskLoader.load(c) }
 
diff --git a/Library/Homebrew/test/cask/macos_spec.rb b/Library/Homebrew/test/cask/macos_spec.rb
index 2635e67f17..bb086d6501 100644
--- a/Library/Homebrew/test/cask/macos_spec.rb
+++ b/Library/Homebrew/test/cask/macos_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe MacOS, :cask do
+RSpec.describe MacOS, :cask do
   it "says '/' is undeletable" do
     expect(described_class).to be_undeletable(
       "/",
diff --git a/Library/Homebrew/test/cask/pkg_spec.rb b/Library/Homebrew/test/cask/pkg_spec.rb
index 314135e6a6..a0513c2053 100644
--- a/Library/Homebrew/test/cask/pkg_spec.rb
+++ b/Library/Homebrew/test/cask/pkg_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Pkg, :cask do
+RSpec.describe Cask::Pkg, :cask do
   describe "#uninstall" do
     let(:fake_system_command) { NeverSudoSystemCommand }
     let(:empty_response) do
diff --git a/Library/Homebrew/test/cask/reinstall_spec.rb b/Library/Homebrew/test/cask/reinstall_spec.rb
index 2ca6fff9d9..76d8346050 100644
--- a/Library/Homebrew/test/cask/reinstall_spec.rb
+++ b/Library/Homebrew/test/cask/reinstall_spec.rb
@@ -3,7 +3,7 @@
 require "cask/installer"
 require "cask/reinstall"
 
-describe Cask::Reinstall, :cask do
+RSpec.describe Cask::Reinstall, :cask do
   it "displays the reinstallation progress" do
     caffeine = Cask::CaskLoader.load(cask_path("local-caffeine"))
 
diff --git a/Library/Homebrew/test/cask/uninstall_spec.rb b/Library/Homebrew/test/cask/uninstall_spec.rb
index 61d0553e3d..e281a6a162 100644
--- a/Library/Homebrew/test/cask/uninstall_spec.rb
+++ b/Library/Homebrew/test/cask/uninstall_spec.rb
@@ -2,7 +2,7 @@
 
 require "cask/uninstall"
 
-describe Cask::Uninstall, :cask do
+RSpec.describe Cask::Uninstall, :cask do
   it "displays the uninstallation progress" do
     caffeine = Cask::CaskLoader.load(cask_path("local-caffeine"))
 
diff --git a/Library/Homebrew/test/cask/upgrade_spec.rb b/Library/Homebrew/test/cask/upgrade_spec.rb
index ad4d6f1644..940f547f5d 100644
--- a/Library/Homebrew/test/cask/upgrade_spec.rb
+++ b/Library/Homebrew/test/cask/upgrade_spec.rb
@@ -2,7 +2,7 @@
 
 require "cask/upgrade"
 
-describe Cask::Upgrade, :cask do
+RSpec.describe Cask::Upgrade, :cask do
   let(:version_latest_paths) do
     [
       version_latest.config.appdir.join("Caffeine Mini.app"),
diff --git a/Library/Homebrew/test/cask/utils_spec.rb b/Library/Homebrew/test/cask/utils_spec.rb
index 634afaeb95..394879957d 100644
--- a/Library/Homebrew/test/cask/utils_spec.rb
+++ b/Library/Homebrew/test/cask/utils_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Cask::Utils do
+RSpec.describe Cask::Utils do
   let(:command) { NeverSudoSystemCommand }
   let(:dir) { mktmpdir }
   let(:path) { dir/"a/b/c" }
diff --git a/Library/Homebrew/test/cask_dependent_spec.rb b/Library/Homebrew/test/cask_dependent_spec.rb
index 1d54b8064d..48e09d16fe 100644
--- a/Library/Homebrew/test/cask_dependent_spec.rb
+++ b/Library/Homebrew/test/cask_dependent_spec.rb
@@ -3,7 +3,7 @@
 require "cask/cask_loader"
 require "cask_dependent"
 
-describe CaskDependent, :needs_macos do
+RSpec.describe CaskDependent, :needs_macos do
   subject(:dependent) { described_class.new test_cask }
 
   let :test_cask do
diff --git a/Library/Homebrew/test/caveats_spec.rb b/Library/Homebrew/test/caveats_spec.rb
index 3a8ce307db..58b41f24f9 100644
--- a/Library/Homebrew/test/caveats_spec.rb
+++ b/Library/Homebrew/test/caveats_spec.rb
@@ -3,7 +3,7 @@
 require "formula"
 require "caveats"
 
-describe Caveats do
+RSpec.describe Caveats do
   subject(:caveats) { described_class.new(f) }
 
   let(:f) { formula { url "foo-1.0" } }
diff --git a/Library/Homebrew/test/checksum_spec.rb b/Library/Homebrew/test/checksum_spec.rb
index be60737e4d..e1b7e28c17 100644
--- a/Library/Homebrew/test/checksum_spec.rb
+++ b/Library/Homebrew/test/checksum_spec.rb
@@ -2,7 +2,7 @@
 
 require "checksum"
 
-describe Checksum do
+RSpec.describe Checksum do
   describe "#empty?" do
     subject { described_class.new("") }
 
diff --git a/Library/Homebrew/test/checksum_verification_spec.rb b/Library/Homebrew/test/checksum_verification_spec.rb
index f0420adac9..3664e419a1 100644
--- a/Library/Homebrew/test/checksum_verification_spec.rb
+++ b/Library/Homebrew/test/checksum_verification_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   def formula(&block)
     super do
       url "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz"
diff --git a/Library/Homebrew/test/cleaner_spec.rb b/Library/Homebrew/test/cleaner_spec.rb
index b7ba8082de..0c02b81256 100644
--- a/Library/Homebrew/test/cleaner_spec.rb
+++ b/Library/Homebrew/test/cleaner_spec.rb
@@ -3,7 +3,7 @@
 require "cleaner"
 require "formula"
 
-describe Cleaner do
+RSpec.describe Cleaner do
   include FileUtils
 
   describe "#clean" do
diff --git a/Library/Homebrew/test/cleanup_spec.rb b/Library/Homebrew/test/cleanup_spec.rb
index 80d19625ca..b4a09a8721 100644
--- a/Library/Homebrew/test/cleanup_spec.rb
+++ b/Library/Homebrew/test/cleanup_spec.rb
@@ -5,7 +5,7 @@ require "cleanup"
 require "cask/cache"
 require "fileutils"
 
-describe Homebrew::Cleanup do
+RSpec.describe Homebrew::Cleanup do
   subject(:cleanup) { described_class.new }
 
   let(:ds_store) { Pathname.new("#{HOMEBREW_CELLAR}/.DS_Store") }
diff --git a/Library/Homebrew/test/cli/named_args_spec.rb b/Library/Homebrew/test/cli/named_args_spec.rb
index dc04310dff..b1f5c115cc 100644
--- a/Library/Homebrew/test/cli/named_args_spec.rb
+++ b/Library/Homebrew/test/cli/named_args_spec.rb
@@ -2,7 +2,7 @@
 
 require "cli/named_args"
 
-describe Homebrew::CLI::NamedArgs do
+RSpec.describe Homebrew::CLI::NamedArgs do
   def setup_unredable_formula(name)
     error = FormulaUnreadableError.new(name, RuntimeError.new("testing"))
     allow(Formulary).to receive(:factory).with(name, any_args).and_raise(error)
diff --git a/Library/Homebrew/test/cli/parser_spec.rb b/Library/Homebrew/test/cli/parser_spec.rb
index 68ab766fcb..5232fc4673 100644
--- a/Library/Homebrew/test/cli/parser_spec.rb
+++ b/Library/Homebrew/test/cli/parser_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "../../cli/parser"
 
-describe Homebrew::CLI::Parser do
+RSpec.describe Homebrew::CLI::Parser do
   describe "test switch options" do
     subject(:parser) do
       described_class.new do
diff --git a/Library/Homebrew/test/cmd/--cache_spec.rb b/Library/Homebrew/test/cmd/--cache_spec.rb
index cb371b577a..06eed15583 100644
--- a/Library/Homebrew/test/cmd/--cache_spec.rb
+++ b/Library/Homebrew/test/cmd/--cache_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --cache" do
+RSpec.describe "brew --cache" do
   it_behaves_like "parseable arguments"
 
   it "prints all cache files for a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--caskroom_spec.rb b/Library/Homebrew/test/cmd/--caskroom_spec.rb
index bd8ec0fbd0..58e7ac4e95 100644
--- a/Library/Homebrew/test/cmd/--caskroom_spec.rb
+++ b/Library/Homebrew/test/cmd/--caskroom_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --caskroom" do
+RSpec.describe "brew --caskroom" do
   it_behaves_like "parseable arguments"
 
   it "prints Homebrew's Caskroom", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--cellar_spec.rb b/Library/Homebrew/test/cmd/--cellar_spec.rb
index d57bb89ed4..45bcc8dfa3 100644
--- a/Library/Homebrew/test/cmd/--cellar_spec.rb
+++ b/Library/Homebrew/test/cmd/--cellar_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --cellar" do
+RSpec.describe "brew --cellar" do
   it_behaves_like "parseable arguments"
 
   it "prints Homebrew's Cellar", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--env_spec.rb b/Library/Homebrew/test/cmd/--env_spec.rb
index a0a848dd11..dcddb15fd2 100644
--- a/Library/Homebrew/test/cmd/--env_spec.rb
+++ b/Library/Homebrew/test/cmd/--env_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --env" do
+RSpec.describe "brew --env" do
   it_behaves_like "parseable arguments"
 
   describe "--shell=bash", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--prefix_spec.rb b/Library/Homebrew/test/cmd/--prefix_spec.rb
index b55826b2d3..9062f767cc 100644
--- a/Library/Homebrew/test/cmd/--prefix_spec.rb
+++ b/Library/Homebrew/test/cmd/--prefix_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --prefix" do
+RSpec.describe "brew --prefix" do
   it_behaves_like "parseable arguments"
 
   it "prints Homebrew's prefix", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--repository_spec.rb b/Library/Homebrew/test/cmd/--repository_spec.rb
index c435414e81..c56ef7b52e 100644
--- a/Library/Homebrew/test/cmd/--repository_spec.rb
+++ b/Library/Homebrew/test/cmd/--repository_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --repository" do
+RSpec.describe "brew --repository" do
   it_behaves_like "parseable arguments"
 
   it "prints Homebrew's repository", :integration_test do
diff --git a/Library/Homebrew/test/cmd/--version_spec.rb b/Library/Homebrew/test/cmd/--version_spec.rb
index 94f99b3bf9..75cf483a52 100644
--- a/Library/Homebrew/test/cmd/--version_spec.rb
+++ b/Library/Homebrew/test/cmd/--version_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew --version" do
+RSpec.describe "brew --version" do
   it "prints the Homebrew's version", :integration_test do
     expect { brew_sh "--version" }
       .to output(/^Homebrew #{Regexp.escape(HOMEBREW_VERSION)}\n/o).to_stdout
diff --git a/Library/Homebrew/test/cmd/analytics_spec.rb b/Library/Homebrew/test/cmd/analytics_spec.rb
index 7170c78fc3..c0cc6c75a2 100644
--- a/Library/Homebrew/test/cmd/analytics_spec.rb
+++ b/Library/Homebrew/test/cmd/analytics_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew analytics" do
+RSpec.describe "brew analytics" do
   it_behaves_like "parseable arguments"
 
   it "when HOMEBREW_NO_ANALYTICS is unset is disabled after running `brew analytics off`", :integration_test do
diff --git a/Library/Homebrew/test/cmd/autoremove_spec.rb b/Library/Homebrew/test/cmd/autoremove_spec.rb
index 84f9eb8970..86aea1e75c 100644
--- a/Library/Homebrew/test/cmd/autoremove_spec.rb
+++ b/Library/Homebrew/test/cmd/autoremove_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew autoremove" do
+RSpec.describe "brew autoremove" do
   it_behaves_like "parseable arguments"
 
   describe "integration test" do
diff --git a/Library/Homebrew/test/cmd/bundle_spec.rb b/Library/Homebrew/test/cmd/bundle_spec.rb
index 63bb8f509f..4a1b4c9255 100644
--- a/Library/Homebrew/test/cmd/bundle_spec.rb
+++ b/Library/Homebrew/test/cmd/bundle_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew bundle", :integration_test do
+RSpec.describe "brew bundle", :integration_test do
   describe "check" do
     it "checks if a Brewfile's dependencies are satisfied", :needs_network do
       setup_remote_tap "homebrew/bundle"
diff --git a/Library/Homebrew/test/cmd/cleanup_spec.rb b/Library/Homebrew/test/cmd/cleanup_spec.rb
index 38068c41df..170668f417 100644
--- a/Library/Homebrew/test/cmd/cleanup_spec.rb
+++ b/Library/Homebrew/test/cmd/cleanup_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew cleanup" do
+RSpec.describe "brew cleanup" do
   before do
     FileUtils.mkdir_p HOMEBREW_LIBRARY/"Homebrew/vendor/"
     FileUtils.touch HOMEBREW_LIBRARY/"Homebrew/vendor/portable-ruby-version"
diff --git a/Library/Homebrew/test/cmd/commands_spec.rb b/Library/Homebrew/test/cmd/commands_spec.rb
index 4a63056f8d..b49068378d 100644
--- a/Library/Homebrew/test/cmd/commands_spec.rb
+++ b/Library/Homebrew/test/cmd/commands_spec.rb
@@ -5,7 +5,7 @@ require "fileutils"
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew commands" do
+RSpec.describe "brew commands" do
   it_behaves_like "parseable arguments"
 
   it "prints a list of all available commands", :integration_test do
diff --git a/Library/Homebrew/test/cmd/completions_spec.rb b/Library/Homebrew/test/cmd/completions_spec.rb
index a92a73df4c..ab0bd90a63 100644
--- a/Library/Homebrew/test/cmd/completions_spec.rb
+++ b/Library/Homebrew/test/cmd/completions_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew completions" do
+RSpec.describe "brew completions" do
   it_behaves_like "parseable arguments"
 
   it "runs the status subcommand correctly", :integration_test do
diff --git a/Library/Homebrew/test/cmd/config_spec.rb b/Library/Homebrew/test/cmd/config_spec.rb
index 946e6ac841..d5621f4541 100644
--- a/Library/Homebrew/test/cmd/config_spec.rb
+++ b/Library/Homebrew/test/cmd/config_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew config" do
+RSpec.describe "brew config" do
   it_behaves_like "parseable arguments"
 
   it "prints information about the current Homebrew configuration", :integration_test do
diff --git a/Library/Homebrew/test/cmd/custom-external-command_spec.rb b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
index 31d90752fd..d16bb4ad54 100644
--- a/Library/Homebrew/test/cmd/custom-external-command_spec.rb
+++ b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew custom-external-command", :integration_test do
+RSpec.describe "brew custom-external-command", :integration_test do
   it "is supported" do
     mktmpdir do |path|
       cmd = "custom-external-command-#{rand}"
diff --git a/Library/Homebrew/test/cmd/deps_spec.rb b/Library/Homebrew/test/cmd/deps_spec.rb
index 4676d06587..aa6277196b 100644
--- a/Library/Homebrew/test/cmd/deps_spec.rb
+++ b/Library/Homebrew/test/cmd/deps_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew deps" do
+RSpec.describe "brew deps" do
   it_behaves_like "parseable arguments"
 
   it "outputs all of a Formula's dependencies and their dependencies on separate lines", :integration_test do
diff --git a/Library/Homebrew/test/cmd/desc_spec.rb b/Library/Homebrew/test/cmd/desc_spec.rb
index f21ece3877..28872ed0c9 100644
--- a/Library/Homebrew/test/cmd/desc_spec.rb
+++ b/Library/Homebrew/test/cmd/desc_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew desc" do
+RSpec.describe "brew desc" do
   it_behaves_like "parseable arguments"
 
   it "shows a given Formula's description", :integration_test do
diff --git a/Library/Homebrew/test/cmd/developer_spec.rb b/Library/Homebrew/test/cmd/developer_spec.rb
index cfc2f24a9f..1b6bc17622 100644
--- a/Library/Homebrew/test/cmd/developer_spec.rb
+++ b/Library/Homebrew/test/cmd/developer_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew developer" do
+RSpec.describe "brew developer" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/cmd/docs_spec.rb b/Library/Homebrew/test/cmd/docs_spec.rb
index 72488b5619..5379c21717 100644
--- a/Library/Homebrew/test/cmd/docs_spec.rb
+++ b/Library/Homebrew/test/cmd/docs_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew docs" do
+RSpec.describe "brew docs" do
   it "opens the docs page", :integration_test do
     expect { brew "docs", "HOMEBREW_BROWSER" => "echo" }
       .to output("https://docs.brew.sh\n").to_stdout
diff --git a/Library/Homebrew/test/cmd/doctor_spec.rb b/Library/Homebrew/test/cmd/doctor_spec.rb
index 8cb1add72d..c82dfb3458 100644
--- a/Library/Homebrew/test/cmd/doctor_spec.rb
+++ b/Library/Homebrew/test/cmd/doctor_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew doctor" do
+RSpec.describe "brew doctor" do
   it_behaves_like "parseable arguments"
 
   specify "check_integration_test", :integration_test do
diff --git a/Library/Homebrew/test/cmd/fetch_spec.rb b/Library/Homebrew/test/cmd/fetch_spec.rb
index 08e58c4864..96c07722d9 100644
--- a/Library/Homebrew/test/cmd/fetch_spec.rb
+++ b/Library/Homebrew/test/cmd/fetch_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew fetch" do
+RSpec.describe "brew fetch" do
   it_behaves_like "parseable arguments"
 
   it "downloads the Formula's URL", :integration_test do
diff --git a/Library/Homebrew/test/cmd/gist-logs_spec.rb b/Library/Homebrew/test/cmd/gist-logs_spec.rb
index c6965e4a6d..25bb9ff393 100644
--- a/Library/Homebrew/test/cmd/gist-logs_spec.rb
+++ b/Library/Homebrew/test/cmd/gist-logs_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew gist-logs" do
+RSpec.describe "brew gist-logs" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/cmd/help_spec.rb b/Library/Homebrew/test/cmd/help_spec.rb
index 0166969dc9..ff82501f5a 100644
--- a/Library/Homebrew/test/cmd/help_spec.rb
+++ b/Library/Homebrew/test/cmd/help_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew", :integration_test do
+RSpec.describe "brew", :integration_test do
   describe "help" do
     it "prints help for a documented Ruby command" do
       expect { brew "help", "cat" }
diff --git a/Library/Homebrew/test/cmd/home_spec.rb b/Library/Homebrew/test/cmd/home_spec.rb
index a622f9d2b3..65886736bd 100644
--- a/Library/Homebrew/test/cmd/home_spec.rb
+++ b/Library/Homebrew/test/cmd/home_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew home" do
+RSpec.describe "brew home" do
   let(:testballhome_homepage) do
     Formula["testballhome"].homepage
   end
diff --git a/Library/Homebrew/test/cmd/info_spec.rb b/Library/Homebrew/test/cmd/info_spec.rb
index 94911348fe..de636a6e4e 100644
--- a/Library/Homebrew/test/cmd/info_spec.rb
+++ b/Library/Homebrew/test/cmd/info_spec.rb
@@ -4,7 +4,7 @@ require "cmd/info"
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew info" do
+RSpec.describe "brew info" do
   it_behaves_like "parseable arguments"
 
   it "prints as json with the --json=v1 flag", :integration_test do
diff --git a/Library/Homebrew/test/cmd/install_spec.rb b/Library/Homebrew/test/cmd/install_spec.rb
index 2cf96730dc..c78c737f50 100644
--- a/Library/Homebrew/test/cmd/install_spec.rb
+++ b/Library/Homebrew/test/cmd/install_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew install" do
+RSpec.describe "brew install" do
   it_behaves_like "parseable arguments"
 
   it "installs formulae", :integration_test do
diff --git a/Library/Homebrew/test/cmd/leaves_spec.rb b/Library/Homebrew/test/cmd/leaves_spec.rb
index 49fc18d045..2b6fc51bee 100644
--- a/Library/Homebrew/test/cmd/leaves_spec.rb
+++ b/Library/Homebrew/test/cmd/leaves_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew leaves" do
+RSpec.describe "brew leaves" do
   it_behaves_like "parseable arguments"
 
   context "when there are no installed Formulae", :integration_test do
diff --git a/Library/Homebrew/test/cmd/link_spec.rb b/Library/Homebrew/test/cmd/link_spec.rb
index 79c527059e..ea0f99411c 100644
--- a/Library/Homebrew/test/cmd/link_spec.rb
+++ b/Library/Homebrew/test/cmd/link_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew link" do
+RSpec.describe "brew link" do
   it_behaves_like "parseable arguments"
 
   it "links a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/list_spec.rb b/Library/Homebrew/test/cmd/list_spec.rb
index 771db61f0d..414862251c 100644
--- a/Library/Homebrew/test/cmd/list_spec.rb
+++ b/Library/Homebrew/test/cmd/list_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew list" do
+RSpec.describe "brew list" do
   let(:formulae) { %w[bar foo qux] }
 
   it_behaves_like "parseable arguments"
diff --git a/Library/Homebrew/test/cmd/log_spec.rb b/Library/Homebrew/test/cmd/log_spec.rb
index 164df47cb7..9ac40c7856 100644
--- a/Library/Homebrew/test/cmd/log_spec.rb
+++ b/Library/Homebrew/test/cmd/log_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew log" do
+RSpec.describe "brew log" do
   it_behaves_like "parseable arguments"
 
   it "shows the Git log for a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/migrate_spec.rb b/Library/Homebrew/test/cmd/migrate_spec.rb
index d516ebf2f4..3292d247b3 100644
--- a/Library/Homebrew/test/cmd/migrate_spec.rb
+++ b/Library/Homebrew/test/cmd/migrate_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew migrate" do
+RSpec.describe "brew migrate" do
   it_behaves_like "parseable arguments"
 
   it "migrates a renamed Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/missing_spec.rb b/Library/Homebrew/test/cmd/missing_spec.rb
index e245d9b5ba..0e9043bdce 100644
--- a/Library/Homebrew/test/cmd/missing_spec.rb
+++ b/Library/Homebrew/test/cmd/missing_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew missing" do
+RSpec.describe "brew missing" do
   it_behaves_like "parseable arguments"
 
   it "prints missing dependencies", :integration_test do
diff --git a/Library/Homebrew/test/cmd/options_spec.rb b/Library/Homebrew/test/cmd/options_spec.rb
index f35b9c5a23..b7498aed15 100644
--- a/Library/Homebrew/test/cmd/options_spec.rb
+++ b/Library/Homebrew/test/cmd/options_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew options" do
+RSpec.describe "brew options" do
   it_behaves_like "parseable arguments"
 
   it "prints a given Formula's options", :integration_test do
diff --git a/Library/Homebrew/test/cmd/outdated_spec.rb b/Library/Homebrew/test/cmd/outdated_spec.rb
index bc52f6a4d9..ec402375a2 100644
--- a/Library/Homebrew/test/cmd/outdated_spec.rb
+++ b/Library/Homebrew/test/cmd/outdated_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew outdated" do
+RSpec.describe "brew outdated" do
   it_behaves_like "parseable arguments"
 
   it "outputs JSON", :integration_test do
diff --git a/Library/Homebrew/test/cmd/pin_spec.rb b/Library/Homebrew/test/cmd/pin_spec.rb
index c7ca4eb6b1..95fe1180e7 100644
--- a/Library/Homebrew/test/cmd/pin_spec.rb
+++ b/Library/Homebrew/test/cmd/pin_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew pin" do
+RSpec.describe "brew pin" do
   it_behaves_like "parseable arguments"
 
   it "pins a Formula's version", :integration_test do
diff --git a/Library/Homebrew/test/cmd/postinstall_spec.rb b/Library/Homebrew/test/cmd/postinstall_spec.rb
index 827d0bd9d6..30a7911c22 100644
--- a/Library/Homebrew/test/cmd/postinstall_spec.rb
+++ b/Library/Homebrew/test/cmd/postinstall_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew postinstall" do
+RSpec.describe "brew postinstall" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/cmd/readall_spec.rb b/Library/Homebrew/test/cmd/readall_spec.rb
index 19c6727dd1..3714d79f26 100644
--- a/Library/Homebrew/test/cmd/readall_spec.rb
+++ b/Library/Homebrew/test/cmd/readall_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew readall" do
+RSpec.describe "brew readall" do
   it_behaves_like "parseable arguments"
 
   it "imports all Formulae for a given Tap", :integration_test do
diff --git a/Library/Homebrew/test/cmd/reinstall_spec.rb b/Library/Homebrew/test/cmd/reinstall_spec.rb
index cd63a8cba1..7f86c175fa 100644
--- a/Library/Homebrew/test/cmd/reinstall_spec.rb
+++ b/Library/Homebrew/test/cmd/reinstall_spec.rb
@@ -3,7 +3,7 @@
 require "extend/ENV"
 require "cmd/shared_examples/args_parse"
 
-describe "brew reinstall" do
+RSpec.describe "brew reinstall" do
   it_behaves_like "parseable arguments"
 
   it "reinstalls a Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/search_spec.rb b/Library/Homebrew/test/cmd/search_spec.rb
index c3d8bee8aa..6d14ba8158 100644
--- a/Library/Homebrew/test/cmd/search_spec.rb
+++ b/Library/Homebrew/test/cmd/search_spec.rb
@@ -3,7 +3,7 @@
 require "cmd/search"
 require "cmd/shared_examples/args_parse"
 
-describe "brew search" do
+RSpec.describe "brew search" do
   it_behaves_like "parseable arguments"
 
   it "finds formula in search", :integration_test do
diff --git a/Library/Homebrew/test/cmd/services_spec.rb b/Library/Homebrew/test/cmd/services_spec.rb
index 81f2ef0a84..2324377aa3 100644
--- a/Library/Homebrew/test/cmd/services_spec.rb
+++ b/Library/Homebrew/test/cmd/services_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew services", :integration_test, :needs_network do
+RSpec.describe "brew services", :integration_test, :needs_network do
   it "allows controlling services" do
     setup_remote_tap "homebrew/services"
 
diff --git a/Library/Homebrew/test/cmd/tap-info_spec.rb b/Library/Homebrew/test/cmd/tap-info_spec.rb
index 144c7d4c36..b67f31cb00 100644
--- a/Library/Homebrew/test/cmd/tap-info_spec.rb
+++ b/Library/Homebrew/test/cmd/tap-info_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew tap-info" do
+RSpec.describe "brew tap-info" do
   it_behaves_like "parseable arguments"
 
   it "gets information for a given Tap", :integration_test, :needs_network do
diff --git a/Library/Homebrew/test/cmd/tap_spec.rb b/Library/Homebrew/test/cmd/tap_spec.rb
index 42137d1995..36d018eeab 100644
--- a/Library/Homebrew/test/cmd/tap_spec.rb
+++ b/Library/Homebrew/test/cmd/tap_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew tap" do
+RSpec.describe "brew tap" do
   it_behaves_like "parseable arguments"
 
   it "taps a given Tap", :integration_test do
diff --git a/Library/Homebrew/test/cmd/uninstall_spec.rb b/Library/Homebrew/test/cmd/uninstall_spec.rb
index 89aef3b423..f4ee92782a 100644
--- a/Library/Homebrew/test/cmd/uninstall_spec.rb
+++ b/Library/Homebrew/test/cmd/uninstall_spec.rb
@@ -4,7 +4,7 @@ require "cmd/uninstall"
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew uninstall" do
+RSpec.describe "brew uninstall" do
   it_behaves_like "parseable arguments"
 
   it "uninstalls a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/unlink_spec.rb b/Library/Homebrew/test/cmd/unlink_spec.rb
index 40c389d7c8..36f0e08337 100644
--- a/Library/Homebrew/test/cmd/unlink_spec.rb
+++ b/Library/Homebrew/test/cmd/unlink_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew unlink" do
+RSpec.describe "brew unlink" do
   it_behaves_like "parseable arguments"
 
   it "unlinks a Formula", :integration_test do
diff --git a/Library/Homebrew/test/cmd/unpin_spec.rb b/Library/Homebrew/test/cmd/unpin_spec.rb
index 6750104369..a3ba1df7b2 100644
--- a/Library/Homebrew/test/cmd/unpin_spec.rb
+++ b/Library/Homebrew/test/cmd/unpin_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew unpin" do
+RSpec.describe "brew unpin" do
   it_behaves_like "parseable arguments"
 
   it "unpins a Formula's version", :integration_test do
diff --git a/Library/Homebrew/test/cmd/untap_spec.rb b/Library/Homebrew/test/cmd/untap_spec.rb
index abf6b17484..d7e13fffd4 100644
--- a/Library/Homebrew/test/cmd/untap_spec.rb
+++ b/Library/Homebrew/test/cmd/untap_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew untap" do
+RSpec.describe "brew untap" do
   it_behaves_like "parseable arguments"
 
   it "untaps a given Tap", :integration_test do
diff --git a/Library/Homebrew/test/cmd/update-report_spec.rb b/Library/Homebrew/test/cmd/update-report_spec.rb
index 081cebdc57..4a3037ee57 100644
--- a/Library/Homebrew/test/cmd/update-report_spec.rb
+++ b/Library/Homebrew/test/cmd/update-report_spec.rb
@@ -5,7 +5,7 @@ require "formula_versions"
 require "yaml"
 require "cmd/shared_examples/args_parse"
 
-describe "brew update-report" do
+RSpec.describe "brew update-report" do
   it_behaves_like "parseable arguments"
 
   describe Reporter do
diff --git a/Library/Homebrew/test/cmd/upgrade_spec.rb b/Library/Homebrew/test/cmd/upgrade_spec.rb
index 9711e41804..6da0f140ce 100644
--- a/Library/Homebrew/test/cmd/upgrade_spec.rb
+++ b/Library/Homebrew/test/cmd/upgrade_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew upgrade" do
+RSpec.describe "brew upgrade" do
   it_behaves_like "parseable arguments"
 
   it "upgrades a Formula and cleans up old versions", :integration_test do
diff --git a/Library/Homebrew/test/cmd/uses_spec.rb b/Library/Homebrew/test/cmd/uses_spec.rb
index eef1cc603a..3495adca0a 100644
--- a/Library/Homebrew/test/cmd/uses_spec.rb
+++ b/Library/Homebrew/test/cmd/uses_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew uses" do
+RSpec.describe "brew uses" do
   it_behaves_like "parseable arguments"
 
   it "prints the Formulae a given Formula is used by", :integration_test do
diff --git a/Library/Homebrew/test/commands_spec.rb b/Library/Homebrew/test/commands_spec.rb
index f055485071..cb1a50306e 100644
--- a/Library/Homebrew/test/commands_spec.rb
+++ b/Library/Homebrew/test/commands_spec.rb
@@ -26,7 +26,7 @@ RSpec.shared_context "custom internal commands" do # rubocop:disable RSpec/Conte
   end
 end
 
-describe Commands do
+RSpec.describe Commands do
   include_context "custom internal commands"
 
   specify "::internal_commands" do
diff --git a/Library/Homebrew/test/compiler_failure_spec.rb b/Library/Homebrew/test/compiler_failure_spec.rb
index ab214e20f2..a30870c4f9 100644
--- a/Library/Homebrew/test/compiler_failure_spec.rb
+++ b/Library/Homebrew/test/compiler_failure_spec.rb
@@ -2,7 +2,7 @@
 
 require "compilers"
 
-describe CompilerFailure do
+RSpec.describe CompilerFailure do
   alias_matcher :fail_with, :be_fails_with
 
   describe "::create" do
diff --git a/Library/Homebrew/test/compiler_selector_spec.rb b/Library/Homebrew/test/compiler_selector_spec.rb
index 43f4fb5f04..c0d0731358 100644
--- a/Library/Homebrew/test/compiler_selector_spec.rb
+++ b/Library/Homebrew/test/compiler_selector_spec.rb
@@ -3,7 +3,7 @@
 require "compilers"
 require "software_spec"
 
-describe CompilerSelector do
+RSpec.describe CompilerSelector do
   subject(:selector) { described_class.new(software_spec, versions, compilers) }
 
   let(:compilers) { [:clang, :gnu] }
diff --git a/Library/Homebrew/test/completions_spec.rb b/Library/Homebrew/test/completions_spec.rb
index 9d166d95a4..0ad090c8d7 100644
--- a/Library/Homebrew/test/completions_spec.rb
+++ b/Library/Homebrew/test/completions_spec.rb
@@ -2,7 +2,7 @@
 
 require "completions"
 
-describe Homebrew::Completions do
+RSpec.describe Homebrew::Completions do
   let(:completions_dir) { HOMEBREW_REPOSITORY/"completions" }
   let(:internal_path) { HOMEBREW_REPOSITORY/"Library/Taps/homebrew/homebrew-bar" }
   let(:external_path) { HOMEBREW_REPOSITORY/"Library/Taps/foo/homebrew-bar" }
diff --git a/Library/Homebrew/test/cxxstdlib_spec.rb b/Library/Homebrew/test/cxxstdlib_spec.rb
index b9f3c56dcc..b5bb1e780c 100644
--- a/Library/Homebrew/test/cxxstdlib_spec.rb
+++ b/Library/Homebrew/test/cxxstdlib_spec.rb
@@ -3,7 +3,7 @@
 require "formula"
 require "cxxstdlib"
 
-describe CxxStdlib do
+RSpec.describe CxxStdlib do
   let(:clang) { described_class.create(:libstdcxx, :clang) }
   let(:lcxx) { described_class.create(:libcxx, :clang) }
 
diff --git a/Library/Homebrew/test/dependable_spec.rb b/Library/Homebrew/test/dependable_spec.rb
index 6f8ff901af..f9f38d078c 100644
--- a/Library/Homebrew/test/dependable_spec.rb
+++ b/Library/Homebrew/test/dependable_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependable"
 
-describe Dependable do
+RSpec.describe Dependable do
   alias_matcher :be_a_build_dependency, :be_build
 
   subject(:dependable) do
diff --git a/Library/Homebrew/test/dependencies_helpers_spec.rb b/Library/Homebrew/test/dependencies_helpers_spec.rb
index 4686084bce..bae4998fe1 100644
--- a/Library/Homebrew/test/dependencies_helpers_spec.rb
+++ b/Library/Homebrew/test/dependencies_helpers_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependencies_helpers"
 
-describe DependenciesHelpers do
+RSpec.describe DependenciesHelpers do
   specify "#dependents" do
     foo = formula "foo" do
       url "foo"
diff --git a/Library/Homebrew/test/dependencies_spec.rb b/Library/Homebrew/test/dependencies_spec.rb
index 3ea90f6482..6f2c2e80a4 100644
--- a/Library/Homebrew/test/dependencies_spec.rb
+++ b/Library/Homebrew/test/dependencies_spec.rb
@@ -3,7 +3,7 @@
 require "dependencies"
 require "dependency"
 
-describe Dependencies do
+RSpec.describe Dependencies do
   subject(:dependencies) { described_class.new }
 
   describe "#<<" do
diff --git a/Library/Homebrew/test/dependency_collector_spec.rb b/Library/Homebrew/test/dependency_collector_spec.rb
index 1af0d4f05f..5d7b84906d 100644
--- a/Library/Homebrew/test/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/dependency_collector_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependency_collector"
 
-describe DependencyCollector do
+RSpec.describe DependencyCollector do
   alias_matcher :be_a_build_requirement, :be_build
 
   subject(:collector) { described_class.new }
diff --git a/Library/Homebrew/test/dependency_expansion_spec.rb b/Library/Homebrew/test/dependency_expansion_spec.rb
index 960e78b7d6..c02332a1d9 100644
--- a/Library/Homebrew/test/dependency_expansion_spec.rb
+++ b/Library/Homebrew/test/dependency_expansion_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependency"
 
-describe Dependency do
+RSpec.describe Dependency do
   def build_dep(name, tags = [], deps = [])
     dep = described_class.new(name.to_s, tags)
     allow(dep).to receive(:to_formula).and_return \
diff --git a/Library/Homebrew/test/dependency_spec.rb b/Library/Homebrew/test/dependency_spec.rb
index f38530d92b..cd84d51edb 100644
--- a/Library/Homebrew/test/dependency_spec.rb
+++ b/Library/Homebrew/test/dependency_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependency"
 
-describe Dependency do
+RSpec.describe Dependency do
   alias_matcher :be_a_build_dependency, :be_build
 
   describe "::new" do
diff --git a/Library/Homebrew/test/deprecate_disable_spec.rb b/Library/Homebrew/test/deprecate_disable_spec.rb
index 27b62458f9..790f34ae0e 100644
--- a/Library/Homebrew/test/deprecate_disable_spec.rb
+++ b/Library/Homebrew/test/deprecate_disable_spec.rb
@@ -2,7 +2,7 @@
 
 require "deprecate_disable"
 
-describe DeprecateDisable do
+RSpec.describe DeprecateDisable do
   let(:deprecated_formula) do
     instance_double(Formula, deprecated?: true, disabled?: false, deprecation_reason: :does_not_build)
   end
diff --git a/Library/Homebrew/test/description_cache_store_spec.rb b/Library/Homebrew/test/description_cache_store_spec.rb
index e4abc807fa..f5a3ccff17 100644
--- a/Library/Homebrew/test/description_cache_store_spec.rb
+++ b/Library/Homebrew/test/description_cache_store_spec.rb
@@ -3,7 +3,7 @@
 require "cmd/update-report"
 require "description_cache_store"
 
-describe DescriptionCacheStore do
+RSpec.describe DescriptionCacheStore do
   subject(:cache_store) { described_class.new(database) }
 
   let(:database) { instance_double(CacheStoreDatabase, "database") }
diff --git a/Library/Homebrew/test/descriptions_spec.rb b/Library/Homebrew/test/descriptions_spec.rb
index 05b35b1d8a..1bbfcf0ed1 100644
--- a/Library/Homebrew/test/descriptions_spec.rb
+++ b/Library/Homebrew/test/descriptions_spec.rb
@@ -2,7 +2,7 @@
 
 require "descriptions"
 
-describe Descriptions do
+RSpec.describe Descriptions do
   subject(:descriptions) { described_class.new(descriptions_hash) }
 
   let(:descriptions_hash) { {} }
diff --git a/Library/Homebrew/test/dev-cmd/audit_spec.rb b/Library/Homebrew/test/dev-cmd/audit_spec.rb
index 64df3df3d4..1c95aa58a3 100644
--- a/Library/Homebrew/test/dev-cmd/audit_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/audit_spec.rb
@@ -5,7 +5,7 @@ require "formulary"
 require "cmd/shared_examples/args_parse"
 require "utils/spdx"
 
-describe "brew audit" do
+RSpec.describe "brew audit" do
   it_behaves_like "parseable arguments"
 end
 
diff --git a/Library/Homebrew/test/dev-cmd/bottle_spec.rb b/Library/Homebrew/test/dev-cmd/bottle_spec.rb
index 9f463a1508..7fa0034952 100644
--- a/Library/Homebrew/test/dev-cmd/bottle_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bottle_spec.rb
@@ -3,7 +3,7 @@
 require "cmd/shared_examples/args_parse"
 require "dev-cmd/bottle"
 
-describe "brew bottle" do
+RSpec.describe "brew bottle" do
   def stub_hash(parameters)
     <<~EOS
       {
diff --git a/Library/Homebrew/test/dev-cmd/bump-cask-pr_spec.rb b/Library/Homebrew/test/dev-cmd/bump-cask-pr_spec.rb
index db2d071757..9a8b296c95 100644
--- a/Library/Homebrew/test/dev-cmd/bump-cask-pr_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bump-cask-pr_spec.rb
@@ -3,6 +3,6 @@
 require "cmd/shared_examples/args_parse"
 require "dev-cmd/bump-cask-pr"
 
-describe "brew bump-cask-pr" do
+RSpec.describe "brew bump-cask-pr" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/bump-formula-pr_spec.rb b/Library/Homebrew/test/dev-cmd/bump-formula-pr_spec.rb
index e8c0137b3a..8a141d220a 100644
--- a/Library/Homebrew/test/dev-cmd/bump-formula-pr_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bump-formula-pr_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew bump-formula-pr" do
+RSpec.describe "brew bump-formula-pr" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/bump-revision_spec.rb b/Library/Homebrew/test/dev-cmd/bump-revision_spec.rb
index f4c76e60d3..13d9833bf0 100644
--- a/Library/Homebrew/test/dev-cmd/bump-revision_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bump-revision_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew bump-revision" do
+RSpec.describe "brew bump-revision" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/bump-unversioned-casks_spec.rb b/Library/Homebrew/test/dev-cmd/bump-unversioned-casks_spec.rb
index b1f018564b..578deae573 100644
--- a/Library/Homebrew/test/dev-cmd/bump-unversioned-casks_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bump-unversioned-casks_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew bump-unversioned-casks" do
+RSpec.describe "brew bump-unversioned-casks" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/bump_spec.rb b/Library/Homebrew/test/dev-cmd/bump_spec.rb
index 1732192954..f576b23efb 100644
--- a/Library/Homebrew/test/dev-cmd/bump_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/bump_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew bump" do
+RSpec.describe "brew bump" do
   it_behaves_like "parseable arguments"
 
   describe "formula", :integration_test, :needs_homebrew_curl, :needs_network do
diff --git a/Library/Homebrew/test/dev-cmd/cat_spec.rb b/Library/Homebrew/test/dev-cmd/cat_spec.rb
index 0d5702094a..162e3d4f3d 100644
--- a/Library/Homebrew/test/dev-cmd/cat_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/cat_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew cat" do
+RSpec.describe "brew cat" do
   it_behaves_like "parseable arguments"
 
   it "prints the content of a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/command_spec.rb b/Library/Homebrew/test/dev-cmd/command_spec.rb
index 49418cbb99..05469f698f 100644
--- a/Library/Homebrew/test/dev-cmd/command_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/command_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew command" do
+RSpec.describe "brew command" do
   it_behaves_like "parseable arguments"
 
   it "returns the file for a given command", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/contributions_spec.rb b/Library/Homebrew/test/dev-cmd/contributions_spec.rb
index 98db0c73a3..0433c95efa 100644
--- a/Library/Homebrew/test/dev-cmd/contributions_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/contributions_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew contributions" do
+RSpec.describe "brew contributions" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/create_spec.rb b/Library/Homebrew/test/dev-cmd/create_spec.rb
index e0026dd19f..380c569fe6 100644
--- a/Library/Homebrew/test/dev-cmd/create_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/create_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew create" do
+RSpec.describe "brew create" do
   let(:url) { "file://#{TEST_FIXTURE_DIR}/tarballs/testball-0.1.tbz" }
   let(:formula_file) { CoreTap.new.new_formula_path("testball") }
 
diff --git a/Library/Homebrew/test/dev-cmd/determine-test-runners_spec.rb b/Library/Homebrew/test/dev-cmd/determine-test-runners_spec.rb
index 9eebdbb66b..4241778350 100644
--- a/Library/Homebrew/test/dev-cmd/determine-test-runners_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/determine-test-runners_spec.rb
@@ -3,7 +3,7 @@
 require "dev-cmd/determine-test-runners"
 require "cmd/shared_examples/args_parse"
 
-describe "brew determine-test-runners" do
+RSpec.describe "brew determine-test-runners" do
   def get_runners(file)
     runner_line = File.open(file).first
     json_text = runner_line[/runners=(.*)/, 1]
diff --git a/Library/Homebrew/test/dev-cmd/dispatch-build-bottle_spec.rb b/Library/Homebrew/test/dev-cmd/dispatch-build-bottle_spec.rb
index cfc4c21c64..e3fad4df2e 100644
--- a/Library/Homebrew/test/dev-cmd/dispatch-build-bottle_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/dispatch-build-bottle_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew dispatch-build-bottle" do
+RSpec.describe "brew dispatch-build-bottle" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/edit_spec.rb b/Library/Homebrew/test/dev-cmd/edit_spec.rb
index d406086b00..09ccfbdc24 100644
--- a/Library/Homebrew/test/dev-cmd/edit_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/edit_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew edit" do
+RSpec.describe "brew edit" do
   it_behaves_like "parseable arguments"
 
   it "opens a given Formula in an editor", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/extract_spec.rb b/Library/Homebrew/test/dev-cmd/extract_spec.rb
index f3d6910466..1a8a1a6e22 100644
--- a/Library/Homebrew/test/dev-cmd/extract_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/extract_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew extract" do
+RSpec.describe "brew extract" do
   it_behaves_like "parseable arguments"
 
   context "when extracting a formula" do
diff --git a/Library/Homebrew/test/dev-cmd/formula_spec.rb b/Library/Homebrew/test/dev-cmd/formula_spec.rb
index efe9d3daa6..73949595a3 100644
--- a/Library/Homebrew/test/dev-cmd/formula_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/formula_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew formula" do
+RSpec.describe "brew formula" do
   it_behaves_like "parseable arguments"
 
   it "prints a given Formula's path", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/generate-cask-api_spec.rb b/Library/Homebrew/test/dev-cmd/generate-cask-api_spec.rb
index 39a29b7385..08db0a6083 100644
--- a/Library/Homebrew/test/dev-cmd/generate-cask-api_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/generate-cask-api_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew generate-cask-api" do
+RSpec.describe "brew generate-cask-api" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/generate-formula-api_spec.rb b/Library/Homebrew/test/dev-cmd/generate-formula-api_spec.rb
index 7afd9a13c9..26958bffa6 100644
--- a/Library/Homebrew/test/dev-cmd/generate-formula-api_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/generate-formula-api_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew generate-formula-api" do
+RSpec.describe "brew generate-formula-api" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/generate-man-completions_spec.rb b/Library/Homebrew/test/dev-cmd/generate-man-completions_spec.rb
index 6b913fb43a..154790498a 100644
--- a/Library/Homebrew/test/dev-cmd/generate-man-completions_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/generate-man-completions_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew generate-man-completions" do
+RSpec.describe "brew generate-man-completions" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/irb_spec.rb b/Library/Homebrew/test/dev-cmd/irb_spec.rb
index 1ab33d935f..5ede76a455 100644
--- a/Library/Homebrew/test/dev-cmd/irb_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/irb_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew irb" do
+RSpec.describe "brew irb" do
   it_behaves_like "parseable arguments"
 
   describe "integration test" do
diff --git a/Library/Homebrew/test/dev-cmd/linkage_spec.rb b/Library/Homebrew/test/dev-cmd/linkage_spec.rb
index 4e1902d671..2318f53bff 100644
--- a/Library/Homebrew/test/dev-cmd/linkage_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/linkage_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew linkage" do
+RSpec.describe "brew linkage" do
   it_behaves_like "parseable arguments"
 
   it "works when no arguments are provided", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/livecheck_spec.rb b/Library/Homebrew/test/dev-cmd/livecheck_spec.rb
index 2496fa660b..686eb3a8da 100644
--- a/Library/Homebrew/test/dev-cmd/livecheck_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/livecheck_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew livecheck" do
+RSpec.describe "brew livecheck" do
   it_behaves_like "parseable arguments"
 
   it "reports the latest version of a Formula", :integration_test, :needs_network do
diff --git a/Library/Homebrew/test/dev-cmd/pr-automerge_spec.rb b/Library/Homebrew/test/dev-cmd/pr-automerge_spec.rb
index 188917cf83..261df7db89 100644
--- a/Library/Homebrew/test/dev-cmd/pr-automerge_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/pr-automerge_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew pr-automerge" do
+RSpec.describe "brew pr-automerge" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/pr-publish_spec.rb b/Library/Homebrew/test/dev-cmd/pr-publish_spec.rb
index 59262cd010..91dbc30a9c 100644
--- a/Library/Homebrew/test/dev-cmd/pr-publish_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/pr-publish_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew pr-publish" do
+RSpec.describe "brew pr-publish" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/pr-pull_spec.rb b/Library/Homebrew/test/dev-cmd/pr-pull_spec.rb
index 5b57b96a13..72550c4254 100644
--- a/Library/Homebrew/test/dev-cmd/pr-pull_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/pr-pull_spec.rb
@@ -5,7 +5,7 @@ require "utils/git"
 require "tap"
 require "cmd/shared_examples/args_parse"
 
-describe "brew pr-pull" do
+RSpec.describe "brew pr-pull" do
   it_behaves_like "parseable arguments"
 
   describe Homebrew do
diff --git a/Library/Homebrew/test/dev-cmd/pr-upload_spec.rb b/Library/Homebrew/test/dev-cmd/pr-upload_spec.rb
index 35de7d2b16..dfac35a539 100644
--- a/Library/Homebrew/test/dev-cmd/pr-upload_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/pr-upload_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew pr-upload" do
+RSpec.describe "brew pr-upload" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/prof_spec.rb b/Library/Homebrew/test/dev-cmd/prof_spec.rb
index eaf0e18ab0..25565776d1 100644
--- a/Library/Homebrew/test/dev-cmd/prof_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/prof_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew prof" do
+RSpec.describe "brew prof" do
   it_behaves_like "parseable arguments"
 
   describe "integration tests", :integration_test, :needs_network do
diff --git a/Library/Homebrew/test/dev-cmd/release_spec.rb b/Library/Homebrew/test/dev-cmd/release_spec.rb
index 0031116bd4..a46d08ebd0 100644
--- a/Library/Homebrew/test/dev-cmd/release_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/release_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew release" do
+RSpec.describe "brew release" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/ruby_spec.rb b/Library/Homebrew/test/dev-cmd/ruby_spec.rb
index 1d5397ca4d..076bf01eb6 100644
--- a/Library/Homebrew/test/dev-cmd/ruby_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/ruby_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew ruby" do
+RSpec.describe "brew ruby" do
   it_behaves_like "parseable arguments"
 
   it "executes ruby code with Homebrew's libraries loaded", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/sh_spec.rb b/Library/Homebrew/test/dev-cmd/sh_spec.rb
index 7761cb9964..e2a690a854 100644
--- a/Library/Homebrew/test/dev-cmd/sh_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/sh_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew sh" do
+RSpec.describe "brew sh" do
   it_behaves_like "parseable arguments"
 
   it "runs a shell with the Homebrew environment", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/style_spec.rb b/Library/Homebrew/test/dev-cmd/style_spec.rb
index b4d9f67d11..10e987883a 100644
--- a/Library/Homebrew/test/dev-cmd/style_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/style_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew style" do
+RSpec.describe "brew style" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/tap-new_spec.rb b/Library/Homebrew/test/dev-cmd/tap-new_spec.rb
index 64fe7326cd..a79d356507 100644
--- a/Library/Homebrew/test/dev-cmd/tap-new_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/tap-new_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew tap-new" do
+RSpec.describe "brew tap-new" do
   it_behaves_like "parseable arguments"
 
   it "initializes a new tap with a README file and GitHub Actions CI", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/test_spec.rb b/Library/Homebrew/test/dev-cmd/test_spec.rb
index fccb80a374..baed50a221 100644
--- a/Library/Homebrew/test/dev-cmd/test_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/test_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew test" do
+RSpec.describe "brew test" do
   it_behaves_like "parseable arguments"
 
   it "tests a given Formula", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/typecheck_spec.rb b/Library/Homebrew/test/dev-cmd/typecheck_spec.rb
index a7c09740b5..1838b4bda1 100644
--- a/Library/Homebrew/test/dev-cmd/typecheck_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/typecheck_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew typecheck" do
+RSpec.describe "brew typecheck" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/unbottled_spec.rb b/Library/Homebrew/test/dev-cmd/unbottled_spec.rb
index 438f2fa00c..508574033e 100644
--- a/Library/Homebrew/test/dev-cmd/unbottled_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/unbottled_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew unbottled" do
+RSpec.describe "brew unbottled" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/unpack_spec.rb b/Library/Homebrew/test/dev-cmd/unpack_spec.rb
index 7c65583652..b00d51ce04 100644
--- a/Library/Homebrew/test/dev-cmd/unpack_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/unpack_spec.rb
@@ -2,7 +2,7 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew unpack" do
+RSpec.describe "brew unpack" do
   it_behaves_like "parseable arguments"
 
   it "unpacks a given Formula's archive", :integration_test do
diff --git a/Library/Homebrew/test/dev-cmd/update-license-data_spec.rb b/Library/Homebrew/test/dev-cmd/update-license-data_spec.rb
index 7c292cbabc..0acb9110ce 100644
--- a/Library/Homebrew/test/dev-cmd/update-license-data_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/update-license-data_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew update-license-data" do
+RSpec.describe "brew update-license-data" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/update-maintainers_spec.rb b/Library/Homebrew/test/dev-cmd/update-maintainers_spec.rb
index 122e60f43b..a58eed3bc6 100644
--- a/Library/Homebrew/test/dev-cmd/update-maintainers_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/update-maintainers_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew update-maintainers" do
+RSpec.describe "brew update-maintainers" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/update-python-resources_spec.rb b/Library/Homebrew/test/dev-cmd/update-python-resources_spec.rb
index 372d0f88fe..9b304adf39 100644
--- a/Library/Homebrew/test/dev-cmd/update-python-resources_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/update-python-resources_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew update-python-resources" do
+RSpec.describe "brew update-python-resources" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/update-sponsors_spec.rb b/Library/Homebrew/test/dev-cmd/update-sponsors_spec.rb
index 58323e5975..092805a99f 100644
--- a/Library/Homebrew/test/dev-cmd/update-sponsors_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/update-sponsors_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew update-sponsors" do
+RSpec.describe "brew update-sponsors" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/dev-cmd/vendor-gems_spec.rb b/Library/Homebrew/test/dev-cmd/vendor-gems_spec.rb
index 5ca8837f28..c9ef4c4fd3 100644
--- a/Library/Homebrew/test/dev-cmd/vendor-gems_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/vendor-gems_spec.rb
@@ -2,6 +2,6 @@
 
 require "cmd/shared_examples/args_parse"
 
-describe "brew vendor-gems" do
+RSpec.describe "brew vendor-gems" do
   it_behaves_like "parseable arguments"
 end
diff --git a/Library/Homebrew/test/diagnostic_checks_spec.rb b/Library/Homebrew/test/diagnostic_checks_spec.rb
index d04c5d9a52..817d8a7306 100644
--- a/Library/Homebrew/test/diagnostic_checks_spec.rb
+++ b/Library/Homebrew/test/diagnostic_checks_spec.rb
@@ -2,7 +2,7 @@
 
 require "diagnostic"
 
-describe Homebrew::Diagnostic::Checks do
+RSpec.describe Homebrew::Diagnostic::Checks do
   subject(:checks) { described_class.new }
 
   specify "#inject_file_list" do
diff --git a/Library/Homebrew/test/download_strategies/abstract_spec.rb b/Library/Homebrew/test/download_strategies/abstract_spec.rb
index c943c2131e..e58b15b49f 100644
--- a/Library/Homebrew/test/download_strategies/abstract_spec.rb
+++ b/Library/Homebrew/test/download_strategies/abstract_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe AbstractDownloadStrategy do
+RSpec.describe AbstractDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:specs) { {} }
diff --git a/Library/Homebrew/test/download_strategies/curl_github_packages_spec.rb b/Library/Homebrew/test/download_strategies/curl_github_packages_spec.rb
index 35d82e6dd4..0828ee26c6 100644
--- a/Library/Homebrew/test/download_strategies/curl_github_packages_spec.rb
+++ b/Library/Homebrew/test/download_strategies/curl_github_packages_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe CurlGitHubPackagesDownloadStrategy do
+RSpec.describe CurlGitHubPackagesDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
diff --git a/Library/Homebrew/test/download_strategies/curl_post_spec.rb b/Library/Homebrew/test/download_strategies/curl_post_spec.rb
index 33bc2ba94c..20b382736c 100644
--- a/Library/Homebrew/test/download_strategies/curl_post_spec.rb
+++ b/Library/Homebrew/test/download_strategies/curl_post_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe CurlPostDownloadStrategy do
+RSpec.describe CurlPostDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
diff --git a/Library/Homebrew/test/download_strategies/curl_spec.rb b/Library/Homebrew/test/download_strategies/curl_spec.rb
index ff94c94f7e..08007ef84b 100644
--- a/Library/Homebrew/test/download_strategies/curl_spec.rb
+++ b/Library/Homebrew/test/download_strategies/curl_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe CurlDownloadStrategy do
+RSpec.describe CurlDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
diff --git a/Library/Homebrew/test/download_strategies/detector_spec.rb b/Library/Homebrew/test/download_strategies/detector_spec.rb
index 24e1a42db7..7bf0604fe7 100644
--- a/Library/Homebrew/test/download_strategies/detector_spec.rb
+++ b/Library/Homebrew/test/download_strategies/detector_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe DownloadStrategyDetector do
+RSpec.describe DownloadStrategyDetector do
   describe "::detect" do
     subject(:strategy_detector) { described_class.detect(url, strategy) }
 
diff --git a/Library/Homebrew/test/download_strategies/git_spec.rb b/Library/Homebrew/test/download_strategies/git_spec.rb
index 6a8eb82b65..42f1fdaeb4 100644
--- a/Library/Homebrew/test/download_strategies/git_spec.rb
+++ b/Library/Homebrew/test/download_strategies/git_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe GitDownloadStrategy do
+RSpec.describe GitDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version) }
 
   let(:name) { "baz" }
diff --git a/Library/Homebrew/test/download_strategies/github_git_spec.rb b/Library/Homebrew/test/download_strategies/github_git_spec.rb
index 63c6a4789e..27ef115257 100644
--- a/Library/Homebrew/test/download_strategies/github_git_spec.rb
+++ b/Library/Homebrew/test/download_strategies/github_git_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe GitHubGitDownloadStrategy do
+RSpec.describe GitHubGitDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version) }
 
   let(:name) { "brew" }
diff --git a/Library/Homebrew/test/download_strategies/subversion_spec.rb b/Library/Homebrew/test/download_strategies/subversion_spec.rb
index 21ac18c865..c1f08caf16 100644
--- a/Library/Homebrew/test/download_strategies/subversion_spec.rb
+++ b/Library/Homebrew/test/download_strategies/subversion_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe SubversionDownloadStrategy do
+RSpec.describe SubversionDownloadStrategy do
   subject(:strategy) { described_class.new(url, name, version, **specs) }
 
   let(:name) { "foo" }
diff --git a/Library/Homebrew/test/download_strategies/vcs_spec.rb b/Library/Homebrew/test/download_strategies/vcs_spec.rb
index 24dea6758a..4f564a6133 100644
--- a/Library/Homebrew/test/download_strategies/vcs_spec.rb
+++ b/Library/Homebrew/test/download_strategies/vcs_spec.rb
@@ -2,7 +2,7 @@
 
 require "download_strategy"
 
-describe VCSDownloadStrategy do
+RSpec.describe VCSDownloadStrategy do
   let(:url) { "https://example.com/bar" }
   let(:version) { nil }
 
diff --git a/Library/Homebrew/test/env_config_spec.rb b/Library/Homebrew/test/env_config_spec.rb
index 814f8f2ca8..02fdd05948 100644
--- a/Library/Homebrew/test/env_config_spec.rb
+++ b/Library/Homebrew/test/env_config_spec.rb
@@ -2,7 +2,7 @@
 
 require "diagnostic"
 
-describe Homebrew::EnvConfig do
+RSpec.describe Homebrew::EnvConfig do
   subject(:env_config) { described_class }
 
   describe ".env_method_name" do
diff --git a/Library/Homebrew/test/error_during_execution_spec.rb b/Library/Homebrew/test/error_during_execution_spec.rb
index ea8e3cc7d4..5407bce8e4 100644
--- a/Library/Homebrew/test/error_during_execution_spec.rb
+++ b/Library/Homebrew/test/error_during_execution_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe ErrorDuringExecution do
+RSpec.describe ErrorDuringExecution do
   subject(:error) { described_class.new(command, status: status, output: output) }
 
   let(:command) { ["false"] }
diff --git a/Library/Homebrew/test/exceptions_spec.rb b/Library/Homebrew/test/exceptions_spec.rb
index a56fbb914c..f93a853d8c 100644
--- a/Library/Homebrew/test/exceptions_spec.rb
+++ b/Library/Homebrew/test/exceptions_spec.rb
@@ -2,7 +2,7 @@
 
 require "exceptions"
 
-describe "Exception" do
+RSpec.describe "Exception" do
   describe MultipleVersionsInstalledError do
     subject do
       described_class.new <<~EOS
diff --git a/Library/Homebrew/test/extend/array_spec.rb b/Library/Homebrew/test/extend/array_spec.rb
index 385c27a546..deac14ec6a 100644
--- a/Library/Homebrew/test/extend/array_spec.rb
+++ b/Library/Homebrew/test/extend/array_spec.rb
@@ -2,7 +2,7 @@
 
 require "extend/array"
 
-describe Array do
+RSpec.describe Array do
   describe ".to_sentence" do
     it "converts a plain array to a sentence" do
       expect([].to_sentence).to eq("")
diff --git a/Library/Homebrew/test/extend/blank_spec.rb b/Library/Homebrew/test/extend/blank_spec.rb
index 5dfae89845..6c5d466692 100644
--- a/Library/Homebrew/test/extend/blank_spec.rb
+++ b/Library/Homebrew/test/extend/blank_spec.rb
@@ -2,7 +2,7 @@
 
 require "extend/blank"
 
-describe Object do
+RSpec.describe Object do
   let(:empty_true) do
     Class.new(described_class) do
       def empty?
diff --git a/Library/Homebrew/test/extend/kernel_spec.rb b/Library/Homebrew/test/extend/kernel_spec.rb
index 0dbaae1fd2..eb81687878 100644
--- a/Library/Homebrew/test/extend/kernel_spec.rb
+++ b/Library/Homebrew/test/extend/kernel_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "globally-scoped helper methods" do
+RSpec.describe "globally-scoped helper methods" do
   let(:dir) { mktmpdir }
 
   def esc(code)
diff --git a/Library/Homebrew/test/formatter_spec.rb b/Library/Homebrew/test/formatter_spec.rb
index 84637459fe..e02451a594 100644
--- a/Library/Homebrew/test/formatter_spec.rb
+++ b/Library/Homebrew/test/formatter_spec.rb
@@ -3,7 +3,7 @@
 require "utils/formatter"
 require "utils/tty"
 
-describe Formatter do
+RSpec.describe Formatter do
   describe "::columns" do
     subject(:columns) { described_class.columns(input) }
 
diff --git a/Library/Homebrew/test/formula_creator_spec.rb b/Library/Homebrew/test/formula_creator_spec.rb
index 9c48392949..a708686406 100644
--- a/Library/Homebrew/test/formula_creator_spec.rb
+++ b/Library/Homebrew/test/formula_creator_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula_creator"
 
-describe Homebrew::FormulaCreator do
+RSpec.describe Homebrew::FormulaCreator do
   it "gets name from GitHub archive URL" do
     t = described_class.name_from_url("https://github.com/abitrolly/lapce/archive/v0.3.0.tar.gz")
     expect(t).to eq("lapce")
diff --git a/Library/Homebrew/test/formula_info_spec.rb b/Library/Homebrew/test/formula_info_spec.rb
index f9eb8b3d9b..e42620b669 100644
--- a/Library/Homebrew/test/formula_info_spec.rb
+++ b/Library/Homebrew/test/formula_info_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula_info"
 
-describe FormulaInfo, :integration_test do
+RSpec.describe FormulaInfo, :integration_test do
   it "tests the FormulaInfo class" do
     install_test_formula "testball"
 
diff --git a/Library/Homebrew/test/formula_installer_bottle_spec.rb b/Library/Homebrew/test/formula_installer_bottle_spec.rb
index befc23d388..17ca53d48a 100644
--- a/Library/Homebrew/test/formula_installer_bottle_spec.rb
+++ b/Library/Homebrew/test/formula_installer_bottle_spec.rb
@@ -9,7 +9,7 @@ require "test/support/fixtures/testball"
 require "test/support/fixtures/testball_bottle"
 require "test/support/fixtures/testball_bottle_cellar"
 
-describe FormulaInstaller do
+RSpec.describe FormulaInstaller do
   alias_matcher :pour_bottle, :be_pour_bottle
 
   matcher :be_poured_from_bottle do
diff --git a/Library/Homebrew/test/formula_installer_spec.rb b/Library/Homebrew/test/formula_installer_spec.rb
index 5a3ebb72d3..13ba7871e5 100644
--- a/Library/Homebrew/test/formula_installer_spec.rb
+++ b/Library/Homebrew/test/formula_installer_spec.rb
@@ -9,7 +9,7 @@ require "test/support/fixtures/testball"
 require "test/support/fixtures/testball_bottle"
 require "test/support/fixtures/failball"
 
-describe FormulaInstaller do
+RSpec.describe FormulaInstaller do
   matcher :be_poured_from_bottle do
     match(&:poured_from_bottle)
   end
diff --git a/Library/Homebrew/test/formula_pin_spec.rb b/Library/Homebrew/test/formula_pin_spec.rb
index e0c0ca676b..c17b6f81ce 100644
--- a/Library/Homebrew/test/formula_pin_spec.rb
+++ b/Library/Homebrew/test/formula_pin_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula_pin"
 
-describe FormulaPin do
+RSpec.describe FormulaPin do
   subject(:formula_pin) { described_class.new(formula) }
 
   let(:name) { "double" }
diff --git a/Library/Homebrew/test/formula_spec.rb b/Library/Homebrew/test/formula_spec.rb
index 414b6004dd..3175505bc6 100644
--- a/Library/Homebrew/test/formula_spec.rb
+++ b/Library/Homebrew/test/formula_spec.rb
@@ -3,7 +3,7 @@
 require "test/support/fixtures/testball"
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   alias_matcher :follow_installed_alias, :be_follow_installed_alias
   alias_matcher :have_any_version_installed, :be_any_version_installed
   alias_matcher :need_migration, :be_migration_needed
diff --git a/Library/Homebrew/test/formula_spec_selection_spec.rb b/Library/Homebrew/test/formula_spec_selection_spec.rb
index a03f11b96b..72f565a48a 100644
--- a/Library/Homebrew/test/formula_spec_selection_spec.rb
+++ b/Library/Homebrew/test/formula_spec_selection_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   describe "::new" do
     it "selects stable by default" do
       f = formula do
diff --git a/Library/Homebrew/test/formula_support/keg_only_reason_spec.rb b/Library/Homebrew/test/formula_support/keg_only_reason_spec.rb
index 3574e93dfc..ca669b5365 100644
--- a/Library/Homebrew/test/formula_support/keg_only_reason_spec.rb
+++ b/Library/Homebrew/test/formula_support/keg_only_reason_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula_support"
 
-describe KegOnlyReason do
+RSpec.describe KegOnlyReason do
   describe "#to_s" do
     it "returns the reason provided" do
       r = described_class.new :provided_by_macos, "test"
diff --git a/Library/Homebrew/test/formula_validation_spec.rb b/Library/Homebrew/test/formula_validation_spec.rb
index 8e2a08bd11..e6388fc25f 100644
--- a/Library/Homebrew/test/formula_validation_spec.rb
+++ b/Library/Homebrew/test/formula_validation_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   describe "::new" do
     matcher :fail_with_invalid do |attr|
       match do |actual|
diff --git a/Library/Homebrew/test/formulary_spec.rb b/Library/Homebrew/test/formulary_spec.rb
index 07903bbc4a..abbdd74534 100644
--- a/Library/Homebrew/test/formulary_spec.rb
+++ b/Library/Homebrew/test/formulary_spec.rb
@@ -4,7 +4,7 @@ require "formula"
 require "formula_installer"
 require "utils/bottles"
 
-describe Formulary do
+RSpec.describe Formulary do
   let(:formula_name) { "testball_bottle" }
   let(:formula_path) { CoreTap.new.new_formula_path(formula_name) }
   let(:formula_content) do
diff --git a/Library/Homebrew/test/github_runner_matrix_spec.rb b/Library/Homebrew/test/github_runner_matrix_spec.rb
index 00bccd4981..01bed6f608 100644
--- a/Library/Homebrew/test/github_runner_matrix_spec.rb
+++ b/Library/Homebrew/test/github_runner_matrix_spec.rb
@@ -3,7 +3,7 @@
 require "github_runner_matrix"
 require "test/support/fixtures/testball"
 
-describe GitHubRunnerMatrix do
+RSpec.describe GitHubRunnerMatrix do
   before do
     allow(ENV).to receive(:fetch).with("HOMEBREW_LINUX_RUNNER").and_return("ubuntu-latest")
     allow(ENV).to receive(:fetch).with("HOMEBREW_MACOS_TIMEOUT").and_return("90")
diff --git a/Library/Homebrew/test/github_runner_spec.rb b/Library/Homebrew/test/github_runner_spec.rb
index 7859b0325b..d0597db86c 100644
--- a/Library/Homebrew/test/github_runner_spec.rb
+++ b/Library/Homebrew/test/github_runner_spec.rb
@@ -2,7 +2,7 @@
 
 require "github_runner"
 
-describe GitHubRunner do
+RSpec.describe GitHubRunner do
   let(:runner) do
     spec = MacOSRunnerSpec.new(name: "macOS 11-arm64", runner: "11-arm64", timeout: 90, cleanup: true)
     version = MacOSVersion.new("11")
diff --git a/Library/Homebrew/test/global_spec.rb b/Library/Homebrew/test/global_spec.rb
index 5ae60e6662..76abb380f0 100644
--- a/Library/Homebrew/test/global_spec.rb
+++ b/Library/Homebrew/test/global_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "brew", :integration_test do
+RSpec.describe "brew", :integration_test do
   it "does not invoke `require \"formula\"` at startup" do
     expect { brew "verify-formula-undefined" }
       .to not_to_output.to_stdout
diff --git a/Library/Homebrew/test/hardware/cpu_spec.rb b/Library/Homebrew/test/hardware/cpu_spec.rb
index 0c971eb9de..a8c11bb31e 100644
--- a/Library/Homebrew/test/hardware/cpu_spec.rb
+++ b/Library/Homebrew/test/hardware/cpu_spec.rb
@@ -2,7 +2,7 @@
 
 require "hardware"
 
-describe Hardware::CPU do
+RSpec.describe Hardware::CPU do
   describe "::type" do
     let(:cpu_types) do
       [
diff --git a/Library/Homebrew/test/installed_dependents_spec.rb b/Library/Homebrew/test/installed_dependents_spec.rb
index 04c5f5beaa..5df0b532c1 100644
--- a/Library/Homebrew/test/installed_dependents_spec.rb
+++ b/Library/Homebrew/test/installed_dependents_spec.rb
@@ -2,7 +2,7 @@
 
 require "installed_dependents"
 
-describe InstalledDependents do
+RSpec.describe InstalledDependents do
   include FileUtils
 
   def stub_formula(name, version = "1.0", &block)
diff --git a/Library/Homebrew/test/keg_relocate/binary_relocation_spec.rb b/Library/Homebrew/test/keg_relocate/binary_relocation_spec.rb
index d9eb2d5baa..652eac1168 100644
--- a/Library/Homebrew/test/keg_relocate/binary_relocation_spec.rb
+++ b/Library/Homebrew/test/keg_relocate/binary_relocation_spec.rb
@@ -2,7 +2,7 @@
 
 require "keg_relocate"
 
-describe Keg do
+RSpec.describe Keg do
   subject(:keg) { described_class.new(HOMEBREW_CELLAR/"foo/1.0.0") }
 
   let(:dir) { HOMEBREW_CELLAR/"foo/1.0.0" }
diff --git a/Library/Homebrew/test/keg_relocate/grep_spec.rb b/Library/Homebrew/test/keg_relocate/grep_spec.rb
index 63e98f7429..1f834de7ec 100644
--- a/Library/Homebrew/test/keg_relocate/grep_spec.rb
+++ b/Library/Homebrew/test/keg_relocate/grep_spec.rb
@@ -2,7 +2,7 @@
 
 require "keg_relocate"
 
-describe Keg do
+RSpec.describe Keg do
   subject(:keg) { described_class.new(HOMEBREW_CELLAR/"foo/1.0.0") }
 
   let(:dir) { HOMEBREW_CELLAR/"foo/1.0.0" }
diff --git a/Library/Homebrew/test/keg_relocate/relocation_spec.rb b/Library/Homebrew/test/keg_relocate/relocation_spec.rb
index 42b824dc33..2faca61856 100644
--- a/Library/Homebrew/test/keg_relocate/relocation_spec.rb
+++ b/Library/Homebrew/test/keg_relocate/relocation_spec.rb
@@ -2,7 +2,7 @@
 
 require "keg_relocate"
 
-describe Keg::Relocation do
+RSpec.describe Keg::Relocation do
   let(:prefix) { HOMEBREW_PREFIX.to_s }
   let(:cellar) { HOMEBREW_CELLAR.to_s }
   let(:repository) { HOMEBREW_REPOSITORY.to_s }
diff --git a/Library/Homebrew/test/keg_relocate/text_spec.rb b/Library/Homebrew/test/keg_relocate/text_spec.rb
index 122d8fa4e8..8a53cbbf70 100644
--- a/Library/Homebrew/test/keg_relocate/text_spec.rb
+++ b/Library/Homebrew/test/keg_relocate/text_spec.rb
@@ -2,7 +2,7 @@
 
 require "keg_relocate"
 
-describe Keg do
+RSpec.describe Keg do
   subject(:keg) { described_class.new(HOMEBREW_CELLAR/"foo/1.0.0") }
 
   let(:dir) { mktmpdir }
diff --git a/Library/Homebrew/test/keg_spec.rb b/Library/Homebrew/test/keg_spec.rb
index c45bc9ea4b..5231fe619f 100644
--- a/Library/Homebrew/test/keg_spec.rb
+++ b/Library/Homebrew/test/keg_spec.rb
@@ -3,7 +3,7 @@
 require "keg"
 require "stringio"
 
-describe Keg do
+RSpec.describe Keg do
   def setup_test_keg(name, version)
     path = HOMEBREW_CELLAR/name/version
     (path/"bin").mkpath
diff --git a/Library/Homebrew/test/language/go_spec.rb b/Library/Homebrew/test/language/go_spec.rb
index ac631f38cc..d13bd56c13 100644
--- a/Library/Homebrew/test/language/go_spec.rb
+++ b/Library/Homebrew/test/language/go_spec.rb
@@ -2,7 +2,7 @@
 
 require "language/go"
 
-describe Language::Go do
+RSpec.describe Language::Go do
   specify "#stage_deps" do
     ENV.delete("HOMEBREW_DEVELOPER")
 
diff --git a/Library/Homebrew/test/language/java_spec.rb b/Library/Homebrew/test/language/java_spec.rb
index 13d3d15eb8..a61b2c5dd3 100644
--- a/Library/Homebrew/test/language/java_spec.rb
+++ b/Library/Homebrew/test/language/java_spec.rb
@@ -2,7 +2,7 @@
 
 require "language/java"
 
-describe Language::Java do
+RSpec.describe Language::Java do
   let(:f) do
     formula("openjdk") do
       url "openjdk"
diff --git a/Library/Homebrew/test/language/node/shebang_spec.rb b/Library/Homebrew/test/language/node/shebang_spec.rb
index e691f66976..4c282eab3d 100644
--- a/Library/Homebrew/test/language/node/shebang_spec.rb
+++ b/Library/Homebrew/test/language/node/shebang_spec.rb
@@ -3,7 +3,7 @@
 require "language/node"
 require "utils/shebang"
 
-describe Language::Node::Shebang do
+RSpec.describe Language::Node::Shebang do
   let(:file) { Tempfile.new("node-shebang") }
   let(:f) do
     f = {}
diff --git a/Library/Homebrew/test/language/node_spec.rb b/Library/Homebrew/test/language/node_spec.rb
index f024e223e7..0d02b8062b 100644
--- a/Library/Homebrew/test/language/node_spec.rb
+++ b/Library/Homebrew/test/language/node_spec.rb
@@ -2,7 +2,7 @@
 
 require "language/node"
 
-describe Language::Node do
+RSpec.describe Language::Node do
   let(:npm_pack_cmd) { ["npm", "pack", "--ignore-scripts"] }
 
   describe "#setup_npm_environment" do
diff --git a/Library/Homebrew/test/language/perl/shebang_spec.rb b/Library/Homebrew/test/language/perl/shebang_spec.rb
index 06ee219825..c08de4321d 100644
--- a/Library/Homebrew/test/language/perl/shebang_spec.rb
+++ b/Library/Homebrew/test/language/perl/shebang_spec.rb
@@ -3,7 +3,7 @@
 require "language/perl"
 require "utils/shebang"
 
-describe Language::Perl::Shebang do
+RSpec.describe Language::Perl::Shebang do
   let(:file) { Tempfile.new("perl-shebang") }
   let(:f) do
     f = {}
diff --git a/Library/Homebrew/test/language/python/shebang_spec.rb b/Library/Homebrew/test/language/python/shebang_spec.rb
index 4e430cc093..b6d3d22d97 100644
--- a/Library/Homebrew/test/language/python/shebang_spec.rb
+++ b/Library/Homebrew/test/language/python/shebang_spec.rb
@@ -3,7 +3,7 @@
 require "language/python"
 require "utils/shebang"
 
-describe Language::Python::Shebang do
+RSpec.describe Language::Python::Shebang do
   let(:file) { Tempfile.new("python-shebang") }
   let(:f) do
     f = {}
diff --git a/Library/Homebrew/test/language/python/virtualenv_spec.rb b/Library/Homebrew/test/language/python/virtualenv_spec.rb
index 458afc0394..0ef5ac6db5 100644
--- a/Library/Homebrew/test/language/python/virtualenv_spec.rb
+++ b/Library/Homebrew/test/language/python/virtualenv_spec.rb
@@ -3,7 +3,7 @@
 require "language/python"
 require "resource"
 
-describe Language::Python::Virtualenv::Virtualenv, :needs_python do
+RSpec.describe Language::Python::Virtualenv::Virtualenv, :needs_python do
   subject(:virtualenv) { described_class.new(formula, dir, "python") }
 
   let(:dir) { mktmpdir }
diff --git a/Library/Homebrew/test/language/python_spec.rb b/Library/Homebrew/test/language/python_spec.rb
index 49943f2923..d7472a91c1 100644
--- a/Library/Homebrew/test/language/python_spec.rb
+++ b/Library/Homebrew/test/language/python_spec.rb
@@ -2,7 +2,7 @@
 
 require "language/python"
 
-describe Language::Python, :needs_python do
+RSpec.describe Language::Python, :needs_python do
   describe "#major_minor_version" do
     it "returns a Version for Python 2" do
       expect(described_class).to receive(:major_minor_version).and_return(Version)
diff --git a/Library/Homebrew/test/lazy_object_spec.rb b/Library/Homebrew/test/lazy_object_spec.rb
index 8afb69e3cc..cd925f68a5 100644
--- a/Library/Homebrew/test/lazy_object_spec.rb
+++ b/Library/Homebrew/test/lazy_object_spec.rb
@@ -2,7 +2,7 @@
 
 require "lazy_object"
 
-describe LazyObject do
+RSpec.describe LazyObject do
   describe "#initialize" do
     it "does not evaluate the block" do
       expect do |block|
diff --git a/Library/Homebrew/test/linkage_cache_store_spec.rb b/Library/Homebrew/test/linkage_cache_store_spec.rb
index 23fc2a9229..fd3beab76f 100644
--- a/Library/Homebrew/test/linkage_cache_store_spec.rb
+++ b/Library/Homebrew/test/linkage_cache_store_spec.rb
@@ -2,7 +2,7 @@
 
 require "linkage_cache_store"
 
-describe LinkageCacheStore do
+RSpec.describe LinkageCacheStore do
   subject(:linkage_cache) { described_class.new(keg_name, database) }
 
   let(:keg_name) { "keg_name" }
diff --git a/Library/Homebrew/test/linux_runner_spec_spec.rb b/Library/Homebrew/test/linux_runner_spec_spec.rb
index 010b550790..8b986c1dd4 100644
--- a/Library/Homebrew/test/linux_runner_spec_spec.rb
+++ b/Library/Homebrew/test/linux_runner_spec_spec.rb
@@ -2,7 +2,7 @@
 
 require "linux_runner_spec"
 
-describe LinuxRunnerSpec do
+RSpec.describe LinuxRunnerSpec do
   let(:spec) do
     described_class.new(
       name:      "Linux",
diff --git a/Library/Homebrew/test/livecheck/livecheck_spec.rb b/Library/Homebrew/test/livecheck/livecheck_spec.rb
index 313a59bccc..34e048f510 100644
--- a/Library/Homebrew/test/livecheck/livecheck_spec.rb
+++ b/Library/Homebrew/test/livecheck/livecheck_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/livecheck"
 
-describe Homebrew::Livecheck do
+RSpec.describe Homebrew::Livecheck do
   subject(:livecheck) { described_class }
 
   let(:cask_url) { "https://brew.sh/test-0.0.1.dmg" }
diff --git a/Library/Homebrew/test/livecheck/livecheck_version_spec.rb b/Library/Homebrew/test/livecheck/livecheck_version_spec.rb
index 4307780418..b5c38fd78f 100644
--- a/Library/Homebrew/test/livecheck/livecheck_version_spec.rb
+++ b/Library/Homebrew/test/livecheck/livecheck_version_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/livecheck_version"
 
-describe Homebrew::Livecheck::LivecheckVersion do
+RSpec.describe Homebrew::Livecheck::LivecheckVersion do
   let(:formula) { instance_double(Formula) }
   let(:cask) { instance_double(Cask::Cask) }
   let(:resource) { instance_double(Resource) }
diff --git a/Library/Homebrew/test/livecheck/skip_conditions_spec.rb b/Library/Homebrew/test/livecheck/skip_conditions_spec.rb
index cb0c28fd9d..e174fbe3e7 100644
--- a/Library/Homebrew/test/livecheck/skip_conditions_spec.rb
+++ b/Library/Homebrew/test/livecheck/skip_conditions_spec.rb
@@ -3,7 +3,7 @@
 require "livecheck/livecheck"
 require "livecheck/skip_conditions"
 
-describe Homebrew::Livecheck::SkipConditions do
+RSpec.describe Homebrew::Livecheck::SkipConditions do
   subject(:skip_conditions) { described_class }
 
   let(:formulae) do
diff --git a/Library/Homebrew/test/livecheck/strategy/apache_spec.rb b/Library/Homebrew/test/livecheck/strategy/apache_spec.rb
index 624ddaedfb..befc0b55cd 100644
--- a/Library/Homebrew/test/livecheck/strategy/apache_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/apache_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Apache do
+RSpec.describe Homebrew::Livecheck::Strategy::Apache do
   subject(:apache) { described_class }
 
   let(:apache_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/bitbucket_spec.rb b/Library/Homebrew/test/livecheck/strategy/bitbucket_spec.rb
index 612dc58f32..a0a9c3eb47 100644
--- a/Library/Homebrew/test/livecheck/strategy/bitbucket_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/bitbucket_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Bitbucket do
+RSpec.describe Homebrew::Livecheck::Strategy::Bitbucket do
   subject(:bitbucket) { described_class }
 
   let(:bitbucket_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/cpan_spec.rb b/Library/Homebrew/test/livecheck/strategy/cpan_spec.rb
index db0fc54909..b1dafb6fb9 100644
--- a/Library/Homebrew/test/livecheck/strategy/cpan_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/cpan_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Cpan do
+RSpec.describe Homebrew::Livecheck::Strategy::Cpan do
   subject(:cpan) { described_class }
 
   let(:cpan_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/crate_spec.rb b/Library/Homebrew/test/livecheck/strategy/crate_spec.rb
index 0f3dd87c4a..0333d73514 100644
--- a/Library/Homebrew/test/livecheck/strategy/crate_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/crate_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Crate do
+RSpec.describe Homebrew::Livecheck::Strategy::Crate do
   subject(:crate) { described_class }
 
   let(:crate_url) { "https://static.crates.io/crates/example/example-0.1.0.crate" }
diff --git a/Library/Homebrew/test/livecheck/strategy/electron_builder_spec.rb b/Library/Homebrew/test/livecheck/strategy/electron_builder_spec.rb
index b129ed5a59..403eb2e2e2 100644
--- a/Library/Homebrew/test/livecheck/strategy/electron_builder_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/electron_builder_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::ElectronBuilder do
+RSpec.describe Homebrew::Livecheck::Strategy::ElectronBuilder do
   subject(:electron_builder) { described_class }
 
   let(:http_url) { "https://www.example.com/example/latest-mac.yml" }
diff --git a/Library/Homebrew/test/livecheck/strategy/extract_plist_spec.rb b/Library/Homebrew/test/livecheck/strategy/extract_plist_spec.rb
index 1543498b84..8165439c4e 100644
--- a/Library/Homebrew/test/livecheck/strategy/extract_plist_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/extract_plist_spec.rb
@@ -3,7 +3,7 @@
 require "livecheck/strategy"
 require "bundle_version"
 
-describe Homebrew::Livecheck::Strategy::ExtractPlist do
+RSpec.describe Homebrew::Livecheck::Strategy::ExtractPlist do
   subject(:extract_plist) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy/git_spec.rb b/Library/Homebrew/test/livecheck/strategy/git_spec.rb
index 901cea21a4..1afcd9c786 100644
--- a/Library/Homebrew/test/livecheck/strategy/git_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/git_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Git do
+RSpec.describe Homebrew::Livecheck::Strategy::Git do
   subject(:git) { described_class }
 
   let(:git_url) { "https://github.com/Homebrew/brew.git" }
diff --git a/Library/Homebrew/test/livecheck/strategy/github_latest_spec.rb b/Library/Homebrew/test/livecheck/strategy/github_latest_spec.rb
index f118e11407..0a14f238de 100644
--- a/Library/Homebrew/test/livecheck/strategy/github_latest_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/github_latest_spec.rb
@@ -3,7 +3,7 @@
 require "livecheck/strategy/github_releases"
 require "livecheck/strategy/github_latest"
 
-describe Homebrew::Livecheck::Strategy::GithubLatest do
+RSpec.describe Homebrew::Livecheck::Strategy::GithubLatest do
   subject(:github_latest) { described_class }
 
   let(:github_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/github_releases_spec.rb b/Library/Homebrew/test/livecheck/strategy/github_releases_spec.rb
index 597472509f..d9dd1897a4 100644
--- a/Library/Homebrew/test/livecheck/strategy/github_releases_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/github_releases_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::GithubReleases do
+RSpec.describe Homebrew::Livecheck::Strategy::GithubReleases do
   subject(:github_releases) { described_class }
 
   let(:github_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/gnome_spec.rb b/Library/Homebrew/test/livecheck/strategy/gnome_spec.rb
index 1062e1f6fd..d88d11fd24 100644
--- a/Library/Homebrew/test/livecheck/strategy/gnome_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/gnome_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/gnome"
 
-describe Homebrew::Livecheck::Strategy::Gnome do
+RSpec.describe Homebrew::Livecheck::Strategy::Gnome do
   subject(:gnome) { described_class }
 
   let(:gnome_url) { "https://download.gnome.org/sources/abc/1.2/abc-1.2.3.tar.xz" }
diff --git a/Library/Homebrew/test/livecheck/strategy/gnu_spec.rb b/Library/Homebrew/test/livecheck/strategy/gnu_spec.rb
index 482e6c10b9..32c8037041 100644
--- a/Library/Homebrew/test/livecheck/strategy/gnu_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/gnu_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/gnu"
 
-describe Homebrew::Livecheck::Strategy::Gnu do
+RSpec.describe Homebrew::Livecheck::Strategy::Gnu do
   subject(:gnu) { described_class }
 
   let(:gnu_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/hackage_spec.rb b/Library/Homebrew/test/livecheck/strategy/hackage_spec.rb
index 8535107198..df859034bd 100644
--- a/Library/Homebrew/test/livecheck/strategy/hackage_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/hackage_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/hackage"
 
-describe Homebrew::Livecheck::Strategy::Hackage do
+RSpec.describe Homebrew::Livecheck::Strategy::Hackage do
   subject(:hackage) { described_class }
 
   let(:hackage_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/header_match_spec.rb b/Library/Homebrew/test/livecheck/strategy/header_match_spec.rb
index d48813b6b2..d7baece1eb 100644
--- a/Library/Homebrew/test/livecheck/strategy/header_match_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/header_match_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::HeaderMatch do
+RSpec.describe Homebrew::Livecheck::Strategy::HeaderMatch do
   subject(:header_match) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy/json_spec.rb b/Library/Homebrew/test/livecheck/strategy/json_spec.rb
index f92c74afa8..dadaab33db 100644
--- a/Library/Homebrew/test/livecheck/strategy/json_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/json_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Json do
+RSpec.describe Homebrew::Livecheck::Strategy::Json do
   subject(:json) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy/launchpad_spec.rb b/Library/Homebrew/test/livecheck/strategy/launchpad_spec.rb
index 4ae1bfb2ec..f1f6121753 100644
--- a/Library/Homebrew/test/livecheck/strategy/launchpad_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/launchpad_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/launchpad"
 
-describe Homebrew::Livecheck::Strategy::Launchpad do
+RSpec.describe Homebrew::Livecheck::Strategy::Launchpad do
   subject(:launchpad) { described_class }
 
   let(:launchpad_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/npm_spec.rb b/Library/Homebrew/test/livecheck/strategy/npm_spec.rb
index 5267b0bddc..2757070629 100644
--- a/Library/Homebrew/test/livecheck/strategy/npm_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/npm_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/npm"
 
-describe Homebrew::Livecheck::Strategy::Npm do
+RSpec.describe Homebrew::Livecheck::Strategy::Npm do
   subject(:npm) { described_class }
 
   let(:npm_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/page_match_spec.rb b/Library/Homebrew/test/livecheck/strategy/page_match_spec.rb
index a5f43f14f8..3ffd22d5e2 100644
--- a/Library/Homebrew/test/livecheck/strategy/page_match_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/page_match_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::PageMatch do
+RSpec.describe Homebrew::Livecheck::Strategy::PageMatch do
   subject(:page_match) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy/pypi_spec.rb b/Library/Homebrew/test/livecheck/strategy/pypi_spec.rb
index a0bba3a8df..eb568aeecf 100644
--- a/Library/Homebrew/test/livecheck/strategy/pypi_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/pypi_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Pypi do
+RSpec.describe Homebrew::Livecheck::Strategy::Pypi do
   subject(:pypi) { described_class }
 
   let(:pypi_url) { "https://files.pythonhosted.org/packages/ab/cd/efg/example-1.2.3.tar.gz" }
diff --git a/Library/Homebrew/test/livecheck/strategy/sourceforge_spec.rb b/Library/Homebrew/test/livecheck/strategy/sourceforge_spec.rb
index 5940cd9818..43f51df67e 100644
--- a/Library/Homebrew/test/livecheck/strategy/sourceforge_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/sourceforge_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/sourceforge"
 
-describe Homebrew::Livecheck::Strategy::Sourceforge do
+RSpec.describe Homebrew::Livecheck::Strategy::Sourceforge do
   subject(:sourceforge) { described_class }
 
   let(:sourceforge_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/sparkle_spec.rb b/Library/Homebrew/test/livecheck/strategy/sparkle_spec.rb
index 86a890151b..3e7eff78d3 100644
--- a/Library/Homebrew/test/livecheck/strategy/sparkle_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/sparkle_spec.rb
@@ -3,7 +3,7 @@
 require "livecheck/strategy"
 require "bundle_version"
 
-describe Homebrew::Livecheck::Strategy::Sparkle do
+RSpec.describe Homebrew::Livecheck::Strategy::Sparkle do
   subject(:sparkle) { described_class }
 
   def create_appcast_xml(items_str = "")
diff --git a/Library/Homebrew/test/livecheck/strategy/xml_spec.rb b/Library/Homebrew/test/livecheck/strategy/xml_spec.rb
index 5794ae40f1..9ab0d13ff4 100644
--- a/Library/Homebrew/test/livecheck/strategy/xml_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/xml_spec.rb
@@ -3,7 +3,7 @@
 require "livecheck/strategy"
 require "rexml/document"
 
-describe Homebrew::Livecheck::Strategy::Xml do
+RSpec.describe Homebrew::Livecheck::Strategy::Xml do
   subject(:xml) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy/xorg_spec.rb b/Library/Homebrew/test/livecheck/strategy/xorg_spec.rb
index 45cf73a28a..230f632938 100644
--- a/Library/Homebrew/test/livecheck/strategy/xorg_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/xorg_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy/xorg"
 
-describe Homebrew::Livecheck::Strategy::Xorg do
+RSpec.describe Homebrew::Livecheck::Strategy::Xorg do
   subject(:xorg) { described_class }
 
   let(:xorg_urls) do
diff --git a/Library/Homebrew/test/livecheck/strategy/yaml_spec.rb b/Library/Homebrew/test/livecheck/strategy/yaml_spec.rb
index 40cb994838..835abb2b8d 100644
--- a/Library/Homebrew/test/livecheck/strategy/yaml_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy/yaml_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy::Yaml do
+RSpec.describe Homebrew::Livecheck::Strategy::Yaml do
   subject(:yaml) { described_class }
 
   let(:http_url) { "https://brew.sh/blog/" }
diff --git a/Library/Homebrew/test/livecheck/strategy_spec.rb b/Library/Homebrew/test/livecheck/strategy_spec.rb
index 7721757798..7ed67125bd 100644
--- a/Library/Homebrew/test/livecheck/strategy_spec.rb
+++ b/Library/Homebrew/test/livecheck/strategy_spec.rb
@@ -2,7 +2,7 @@
 
 require "livecheck/strategy"
 
-describe Homebrew::Livecheck::Strategy do
+RSpec.describe Homebrew::Livecheck::Strategy do
   subject(:strategy) { described_class }
 
   describe "::from_symbol" do
diff --git a/Library/Homebrew/test/livecheck_spec.rb b/Library/Homebrew/test/livecheck_spec.rb
index b7c3cd49db..a3fd7e6dd4 100644
--- a/Library/Homebrew/test/livecheck_spec.rb
+++ b/Library/Homebrew/test/livecheck_spec.rb
@@ -3,7 +3,7 @@
 require "formula"
 require "livecheck"
 
-describe Livecheck do
+RSpec.describe Livecheck do
   let(:f) do
     formula do
       homepage "https://brew.sh"
diff --git a/Library/Homebrew/test/locale_spec.rb b/Library/Homebrew/test/locale_spec.rb
index fea66e26b1..c0d3564d73 100644
--- a/Library/Homebrew/test/locale_spec.rb
+++ b/Library/Homebrew/test/locale_spec.rb
@@ -2,7 +2,7 @@
 
 require "locale"
 
-describe Locale do
+RSpec.describe Locale do
   describe "::parse" do
     it "parses a string in the correct format" do
       expect(described_class.parse("zh")).to eql(described_class.new("zh", nil, nil))
diff --git a/Library/Homebrew/test/lock_file_spec.rb b/Library/Homebrew/test/lock_file_spec.rb
index 08881fd38d..a71dc2403e 100644
--- a/Library/Homebrew/test/lock_file_spec.rb
+++ b/Library/Homebrew/test/lock_file_spec.rb
@@ -2,7 +2,7 @@
 
 require "lock_file"
 
-describe LockFile do
+RSpec.describe LockFile do
   subject(:lock_file) { described_class.new("foo") }
 
   describe "#lock" do
diff --git a/Library/Homebrew/test/macos_runner_spec_spec.rb b/Library/Homebrew/test/macos_runner_spec_spec.rb
index e676434d58..9f881787ce 100644
--- a/Library/Homebrew/test/macos_runner_spec_spec.rb
+++ b/Library/Homebrew/test/macos_runner_spec_spec.rb
@@ -2,7 +2,7 @@
 
 require "macos_runner_spec"
 
-describe MacOSRunnerSpec do
+RSpec.describe MacOSRunnerSpec do
   let(:spec) { described_class.new(name: "macOS 11-arm64", runner: "11-arm64", timeout: 90, cleanup: true) }
 
   it "has immutable attributes" do
diff --git a/Library/Homebrew/test/macos_version_spec.rb b/Library/Homebrew/test/macos_version_spec.rb
index 61e248dfd0..e4de970bd5 100644
--- a/Library/Homebrew/test/macos_version_spec.rb
+++ b/Library/Homebrew/test/macos_version_spec.rb
@@ -2,7 +2,7 @@
 
 require "macos_version"
 
-describe MacOSVersion do
+RSpec.describe MacOSVersion do
   let(:version) { described_class.new("10.14") }
   let(:big_sur_major) { described_class.new("11.0") }
   let(:big_sur_update) { described_class.new("11.1") }
diff --git a/Library/Homebrew/test/messages_spec.rb b/Library/Homebrew/test/messages_spec.rb
index 390883c6a2..ca37a44535 100644
--- a/Library/Homebrew/test/messages_spec.rb
+++ b/Library/Homebrew/test/messages_spec.rb
@@ -3,7 +3,7 @@
 require "messages"
 require "spec_helper"
 
-describe Messages do
+RSpec.describe Messages do
   let(:messages) { described_class.new }
   let(:test_formula) { formula("foo") { url("https://brew.sh/foo-0.1.tgz") } }
   let(:elapsed_time) { 1.1 }
diff --git a/Library/Homebrew/test/migrator_spec.rb b/Library/Homebrew/test/migrator_spec.rb
index 0fbc19c106..87fadd5e95 100644
--- a/Library/Homebrew/test/migrator_spec.rb
+++ b/Library/Homebrew/test/migrator_spec.rb
@@ -5,7 +5,7 @@ require "test/support/fixtures/testball"
 require "tab"
 require "keg"
 
-describe Migrator do
+RSpec.describe Migrator do
   subject(:migrator) { described_class.new(new_formula, old_formula.name) }
 
   let(:new_formula) { Testball.new("newname") }
diff --git a/Library/Homebrew/test/missing_formula_spec.rb b/Library/Homebrew/test/missing_formula_spec.rb
index 3c379ddcbc..8c69381af5 100644
--- a/Library/Homebrew/test/missing_formula_spec.rb
+++ b/Library/Homebrew/test/missing_formula_spec.rb
@@ -2,7 +2,7 @@
 
 require "missing_formula"
 
-describe Homebrew::MissingFormula do
+RSpec.describe Homebrew::MissingFormula do
   describe "::reason" do
     subject { described_class.reason("gem") }
 
diff --git a/Library/Homebrew/test/options/deprecated_option_spec.rb b/Library/Homebrew/test/options/deprecated_option_spec.rb
index 4915e3bfdd..9ee7c02771 100644
--- a/Library/Homebrew/test/options/deprecated_option_spec.rb
+++ b/Library/Homebrew/test/options/deprecated_option_spec.rb
@@ -2,7 +2,7 @@
 
 require "options"
 
-describe DeprecatedOption do
+RSpec.describe DeprecatedOption do
   subject(:option) { described_class.new("foo", "bar") }
 
   specify "#old" do
diff --git a/Library/Homebrew/test/options/option_spec.rb b/Library/Homebrew/test/options/option_spec.rb
index ce35690415..692483d526 100644
--- a/Library/Homebrew/test/options/option_spec.rb
+++ b/Library/Homebrew/test/options/option_spec.rb
@@ -2,7 +2,7 @@
 
 require "options"
 
-describe Option do
+RSpec.describe Option do
   subject(:option) { described_class.new("foo") }
 
   specify "#to_s" do
diff --git a/Library/Homebrew/test/options_spec.rb b/Library/Homebrew/test/options_spec.rb
index 3138e05456..8969d6de5a 100644
--- a/Library/Homebrew/test/options_spec.rb
+++ b/Library/Homebrew/test/options_spec.rb
@@ -2,7 +2,7 @@
 
 require "options"
 
-describe Options do
+RSpec.describe Options do
   subject(:options) { described_class.new }
 
   it "removes duplicate options" do
diff --git a/Library/Homebrew/test/os/linux/dependency_collector_spec.rb b/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
index 15a149abe4..3ba82de27a 100644
--- a/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/os/linux/dependency_collector_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependency_collector"
 
-describe DependencyCollector do
+RSpec.describe DependencyCollector do
   alias_matcher :be_a_build_requirement, :be_build
 
   subject(:collector) { described_class.new }
diff --git a/Library/Homebrew/test/os/linux/diagnostic_spec.rb b/Library/Homebrew/test/os/linux/diagnostic_spec.rb
index 076604fb3b..4a1d23169c 100644
--- a/Library/Homebrew/test/os/linux/diagnostic_spec.rb
+++ b/Library/Homebrew/test/os/linux/diagnostic_spec.rb
@@ -2,7 +2,7 @@
 
 require "diagnostic"
 
-describe Homebrew::Diagnostic::Checks do
+RSpec.describe Homebrew::Diagnostic::Checks do
   subject(:checks) { described_class.new }
 
   specify "#check_supported_architecture" do
diff --git a/Library/Homebrew/test/os/linux/formula_spec.rb b/Library/Homebrew/test/os/linux/formula_spec.rb
index 3b85a88400..0149343376 100644
--- a/Library/Homebrew/test/os/linux/formula_spec.rb
+++ b/Library/Homebrew/test/os/linux/formula_spec.rb
@@ -3,7 +3,7 @@
 require "test/support/fixtures/testball"
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   describe "#uses_from_macos" do
     before do
       allow(OS).to receive(:mac?).and_return(false)
diff --git a/Library/Homebrew/test/os/linux/pathname_spec.rb b/Library/Homebrew/test/os/linux/pathname_spec.rb
index 7dec7b60dd..de348cd79c 100644
--- a/Library/Homebrew/test/os/linux/pathname_spec.rb
+++ b/Library/Homebrew/test/os/linux/pathname_spec.rb
@@ -2,7 +2,7 @@
 
 require "extend/pathname"
 
-describe Pathname do
+RSpec.describe Pathname do
   let(:elf_dir) { described_class.new "#{TEST_FIXTURE_DIR}/elf" }
   let(:sho) { elf_dir/"libforty.so.0" }
   let(:sho_without_runpath_rpath) { elf_dir/"libhello.so.0" }
diff --git a/Library/Homebrew/test/os/mac/dependency_collector_spec.rb b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
index db369ac998..d4336395a8 100644
--- a/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
+++ b/Library/Homebrew/test/os/mac/dependency_collector_spec.rb
@@ -2,7 +2,7 @@
 
 require "dependency_collector"
 
-describe DependencyCollector do
+RSpec.describe DependencyCollector do
   alias_matcher :need_tar_xz_dependency, :be_tar_needs_xz_dependency
 
   subject(:collector) { described_class.new }
diff --git a/Library/Homebrew/test/os/mac/diagnostic_spec.rb b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
index 17648c0eb4..c75a2da2a4 100644
--- a/Library/Homebrew/test/os/mac/diagnostic_spec.rb
+++ b/Library/Homebrew/test/os/mac/diagnostic_spec.rb
@@ -2,7 +2,7 @@
 
 require "diagnostic"
 
-describe Homebrew::Diagnostic::Checks do
+RSpec.describe Homebrew::Diagnostic::Checks do
   subject(:checks) { described_class.new }
 
   specify "#check_for_unsupported_macos" do
diff --git a/Library/Homebrew/test/os/mac/formula_spec.rb b/Library/Homebrew/test/os/mac/formula_spec.rb
index 1a2344ff25..0a242912be 100644
--- a/Library/Homebrew/test/os/mac/formula_spec.rb
+++ b/Library/Homebrew/test/os/mac/formula_spec.rb
@@ -3,7 +3,7 @@
 require "test/support/fixtures/testball"
 require "formula"
 
-describe Formula do
+RSpec.describe Formula do
   describe "#uses_from_macos" do
     before do
       allow(OS).to receive(:mac?).and_return(true)
diff --git a/Library/Homebrew/test/os/mac/keg_spec.rb b/Library/Homebrew/test/os/mac/keg_spec.rb
index cb577f76ab..b87beb5d4a 100644
--- a/Library/Homebrew/test/os/mac/keg_spec.rb
+++ b/Library/Homebrew/test/os/mac/keg_spec.rb
@@ -2,7 +2,7 @@
 
 require "keg"
 
-describe Keg do
+RSpec.describe Keg do
   include FileUtils
 
   subject(:keg) { described_class.new(keg_path) }
diff --git a/Library/Homebrew/test/os/mac/mach_spec.rb b/Library/Homebrew/test/os/mac/mach_spec.rb
index f33db3d78d..4f6da3938f 100644
--- a/Library/Homebrew/test/os/mac/mach_spec.rb
+++ b/Library/Homebrew/test/os/mac/mach_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe "Mach-O" do
+RSpec.describe "Mach-O" do
   describe "Pathname tests" do
     specify "fat dylib" do
       pn = dylib_path("fat")
diff --git a/Library/Homebrew/test/os/mac/pkgconfig_spec.rb b/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
index c3ad3f3ec3..849c17b332 100644
--- a/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
+++ b/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
@@ -12,7 +12,7 @@
 # Additionally, libffi version detection cannot be performed on systems running Mojave or earlier.
 #
 # For indeterminable cases, consult https://opensource.apple.com for the version used.
-describe "pkg-config", :needs_ci do
+RSpec.describe "pkg-config", :needs_ci do
   def pc_version(library)
     path = HOMEBREW_LIBRARY_PATH/"os/mac/pkgconfig/#{MacOS.version}/#{library}.pc"
     version = File.foreach(path)
diff --git a/Library/Homebrew/test/os/mac/sdk_spec.rb b/Library/Homebrew/test/os/mac/sdk_spec.rb
index fd9b5e9ac0..cc039aa729 100644
--- a/Library/Homebrew/test/os/mac/sdk_spec.rb
+++ b/Library/Homebrew/test/os/mac/sdk_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe OS::Mac::CLTSDKLocator do
+RSpec.describe OS::Mac::CLTSDKLocator do
   subject(:locator) { described_class.new }
 
   let(:big_sur_sdk) { OS::Mac::SDK.new(MacOSVersion.new("11"), "/some/path/MacOSX.sdk", :clt) }
diff --git a/Library/Homebrew/test/os/mac_spec.rb b/Library/Homebrew/test/os/mac_spec.rb
index 8ec93eb75d..e2bc5eab37 100644
--- a/Library/Homebrew/test/os/mac_spec.rb
+++ b/Library/Homebrew/test/os/mac_spec.rb
@@ -3,7 +3,7 @@
 require "locale"
 require "os/mac"
 
-describe OS::Mac do
+RSpec.describe OS::Mac do
   describe "::languages" do
     it "returns a list of all languages" do
       expect(described_class.languages).not_to be_empty
diff --git a/Library/Homebrew/test/os/os_spec.rb b/Library/Homebrew/test/os/os_spec.rb
index 7dae2be4ce..0dd0463bf7 100644
--- a/Library/Homebrew/test/os/os_spec.rb
+++ b/Library/Homebrew/test/os/os_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe OS do
+RSpec.describe OS do
   describe "::kernel_version" do
     it "is not NULL" do
       expect(described_class.kernel_version).not_to be_null
diff --git a/Library/Homebrew/test/patch_spec.rb b/Library/Homebrew/test/patch_spec.rb
index bb62001488..7b3ca093e9 100644
--- a/Library/Homebrew/test/patch_spec.rb
+++ b/Library/Homebrew/test/patch_spec.rb
@@ -2,7 +2,7 @@
 
 require "patch"
 
-describe Patch do
+RSpec.describe Patch do
   describe "#create" do
     context "with a simple patch" do
       subject { described_class.create(:p2, nil) }
diff --git a/Library/Homebrew/test/patching_spec.rb b/Library/Homebrew/test/patching_spec.rb
index 050d1f7a19..bf1be10b9d 100644
--- a/Library/Homebrew/test/patching_spec.rb
+++ b/Library/Homebrew/test/patching_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula"
 
-describe "patching" do
+RSpec.describe "patching" do
   let(:formula_subclass) do
     Class.new(Formula) do
       # These are defined within an anonymous class to avoid polluting the global namespace.
diff --git a/Library/Homebrew/test/pathname_spec.rb b/Library/Homebrew/test/pathname_spec.rb
index 0e587068db..b6e7b64b9f 100644
--- a/Library/Homebrew/test/pathname_spec.rb
+++ b/Library/Homebrew/test/pathname_spec.rb
@@ -3,7 +3,7 @@
 require "extend/pathname"
 require "install_renamed"
 
-describe Pathname do
+RSpec.describe Pathname do
   include FileUtils
 
   let(:src) { mktmpdir }
diff --git a/Library/Homebrew/test/pkg_version_spec.rb b/Library/Homebrew/test/pkg_version_spec.rb
index 6f066cb9fc..578ae2a14f 100644
--- a/Library/Homebrew/test/pkg_version_spec.rb
+++ b/Library/Homebrew/test/pkg_version_spec.rb
@@ -2,7 +2,7 @@
 
 require "pkg_version"
 
-describe PkgVersion do
+RSpec.describe PkgVersion do
   describe "::parse" do
     it "parses versions from a string" do
       expect(described_class.parse("1.0_1")).to eq(described_class.new(Version.new("1.0"), 1))
diff --git a/Library/Homebrew/test/requirement_spec.rb b/Library/Homebrew/test/requirement_spec.rb
index eb676810f2..7b578004ed 100644
--- a/Library/Homebrew/test/requirement_spec.rb
+++ b/Library/Homebrew/test/requirement_spec.rb
@@ -3,7 +3,7 @@
 require "extend/ENV"
 require "requirement"
 
-describe Requirement do
+RSpec.describe Requirement do
   alias_matcher :be_a_build_requirement, :be_a_build
 
   subject(:requirement) { klass.new }
diff --git a/Library/Homebrew/test/requirements/arch_requirement_spec.rb b/Library/Homebrew/test/requirements/arch_requirement_spec.rb
index 1dcbbf87a4..bb0480a2a3 100644
--- a/Library/Homebrew/test/requirements/arch_requirement_spec.rb
+++ b/Library/Homebrew/test/requirements/arch_requirement_spec.rb
@@ -2,7 +2,7 @@
 
 require "requirements/arch_requirement"
 
-describe ArchRequirement do
+RSpec.describe ArchRequirement do
   subject(:requirement) { described_class.new([Hardware::CPU.type]) }
 
   describe "#satisfied?" do
diff --git a/Library/Homebrew/test/requirements/codesign_requirement_spec.rb b/Library/Homebrew/test/requirements/codesign_requirement_spec.rb
index 02da1bff60..7f4c1b2586 100644
--- a/Library/Homebrew/test/requirements/codesign_requirement_spec.rb
+++ b/Library/Homebrew/test/requirements/codesign_requirement_spec.rb
@@ -2,7 +2,7 @@
 
 require "requirements/codesign_requirement"
 
-describe CodesignRequirement do
+RSpec.describe CodesignRequirement do
   subject(:requirement) do
     described_class.new([{ identity: identity, with: with, url: url }])
   end
diff --git a/Library/Homebrew/test/requirements/linux_requirement_spec.rb b/Library/Homebrew/test/requirements/linux_requirement_spec.rb
index cb8d3a34d5..ce67fd6e57 100644
--- a/Library/Homebrew/test/requirements/linux_requirement_spec.rb
+++ b/Library/Homebrew/test/requirements/linux_requirement_spec.rb
@@ -2,7 +2,7 @@
 
 require "requirements/linux_requirement"
 
-describe LinuxRequirement do
+RSpec.describe LinuxRequirement do
   subject(:requirement) { described_class.new }
 
   describe "#satisfied?" do
diff --git a/Library/Homebrew/test/requirements/macos_requirement_spec.rb b/Library/Homebrew/test/requirements/macos_requirement_spec.rb
index c4dc2affbf..5d81012193 100644
--- a/Library/Homebrew/test/requirements/macos_requirement_spec.rb
+++ b/Library/Homebrew/test/requirements/macos_requirement_spec.rb
@@ -2,7 +2,7 @@
 
 require "requirements/macos_requirement"
 
-describe MacOSRequirement do
+RSpec.describe MacOSRequirement do
   subject(:requirement) { described_class.new }
 
   describe "#satisfied?" do
diff --git a/Library/Homebrew/test/requirements_spec.rb b/Library/Homebrew/test/requirements_spec.rb
index 6002eea055..f7c6eca536 100644
--- a/Library/Homebrew/test/requirements_spec.rb
+++ b/Library/Homebrew/test/requirements_spec.rb
@@ -2,7 +2,7 @@
 
 require "requirements"
 
-describe Requirements do
+RSpec.describe Requirements do
   subject(:requirements) { described_class.new }
 
   describe "#<<" do
diff --git a/Library/Homebrew/test/resource_spec.rb b/Library/Homebrew/test/resource_spec.rb
index 57be3a9fd2..e509902bde 100644
--- a/Library/Homebrew/test/resource_spec.rb
+++ b/Library/Homebrew/test/resource_spec.rb
@@ -3,7 +3,7 @@
 require "resource"
 require "livecheck"
 
-describe Resource do
+RSpec.describe Resource do
   subject(:resource) { described_class.new("test") }
 
   let(:livecheck_resource) do
diff --git a/Library/Homebrew/test/rubocop_spec.rb b/Library/Homebrew/test/rubocop_spec.rb
index ce163c2d98..7c49fc9df1 100644
--- a/Library/Homebrew/test/rubocop_spec.rb
+++ b/Library/Homebrew/test/rubocop_spec.rb
@@ -2,7 +2,7 @@
 
 require "open3"
 
-describe "RuboCop" do
+RSpec.describe "RuboCop" do
   context "when calling `rubocop` outside of the Homebrew environment" do
     before do
       ENV.each_key do |key|
diff --git a/Library/Homebrew/test/rubocops/blank_spec.rb b/Library/Homebrew/test/rubocops/blank_spec.rb
index 4b71576137..78504cd4d7 100644
--- a/Library/Homebrew/test/rubocops/blank_spec.rb
+++ b/Library/Homebrew/test/rubocops/blank_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/blank"
 
-describe RuboCop::Cop::Homebrew::Blank, :config do
+RSpec.describe RuboCop::Cop::Homebrew::Blank, :config do
   shared_examples "offense" do |source, correction, message|
     it "registers an offense and corrects" do
       expect_offense(<<~RUBY, source: source, message: message)
diff --git a/Library/Homebrew/test/rubocops/bottle/bottle_digest_indentation_spec.rb b/Library/Homebrew/test/rubocops/bottle/bottle_digest_indentation_spec.rb
index ca080e2a5e..ea116ca670 100644
--- a/Library/Homebrew/test/rubocops/bottle/bottle_digest_indentation_spec.rb
+++ b/Library/Homebrew/test/rubocops/bottle/bottle_digest_indentation_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/bottle"
 
-describe RuboCop::Cop::FormulaAudit::BottleDigestIndentation do
+RSpec.describe RuboCop::Cop::FormulaAudit::BottleDigestIndentation do
   subject(:cop) { described_class.new }
 
   it "reports no offenses for `bottle :unneeded`" do
diff --git a/Library/Homebrew/test/rubocops/bottle/bottle_format_spec.rb b/Library/Homebrew/test/rubocops/bottle/bottle_format_spec.rb
index b76c497029..3f6b4853d1 100644
--- a/Library/Homebrew/test/rubocops/bottle/bottle_format_spec.rb
+++ b/Library/Homebrew/test/rubocops/bottle/bottle_format_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/bottle"
 
-describe RuboCop::Cop::FormulaAudit::BottleFormat do
+RSpec.describe RuboCop::Cop::FormulaAudit::BottleFormat do
   subject(:cop) { described_class.new }
 
   it "reports no offenses for `bottle :unneeded`" do
diff --git a/Library/Homebrew/test/rubocops/bottle/bottle_order_spec.rb b/Library/Homebrew/test/rubocops/bottle/bottle_order_spec.rb
index 2a095c2c0c..94209b7ea9 100644
--- a/Library/Homebrew/test/rubocops/bottle/bottle_order_spec.rb
+++ b/Library/Homebrew/test/rubocops/bottle/bottle_order_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/bottle"
 
-describe RuboCop::Cop::FormulaAudit::BottleOrder do
+RSpec.describe RuboCop::Cop::FormulaAudit::BottleOrder do
   subject(:cop) { described_class.new }
 
   it "reports no offenses for `bottle :unneeded`" do
diff --git a/Library/Homebrew/test/rubocops/bottle/bottle_tag_indentation_spec.rb b/Library/Homebrew/test/rubocops/bottle/bottle_tag_indentation_spec.rb
index 36c264b1f2..8bc13448aa 100644
--- a/Library/Homebrew/test/rubocops/bottle/bottle_tag_indentation_spec.rb
+++ b/Library/Homebrew/test/rubocops/bottle/bottle_tag_indentation_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/bottle"
 
-describe RuboCop::Cop::FormulaAudit::BottleTagIndentation do
+RSpec.describe RuboCop::Cop::FormulaAudit::BottleTagIndentation do
   subject(:cop) { described_class.new }
 
   it "reports no offenses for `bottle :unneeded`" do
diff --git a/Library/Homebrew/test/rubocops/cask/array_alphabetization_spec.rb b/Library/Homebrew/test/rubocops/cask/array_alphabetization_spec.rb
index da981e714b..43d9b9768c 100644
--- a/Library/Homebrew/test/rubocops/cask/array_alphabetization_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/array_alphabetization_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::ArrayAlphabetization, :config do
+RSpec.describe RuboCop::Cop::Cask::ArrayAlphabetization, :config do
   it "reports an offense when a single `zap trash` path is specified in an array" do
     expect_offense(<<~CASK)
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/cask/desc_spec.rb b/Library/Homebrew/test/rubocops/cask/desc_spec.rb
index 0a95919bf5..dc3fe2629a 100644
--- a/Library/Homebrew/test/rubocops/cask/desc_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/desc_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::Desc, :config do
+RSpec.describe RuboCop::Cop::Cask::Desc, :config do
   it "does not start with an article" do
     expect_no_offenses <<~RUBY
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/cask/discontinued_spec.rb b/Library/Homebrew/test/rubocops/cask/discontinued_spec.rb
index e3264600aa..a1b3a82afa 100644
--- a/Library/Homebrew/test/rubocops/cask/discontinued_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/discontinued_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::Discontinued, :config do
+RSpec.describe RuboCop::Cop::Cask::Discontinued, :config do
   it "reports no offenses when there is no `caveats` stanza" do
     expect_no_offenses <<~CASK
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/cask/homepage_url_trailing_slash_spec.rb b/Library/Homebrew/test/rubocops/cask/homepage_url_trailing_slash_spec.rb
index 9cb668817b..a89971b68a 100644
--- a/Library/Homebrew/test/rubocops/cask/homepage_url_trailing_slash_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/homepage_url_trailing_slash_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::HomepageUrlTrailingSlash, :config do
+RSpec.describe RuboCop::Cop::Cask::HomepageUrlTrailingSlash, :config do
   it "accepts a homepage URL ending with a slash" do
     expect_no_offenses <<~CASK
       cask 'foo' do
diff --git a/Library/Homebrew/test/rubocops/cask/no_overrides_spec.rb b/Library/Homebrew/test/rubocops/cask/no_overrides_spec.rb
index fb1bcde025..3b68c05a32 100644
--- a/Library/Homebrew/test/rubocops/cask/no_overrides_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/no_overrides_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::NoOverrides, :config do
+RSpec.describe RuboCop::Cop::Cask::NoOverrides, :config do
   it "accepts when there are no `on_*` blocks" do
     expect_no_offenses <<~CASK
       cask 'foo' do
diff --git a/Library/Homebrew/test/rubocops/cask/on_system_conditionals_spec.rb b/Library/Homebrew/test/rubocops/cask/on_system_conditionals_spec.rb
index 5327ac93c8..7777d226af 100644
--- a/Library/Homebrew/test/rubocops/cask/on_system_conditionals_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/on_system_conditionals_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::OnSystemConditionals, :config do
+RSpec.describe RuboCop::Cop::Cask::OnSystemConditionals, :config do
   context "when auditing `postflight` stanzas" do
     it "accepts when there are no `on_*` blocks" do
       expect_no_offenses <<~CASK
diff --git a/Library/Homebrew/test/rubocops/cask/shared_filelist_glob_spec.rb b/Library/Homebrew/test/rubocops/cask/shared_filelist_glob_spec.rb
index cc375563d3..55151c9f6f 100644
--- a/Library/Homebrew/test/rubocops/cask/shared_filelist_glob_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/shared_filelist_glob_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::SharedFilelistGlob, :config do
+RSpec.describe RuboCop::Cop::Cask::SharedFilelistGlob, :config do
   it "reports an offense when a zap trash array includes an .sfl2 or .sfl3 file" do
     expect_offense(<<~CASK)
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/cask/stanza_grouping_spec.rb b/Library/Homebrew/test/rubocops/cask/stanza_grouping_spec.rb
index c2dee22c98..9cf48bb240 100644
--- a/Library/Homebrew/test/rubocops/cask/stanza_grouping_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/stanza_grouping_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::StanzaGrouping, :config do
+RSpec.describe RuboCop::Cop::Cask::StanzaGrouping, :config do
   it "accepts a sole stanza" do
     expect_no_offenses <<~CASK
       cask 'foo' do
diff --git a/Library/Homebrew/test/rubocops/cask/stanza_order_spec.rb b/Library/Homebrew/test/rubocops/cask/stanza_order_spec.rb
index 3c497675e5..da7ce77168 100644
--- a/Library/Homebrew/test/rubocops/cask/stanza_order_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/stanza_order_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::StanzaOrder, :config do
+RSpec.describe RuboCop::Cop::Cask::StanzaOrder, :config do
   it "accepts a sole stanza" do
     expect_no_offenses <<~CASK
       cask 'foo' do
diff --git a/Library/Homebrew/test/rubocops/cask/uninstall_methods_order_spec.rb b/Library/Homebrew/test/rubocops/cask/uninstall_methods_order_spec.rb
index c44e31e365..6ebf72c0ef 100644
--- a/Library/Homebrew/test/rubocops/cask/uninstall_methods_order_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/uninstall_methods_order_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 require "rubocops/rubocop-cask"
-describe RuboCop::Cop::Cask::UninstallMethodsOrder, :config do
+RSpec.describe RuboCop::Cop::Cask::UninstallMethodsOrder, :config do
   context "with uninstall blocks" do
     context "when methods are incorrectly ordered" do
       it "detects and corrects ordering offenses in the uninstall block when each method contains a single item" do
diff --git a/Library/Homebrew/test/rubocops/cask/url_legacy_comma_separators_spec.rb b/Library/Homebrew/test/rubocops/cask/url_legacy_comma_separators_spec.rb
index 5b9489f48c..1fe0e63c3b 100644
--- a/Library/Homebrew/test/rubocops/cask/url_legacy_comma_separators_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/url_legacy_comma_separators_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::UrlLegacyCommaSeparators, :config do
+RSpec.describe RuboCop::Cop::Cask::UrlLegacyCommaSeparators, :config do
   it "accepts a simple `version` interpolation" do
     expect_no_offenses <<~'CASK'
       cask 'foo' do
diff --git a/Library/Homebrew/test/rubocops/cask/url_spec.rb b/Library/Homebrew/test/rubocops/cask/url_spec.rb
index a541434382..e984d82cb0 100644
--- a/Library/Homebrew/test/rubocops/cask/url_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/url_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::Url, :config do
+RSpec.describe RuboCop::Cop::Cask::Url, :config do
   it "accepts a `verified` value that does not start with a protocol" do
     expect_no_offenses <<~CASK
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/cask/variables_spec.rb b/Library/Homebrew/test/rubocops/cask/variables_spec.rb
index 25229c6d6c..b597a584ee 100644
--- a/Library/Homebrew/test/rubocops/cask/variables_spec.rb
+++ b/Library/Homebrew/test/rubocops/cask/variables_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/rubocop-cask"
 
-describe RuboCop::Cop::Cask::Variables, :config do
+RSpec.describe RuboCop::Cop::Cask::Variables, :config do
   it "accepts when there are no variables" do
     expect_no_offenses <<~CASK
       cask "foo" do
diff --git a/Library/Homebrew/test/rubocops/caveats_spec.rb b/Library/Homebrew/test/rubocops/caveats_spec.rb
index ceed20bfa3..04cc4b35d6 100644
--- a/Library/Homebrew/test/rubocops/caveats_spec.rb
+++ b/Library/Homebrew/test/rubocops/caveats_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/caveats"
 
-describe RuboCop::Cop::FormulaAudit::Caveats do
+RSpec.describe RuboCop::Cop::FormulaAudit::Caveats do
   subject(:cop) { described_class.new }
 
   context "when auditing `caveats`" do
diff --git a/Library/Homebrew/test/rubocops/checksum/checksum_case_spec.rb b/Library/Homebrew/test/rubocops/checksum/checksum_case_spec.rb
index d2905f3de5..c05e29827d 100644
--- a/Library/Homebrew/test/rubocops/checksum/checksum_case_spec.rb
+++ b/Library/Homebrew/test/rubocops/checksum/checksum_case_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/checksum"
 
-describe RuboCop::Cop::FormulaAudit::ChecksumCase do
+RSpec.describe RuboCop::Cop::FormulaAudit::ChecksumCase do
   subject(:cop) { described_class.new }
 
   context "when auditing spec checksums" do
diff --git a/Library/Homebrew/test/rubocops/checksum/checksum_spec.rb b/Library/Homebrew/test/rubocops/checksum/checksum_spec.rb
index 4b9f65c680..a50b7122a7 100644
--- a/Library/Homebrew/test/rubocops/checksum/checksum_spec.rb
+++ b/Library/Homebrew/test/rubocops/checksum/checksum_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/checksum"
 
-describe RuboCop::Cop::FormulaAudit::Checksum do
+RSpec.describe RuboCop::Cop::FormulaAudit::Checksum do
   subject(:cop) { described_class.new }
 
   context "when auditing spec checksums" do
diff --git a/Library/Homebrew/test/rubocops/class/class_name_spec.rb b/Library/Homebrew/test/rubocops/class/class_name_spec.rb
index b280107898..78050236a1 100644
--- a/Library/Homebrew/test/rubocops/class/class_name_spec.rb
+++ b/Library/Homebrew/test/rubocops/class/class_name_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/class"
 
-describe RuboCop::Cop::FormulaAudit::ClassName do
+RSpec.describe RuboCop::Cop::FormulaAudit::ClassName do
   subject(:cop) { described_class.new }
 
   corrected_source = <<~RUBY
diff --git a/Library/Homebrew/test/rubocops/class/test_present.rb b/Library/Homebrew/test/rubocops/class/test_present.rb
index ad3e1b7601..04f5b6c92a 100644
--- a/Library/Homebrew/test/rubocops/class/test_present.rb
+++ b/Library/Homebrew/test/rubocops/class/test_present.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/class"
 
-describe RuboCop::Cop::FormulaAuditStrict::TestPresent do
+RSpec.describe RuboCop::Cop::FormulaAuditStrict::TestPresent do
   subject(:cop) { described_class.new }
 
   it "reports an offense when there is no test block" do
diff --git a/Library/Homebrew/test/rubocops/class/test_spec.rb b/Library/Homebrew/test/rubocops/class/test_spec.rb
index 1d16648f1c..cabeddb71e 100644
--- a/Library/Homebrew/test/rubocops/class/test_spec.rb
+++ b/Library/Homebrew/test/rubocops/class/test_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/class"
 
-describe RuboCop::Cop::FormulaAudit::Test do
+RSpec.describe RuboCop::Cop::FormulaAudit::Test do
   subject(:cop) { described_class.new }
 
   it "reports and corrects an offense when /usr/local/bin is found in test calls" do
diff --git a/Library/Homebrew/test/rubocops/components_order_spec.rb b/Library/Homebrew/test/rubocops/components_order_spec.rb
index b09bd88cf4..8fce98e573 100644
--- a/Library/Homebrew/test/rubocops/components_order_spec.rb
+++ b/Library/Homebrew/test/rubocops/components_order_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/components_order"
 
-describe RuboCop::Cop::FormulaAudit::ComponentsOrder do
+RSpec.describe RuboCop::Cop::FormulaAudit::ComponentsOrder do
   subject(:cop) { described_class.new }
 
   context "when auditing formula components order" do
diff --git a/Library/Homebrew/test/rubocops/components_redundancy_spec.rb b/Library/Homebrew/test/rubocops/components_redundancy_spec.rb
index 4c47722ec3..e65e31ae80 100644
--- a/Library/Homebrew/test/rubocops/components_redundancy_spec.rb
+++ b/Library/Homebrew/test/rubocops/components_redundancy_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/components_redundancy"
 
-describe RuboCop::Cop::FormulaAudit::ComponentsRedundancy do
+RSpec.describe RuboCop::Cop::FormulaAudit::ComponentsRedundancy do
   subject(:cop) { described_class.new }
 
   context "when auditing formula components" do
diff --git a/Library/Homebrew/test/rubocops/conflicts_spec.rb b/Library/Homebrew/test/rubocops/conflicts_spec.rb
index 7dcc422e1e..21967136db 100644
--- a/Library/Homebrew/test/rubocops/conflicts_spec.rb
+++ b/Library/Homebrew/test/rubocops/conflicts_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/conflicts"
 
-describe RuboCop::Cop::FormulaAudit::Conflicts do
+RSpec.describe RuboCop::Cop::FormulaAudit::Conflicts do
   subject(:cop) { described_class.new }
 
   context "when auditing `conflicts_with`" do
diff --git a/Library/Homebrew/test/rubocops/dependency_order_spec.rb b/Library/Homebrew/test/rubocops/dependency_order_spec.rb
index 2c6a05a490..bbcfe253e4 100644
--- a/Library/Homebrew/test/rubocops/dependency_order_spec.rb
+++ b/Library/Homebrew/test/rubocops/dependency_order_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/dependency_order"
 
-describe RuboCop::Cop::FormulaAudit::DependencyOrder do
+RSpec.describe RuboCop::Cop::FormulaAudit::DependencyOrder do
   subject(:cop) { described_class.new }
 
   context "when auditing `uses_from_macos`" do
diff --git a/Library/Homebrew/test/rubocops/deprecate_disable/date_spec.rb b/Library/Homebrew/test/rubocops/deprecate_disable/date_spec.rb
index 4293d4d04e..d613f0a733 100644
--- a/Library/Homebrew/test/rubocops/deprecate_disable/date_spec.rb
+++ b/Library/Homebrew/test/rubocops/deprecate_disable/date_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/deprecate_disable"
 
-describe RuboCop::Cop::FormulaAudit::DeprecateDisableDate do
+RSpec.describe RuboCop::Cop::FormulaAudit::DeprecateDisableDate do
   subject(:cop) { described_class.new }
 
   context "when auditing `deprecate!`" do
diff --git a/Library/Homebrew/test/rubocops/deprecate_disable/reason_spec.rb b/Library/Homebrew/test/rubocops/deprecate_disable/reason_spec.rb
index 4ca2b73ff2..067c8c4bed 100644
--- a/Library/Homebrew/test/rubocops/deprecate_disable/reason_spec.rb
+++ b/Library/Homebrew/test/rubocops/deprecate_disable/reason_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/deprecate_disable"
 
-describe RuboCop::Cop::FormulaAudit::DeprecateDisableReason do
+RSpec.describe RuboCop::Cop::FormulaAudit::DeprecateDisableReason do
   subject(:cop) { described_class.new }
 
   context "when auditing `deprecate!`" do
diff --git a/Library/Homebrew/test/rubocops/desc_spec.rb b/Library/Homebrew/test/rubocops/desc_spec.rb
index e5aa86d90b..29ecf06de7 100644
--- a/Library/Homebrew/test/rubocops/desc_spec.rb
+++ b/Library/Homebrew/test/rubocops/desc_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/desc"
 
-describe RuboCop::Cop::FormulaAudit::Desc do
+RSpec.describe RuboCop::Cop::FormulaAudit::Desc do
   subject(:cop) { described_class.new }
 
   context "when auditing formula `desc` methods" do
diff --git a/Library/Homebrew/test/rubocops/files_spec.rb b/Library/Homebrew/test/rubocops/files_spec.rb
index 49eea3fddf..52071477fa 100644
--- a/Library/Homebrew/test/rubocops/files_spec.rb
+++ b/Library/Homebrew/test/rubocops/files_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/files"
 
-describe RuboCop::Cop::FormulaAudit::Files do
+RSpec.describe RuboCop::Cop::FormulaAudit::Files do
   subject(:cop) { described_class.new }
 
   context "when auditing files" do
diff --git a/Library/Homebrew/test/rubocops/homepage_spec.rb b/Library/Homebrew/test/rubocops/homepage_spec.rb
index 470940f1a4..8910e3d3c8 100644
--- a/Library/Homebrew/test/rubocops/homepage_spec.rb
+++ b/Library/Homebrew/test/rubocops/homepage_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/homepage"
 
-describe RuboCop::Cop::FormulaAudit::Homepage do
+RSpec.describe RuboCop::Cop::FormulaAudit::Homepage do
   subject(:cop) { described_class.new }
 
   context "when auditing homepage" do
diff --git a/Library/Homebrew/test/rubocops/io_read_spec.rb b/Library/Homebrew/test/rubocops/io_read_spec.rb
index 18038164c4..e26571a726 100644
--- a/Library/Homebrew/test/rubocops/io_read_spec.rb
+++ b/Library/Homebrew/test/rubocops/io_read_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/io_read"
 
-describe RuboCop::Cop::Homebrew::IORead do
+RSpec.describe RuboCop::Cop::Homebrew::IORead do
   subject(:cop) { described_class.new }
 
   it "reports an offense when `IO.read` is used with a pipe character" do
diff --git a/Library/Homebrew/test/rubocops/keg_only_spec.rb b/Library/Homebrew/test/rubocops/keg_only_spec.rb
index 9bbb933fa8..98d365b90d 100644
--- a/Library/Homebrew/test/rubocops/keg_only_spec.rb
+++ b/Library/Homebrew/test/rubocops/keg_only_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/keg_only"
 
-describe RuboCop::Cop::FormulaAudit::KegOnly do
+RSpec.describe RuboCop::Cop::FormulaAudit::KegOnly do
   subject(:cop) { described_class.new }
 
   it "reports and corrects an offense when the `keg_only` reason is capitalized" do
diff --git a/Library/Homebrew/test/rubocops/lines/class_inheritance_spec.rb b/Library/Homebrew/test/rubocops/lines/class_inheritance_spec.rb
index a8d92cf5b2..37903507f0 100644
--- a/Library/Homebrew/test/rubocops/lines/class_inheritance_spec.rb
+++ b/Library/Homebrew/test/rubocops/lines/class_inheritance_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::ClassInheritance do
+RSpec.describe RuboCop::Cop::FormulaAudit::ClassInheritance do
   subject(:cop) { described_class.new }
 
   context "when auditing formula class inheritance" do
diff --git a/Library/Homebrew/test/rubocops/lines/generate_completions_spec.rb b/Library/Homebrew/test/rubocops/lines/generate_completions_spec.rb
index 1981290e29..244e6665ff 100644
--- a/Library/Homebrew/test/rubocops/lines/generate_completions_spec.rb
+++ b/Library/Homebrew/test/rubocops/lines/generate_completions_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit do
+RSpec.describe RuboCop::Cop::FormulaAudit do
   describe RuboCop::Cop::FormulaAudit::GenerateCompletionsDSL do
     subject(:cop) { described_class.new }
 
diff --git a/Library/Homebrew/test/rubocops/lines/quictls_check_spec.rb b/Library/Homebrew/test/rubocops/lines/quictls_check_spec.rb
index c3f8571a86..3ee173448d 100644
--- a/Library/Homebrew/test/rubocops/lines/quictls_check_spec.rb
+++ b/Library/Homebrew/test/rubocops/lines/quictls_check_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::QuicTLSCheck do
+RSpec.describe RuboCop::Cop::FormulaAudit::QuicTLSCheck do
   subject(:cop) { described_class.new }
 
   context "when auditing formula dependencies" do
diff --git a/Library/Homebrew/test/rubocops/lines_spec.rb b/Library/Homebrew/test/rubocops/lines_spec.rb
index 66e8f19c15..d750103587 100644
--- a/Library/Homebrew/test/rubocops/lines_spec.rb
+++ b/Library/Homebrew/test/rubocops/lines_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::Lines do
+RSpec.describe RuboCop::Cop::FormulaAudit::Lines do
   subject(:cop) { described_class.new }
 
   context "when auditing deprecated special dependencies" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/regex_case_insensitive_spec.rb b/Library/Homebrew/test/rubocops/livecheck/regex_case_insensitive_spec.rb
index 95c55b52d0..8ab10c3ed9 100644
--- a/Library/Homebrew/test/rubocops/livecheck/regex_case_insensitive_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/regex_case_insensitive_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckRegexCaseInsensitive do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckRegexCaseInsensitive do
   subject(:cop) { described_class.new }
 
   it "reports an offense when the `regex` is not case-insensitive" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/regex_extension_spec.rb b/Library/Homebrew/test/rubocops/livecheck/regex_extension_spec.rb
index d64656be05..24d4cc7f1c 100644
--- a/Library/Homebrew/test/rubocops/livecheck/regex_extension_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/regex_extension_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckRegexExtension do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckRegexExtension do
   subject(:cop) { described_class.new }
 
   it "reports an offense when the `regex` does not use `\\.t` for archive file extensions" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/regex_if_page_match_spec.rb b/Library/Homebrew/test/rubocops/livecheck/regex_if_page_match_spec.rb
index 9c6e0dc6c6..715d8a0896 100644
--- a/Library/Homebrew/test/rubocops/livecheck/regex_if_page_match_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/regex_if_page_match_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckRegexIfPageMatch do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckRegexIfPageMatch do
   subject(:cop) { described_class.new }
 
   it "reports an offense when there is no `regex` for `strategy :page_match`" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/regex_parentheses_spec.rb b/Library/Homebrew/test/rubocops/livecheck/regex_parentheses_spec.rb
index f30f511fd7..ec515a9c4d 100644
--- a/Library/Homebrew/test/rubocops/livecheck/regex_parentheses_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/regex_parentheses_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckRegexParentheses do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckRegexParentheses do
   subject(:cop) { described_class.new }
 
   it "reports an offense when the `regex` call in the livecheck block does not use parentheses" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/skip_spec.rb b/Library/Homebrew/test/rubocops/livecheck/skip_spec.rb
index 756e4b0a58..d802a008eb 100644
--- a/Library/Homebrew/test/rubocops/livecheck/skip_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/skip_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckSkip do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckSkip do
   subject(:cop) { described_class.new }
 
   it "reports an offense when a skipped formula's livecheck block contains other information" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/url_provided_spec.rb b/Library/Homebrew/test/rubocops/livecheck/url_provided_spec.rb
index 119097608a..0181f985c7 100644
--- a/Library/Homebrew/test/rubocops/livecheck/url_provided_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/url_provided_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckUrlProvided do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckUrlProvided do
   subject(:cop) { described_class.new }
 
   it "reports an offense when a `url` is not specified in the livecheck block" do
diff --git a/Library/Homebrew/test/rubocops/livecheck/url_symbol_spec.rb b/Library/Homebrew/test/rubocops/livecheck/url_symbol_spec.rb
index df82ad4587..3d46fa5350 100644
--- a/Library/Homebrew/test/rubocops/livecheck/url_symbol_spec.rb
+++ b/Library/Homebrew/test/rubocops/livecheck/url_symbol_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/livecheck"
 
-describe RuboCop::Cop::FormulaAudit::LivecheckUrlSymbol do
+RSpec.describe RuboCop::Cop::FormulaAudit::LivecheckUrlSymbol do
   subject(:cop) { described_class.new }
 
   it "reports an offense when the `url` specified in the livecheck block is identical to a formula URL" do
diff --git a/Library/Homebrew/test/rubocops/move_to_extend_os_spec.rb b/Library/Homebrew/test/rubocops/move_to_extend_os_spec.rb
index a03f045860..a20b0d949e 100644
--- a/Library/Homebrew/test/rubocops/move_to_extend_os_spec.rb
+++ b/Library/Homebrew/test/rubocops/move_to_extend_os_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/move_to_extend_os"
 
-describe RuboCop::Cop::Homebrew::MoveToExtendOS do
+RSpec.describe RuboCop::Cop::Homebrew::MoveToExtendOS do
   subject(:cop) { described_class.new }
 
   it "registers an offense when using `OS.linux?`" do
diff --git a/Library/Homebrew/test/rubocops/options_spec.rb b/Library/Homebrew/test/rubocops/options_spec.rb
index 36f088f6cf..5c1d2d376e 100644
--- a/Library/Homebrew/test/rubocops/options_spec.rb
+++ b/Library/Homebrew/test/rubocops/options_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/options"
 
-describe RuboCop::Cop::FormulaAudit::Options do
+RSpec.describe RuboCop::Cop::FormulaAudit::Options do
   subject(:cop) { described_class.new }
 
   context "when auditing options" do
diff --git a/Library/Homebrew/test/rubocops/patches_spec.rb b/Library/Homebrew/test/rubocops/patches_spec.rb
index 3da13ba4a8..55109d662c 100644
--- a/Library/Homebrew/test/rubocops/patches_spec.rb
+++ b/Library/Homebrew/test/rubocops/patches_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/patches"
 
-describe RuboCop::Cop::FormulaAudit::Patches do
+RSpec.describe RuboCop::Cop::FormulaAudit::Patches do
   subject(:cop) { described_class.new }
 
   def expect_offense_hash(message:, severity:, line:, column:, source:)
diff --git a/Library/Homebrew/test/rubocops/present_spec.rb b/Library/Homebrew/test/rubocops/present_spec.rb
index 489b5af4e5..9ee19e8811 100644
--- a/Library/Homebrew/test/rubocops/present_spec.rb
+++ b/Library/Homebrew/test/rubocops/present_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/present"
 
-describe RuboCop::Cop::Homebrew::Present, :config do
+RSpec.describe RuboCop::Cop::Homebrew::Present, :config do
   shared_examples "offense" do |source, correction, message|
     it "registers an offense and corrects" do
       expect_offense(<<~RUBY, source: source, message: message)
diff --git a/Library/Homebrew/test/rubocops/provided_by_macos_spec.rb b/Library/Homebrew/test/rubocops/provided_by_macos_spec.rb
index ed798f3ee8..0fa2145e8c 100644
--- a/Library/Homebrew/test/rubocops/provided_by_macos_spec.rb
+++ b/Library/Homebrew/test/rubocops/provided_by_macos_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/uses_from_macos"
 
-describe RuboCop::Cop::FormulaAudit::ProvidedByMacos do
+RSpec.describe RuboCop::Cop::FormulaAudit::ProvidedByMacos do
   subject(:cop) { described_class.new }
 
   it "fails for formulae not in PROVIDED_BY_MACOS_FORMULAE list" do
diff --git a/Library/Homebrew/test/rubocops/service_spec.rb b/Library/Homebrew/test/rubocops/service_spec.rb
index e8d2d49d5c..2c28212916 100644
--- a/Library/Homebrew/test/rubocops/service_spec.rb
+++ b/Library/Homebrew/test/rubocops/service_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/service"
 
-describe RuboCop::Cop::FormulaAudit::Service do
+RSpec.describe RuboCop::Cop::FormulaAudit::Service do
   subject(:cop) { described_class.new }
 
   it "reports offenses when a service block is missing a required command" do
diff --git a/Library/Homebrew/test/rubocops/text/assert_statements_spec.rb b/Library/Homebrew/test/rubocops/text/assert_statements_spec.rb
index adb26aab4a..3444a0f525 100644
--- a/Library/Homebrew/test/rubocops/text/assert_statements_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/assert_statements_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::AssertStatements do
+RSpec.describe RuboCop::Cop::FormulaAudit::AssertStatements do
   subject(:cop) { described_class.new }
 
   context "when auditing formula assertions" do
diff --git a/Library/Homebrew/test/rubocops/text/comments_spec.rb b/Library/Homebrew/test/rubocops/text/comments_spec.rb
index 9f0b891124..3b1817c473 100644
--- a/Library/Homebrew/test/rubocops/text/comments_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/comments_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::Comments do
+RSpec.describe RuboCop::Cop::FormulaAudit::Comments do
   subject(:cop) { described_class.new }
 
   context "when auditing comment text" do
diff --git a/Library/Homebrew/test/rubocops/text/license_arrays_spec.rb b/Library/Homebrew/test/rubocops/text/license_arrays_spec.rb
index ee51293b72..c009b84c13 100644
--- a/Library/Homebrew/test/rubocops/text/license_arrays_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/license_arrays_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::LicenseArrays do
+RSpec.describe RuboCop::Cop::FormulaAudit::LicenseArrays do
   subject(:cop) { described_class.new }
 
   context "when auditing license arrays" do
diff --git a/Library/Homebrew/test/rubocops/text/licenses_spec.rb b/Library/Homebrew/test/rubocops/text/licenses_spec.rb
index abb1e9fce0..d45c2445bb 100644
--- a/Library/Homebrew/test/rubocops/text/licenses_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/licenses_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::Licenses do
+RSpec.describe RuboCop::Cop::FormulaAudit::Licenses do
   subject(:cop) { described_class.new }
 
   context "when auditing licenses" do
diff --git a/Library/Homebrew/test/rubocops/text/macos_on_linux_spec.rb b/Library/Homebrew/test/rubocops/text/macos_on_linux_spec.rb
index c72c2395fe..c34022e04d 100644
--- a/Library/Homebrew/test/rubocops/text/macos_on_linux_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/macos_on_linux_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::MacOSOnLinux do
+RSpec.describe RuboCop::Cop::FormulaAudit::MacOSOnLinux do
   subject(:cop) { described_class.new }
 
   it "reports an offense when `MacOS` is used in the `Formula` class" do
diff --git a/Library/Homebrew/test/rubocops/text/make_check_spec.rb b/Library/Homebrew/test/rubocops/text/make_check_spec.rb
index cd46299fed..538787b085 100644
--- a/Library/Homebrew/test/rubocops/text/make_check_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/make_check_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAuditStrict::MakeCheck do
+RSpec.describe RuboCop::Cop::FormulaAuditStrict::MakeCheck do
   subject(:cop) { described_class.new }
 
   let(:path) { Tap::TAP_DIRECTORY/"homebrew/homebrew-core" }
diff --git a/Library/Homebrew/test/rubocops/text/miscellaneous_spec.rb b/Library/Homebrew/test/rubocops/text/miscellaneous_spec.rb
index 68bbc9fd4e..03caec6d1f 100644
--- a/Library/Homebrew/test/rubocops/text/miscellaneous_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/miscellaneous_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::Miscellaneous do
+RSpec.describe RuboCop::Cop::FormulaAudit::Miscellaneous do
   subject(:cop) { described_class.new }
 
   context "when auditing formula miscellany" do
diff --git a/Library/Homebrew/test/rubocops/text/mpi_check_spec.rb b/Library/Homebrew/test/rubocops/text/mpi_check_spec.rb
index e696904ed3..986f689c75 100644
--- a/Library/Homebrew/test/rubocops/text/mpi_check_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/mpi_check_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::MpiCheck do
+RSpec.describe RuboCop::Cop::FormulaAudit::MpiCheck do
   subject(:cop) { described_class.new }
 
   context "when auditing MPI dependencies" do
diff --git a/Library/Homebrew/test/rubocops/text/on_system_conditionals_spec.rb b/Library/Homebrew/test/rubocops/text/on_system_conditionals_spec.rb
index 54b6510faf..9757208197 100644
--- a/Library/Homebrew/test/rubocops/text/on_system_conditionals_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/on_system_conditionals_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::OnSystemConditionals do
+RSpec.describe RuboCop::Cop::FormulaAudit::OnSystemConditionals do
   subject(:cop) { described_class.new }
 
   context "when auditing OS conditionals" do
diff --git a/Library/Homebrew/test/rubocops/text/option_declarations_spec.rb b/Library/Homebrew/test/rubocops/text/option_declarations_spec.rb
index ad6feb1031..b14e6daafd 100644
--- a/Library/Homebrew/test/rubocops/text/option_declarations_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/option_declarations_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::OptionDeclarations do
+RSpec.describe RuboCop::Cop::FormulaAudit::OptionDeclarations do
   subject(:cop) { described_class.new }
 
   context "when auditing options" do
diff --git a/Library/Homebrew/test/rubocops/text/python_versions_spec.rb b/Library/Homebrew/test/rubocops/text/python_versions_spec.rb
index f1a3fd8943..0a6fcbe960 100644
--- a/Library/Homebrew/test/rubocops/text/python_versions_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/python_versions_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::PythonVersions do
+RSpec.describe RuboCop::Cop::FormulaAudit::PythonVersions do
   subject(:cop) { described_class.new }
 
   context "when auditing Python versions" do
diff --git a/Library/Homebrew/test/rubocops/text/safe_popen_commands_spec.rb b/Library/Homebrew/test/rubocops/text/safe_popen_commands_spec.rb
index 989f069ee0..f8d8d7b13a 100644
--- a/Library/Homebrew/test/rubocops/text/safe_popen_commands_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/safe_popen_commands_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::SafePopenCommands do
+RSpec.describe RuboCop::Cop::FormulaAudit::SafePopenCommands do
   subject(:cop) { described_class.new }
 
   context "when auditing popen commands" do
diff --git a/Library/Homebrew/test/rubocops/text/shell_variables_spec.rb b/Library/Homebrew/test/rubocops/text/shell_variables_spec.rb
index 60d4f16c71..f985b9192a 100644
--- a/Library/Homebrew/test/rubocops/text/shell_variables_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/shell_variables_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/lines"
 
-describe RuboCop::Cop::FormulaAudit::ShellVariables do
+RSpec.describe RuboCop::Cop::FormulaAudit::ShellVariables do
   subject(:cop) { described_class.new }
 
   context "when auditing shell variables" do
diff --git a/Library/Homebrew/test/rubocops/text/strict_spec.rb b/Library/Homebrew/test/rubocops/text/strict_spec.rb
index 66315f4d9d..339bb77f24 100644
--- a/Library/Homebrew/test/rubocops/text/strict_spec.rb
+++ b/Library/Homebrew/test/rubocops/text/strict_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/text"
 
-describe RuboCop::Cop::FormulaAuditStrict::Text do
+RSpec.describe RuboCop::Cop::FormulaAuditStrict::Text do
   subject(:cop) { described_class.new }
 
   context "when auditing formula text in homebrew/core" do
diff --git a/Library/Homebrew/test/rubocops/text_spec.rb b/Library/Homebrew/test/rubocops/text_spec.rb
index 01b1e89381..c37f49e1e6 100644
--- a/Library/Homebrew/test/rubocops/text_spec.rb
+++ b/Library/Homebrew/test/rubocops/text_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/text"
 
-describe RuboCop::Cop::FormulaAudit::Text do
+RSpec.describe RuboCop::Cop::FormulaAudit::Text do
   subject(:cop) { described_class.new }
 
   context "when auditing formula text" do
diff --git a/Library/Homebrew/test/rubocops/urls/git_spec.rb b/Library/Homebrew/test/rubocops/urls/git_spec.rb
index dd33ac1be6..c95deae3e2 100644
--- a/Library/Homebrew/test/rubocops/urls/git_spec.rb
+++ b/Library/Homebrew/test/rubocops/urls/git_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/urls"
 
-describe RuboCop::Cop::FormulaAudit::GitUrls do
+RSpec.describe RuboCop::Cop::FormulaAudit::GitUrls do
   subject(:cop) { described_class.new }
 
   context "when a git URL is used" do
diff --git a/Library/Homebrew/test/rubocops/urls/git_strict_spec.rb b/Library/Homebrew/test/rubocops/urls/git_strict_spec.rb
index eb4c644c7a..1e511173d1 100644
--- a/Library/Homebrew/test/rubocops/urls/git_strict_spec.rb
+++ b/Library/Homebrew/test/rubocops/urls/git_strict_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/urls"
 
-describe RuboCop::Cop::FormulaAuditStrict::GitUrls do
+RSpec.describe RuboCop::Cop::FormulaAuditStrict::GitUrls do
   subject(:cop) { described_class.new }
 
   context "when a git URL is used" do
diff --git a/Library/Homebrew/test/rubocops/urls/pypi_spec.rb b/Library/Homebrew/test/rubocops/urls/pypi_spec.rb
index e4793b30c4..f4d1186ead 100644
--- a/Library/Homebrew/test/rubocops/urls/pypi_spec.rb
+++ b/Library/Homebrew/test/rubocops/urls/pypi_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/urls"
 
-describe RuboCop::Cop::FormulaAudit::PyPiUrls do
+RSpec.describe RuboCop::Cop::FormulaAudit::PyPiUrls do
   subject(:cop) { described_class.new }
 
   context "when a pypi URL is used" do
diff --git a/Library/Homebrew/test/rubocops/urls_spec.rb b/Library/Homebrew/test/rubocops/urls_spec.rb
index 4e88c108a4..2a887c2397 100644
--- a/Library/Homebrew/test/rubocops/urls_spec.rb
+++ b/Library/Homebrew/test/rubocops/urls_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/urls"
 
-describe RuboCop::Cop::FormulaAudit::Urls do
+RSpec.describe RuboCop::Cop::FormulaAudit::Urls do
   subject(:cop) { described_class.new }
 
   let(:offense_list) do
diff --git a/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb b/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
index 626ff1e64c..5d00eb4f7c 100644
--- a/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
+++ b/Library/Homebrew/test/rubocops/uses_from_macos_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/uses_from_macos"
 
-describe RuboCop::Cop::FormulaAudit::UsesFromMacos do
+RSpec.describe RuboCop::Cop::FormulaAudit::UsesFromMacos do
   subject(:cop) { described_class.new }
 
   context "when auditing `uses_from_macos` dependencies" do
diff --git a/Library/Homebrew/test/rubocops/version_spec.rb b/Library/Homebrew/test/rubocops/version_spec.rb
index a30544dcaf..c4c9dfef1e 100644
--- a/Library/Homebrew/test/rubocops/version_spec.rb
+++ b/Library/Homebrew/test/rubocops/version_spec.rb
@@ -2,7 +2,7 @@
 
 require "rubocops/version"
 
-describe RuboCop::Cop::FormulaAudit::Version do
+RSpec.describe RuboCop::Cop::FormulaAudit::Version do
   subject(:cop) { described_class.new }
 
   context "when auditing version" do
diff --git a/Library/Homebrew/test/sandbox_spec.rb b/Library/Homebrew/test/sandbox_spec.rb
index f657d1ebf5..26882f410c 100644
--- a/Library/Homebrew/test/sandbox_spec.rb
+++ b/Library/Homebrew/test/sandbox_spec.rb
@@ -2,7 +2,7 @@
 
 require "sandbox"
 
-describe Sandbox, :needs_macos do
+RSpec.describe Sandbox, :needs_macos do
   define_negated_matcher :not_matching, :matching
 
   subject(:sandbox) { described_class.new }
diff --git a/Library/Homebrew/test/search_spec.rb b/Library/Homebrew/test/search_spec.rb
index 3509119f85..dc67320fde 100644
--- a/Library/Homebrew/test/search_spec.rb
+++ b/Library/Homebrew/test/search_spec.rb
@@ -2,7 +2,7 @@
 
 require "search"
 
-describe Homebrew::Search do
+RSpec.describe Homebrew::Search do
   describe "#query_regexp" do
     it "correctly parses a regex query" do
       expect(described_class.query_regexp("/^query$/")).to eq(/^query$/)
diff --git a/Library/Homebrew/test/service_spec.rb b/Library/Homebrew/test/service_spec.rb
index b5c56fe40b..7b0c43cebb 100644
--- a/Library/Homebrew/test/service_spec.rb
+++ b/Library/Homebrew/test/service_spec.rb
@@ -3,7 +3,7 @@
 require "formula"
 require "service"
 
-describe Homebrew::Service do
+RSpec.describe Homebrew::Service do
   let(:name) { "formula_name" }
 
   def stub_formula(&block)
diff --git a/Library/Homebrew/test/settings_spec.rb b/Library/Homebrew/test/settings_spec.rb
index 40ef77f683..a1a2a409fa 100644
--- a/Library/Homebrew/test/settings_spec.rb
+++ b/Library/Homebrew/test/settings_spec.rb
@@ -2,7 +2,7 @@
 
 require "settings"
 
-describe Homebrew::Settings do
+RSpec.describe Homebrew::Settings do
   before do
     HOMEBREW_REPOSITORY.cd do
       system "git", "init"
diff --git a/Library/Homebrew/test/simulate_system_spec.rb b/Library/Homebrew/test/simulate_system_spec.rb
index 352549f9fe..c0856fe397 100644
--- a/Library/Homebrew/test/simulate_system_spec.rb
+++ b/Library/Homebrew/test/simulate_system_spec.rb
@@ -2,7 +2,7 @@
 
 require "settings"
 
-describe Homebrew::SimulateSystem do
+RSpec.describe Homebrew::SimulateSystem do
   after do
     described_class.clear
   end
diff --git a/Library/Homebrew/test/software_spec/bottle_spec.rb b/Library/Homebrew/test/software_spec/bottle_spec.rb
index 3c9c015768..98aa029bcd 100644
--- a/Library/Homebrew/test/software_spec/bottle_spec.rb
+++ b/Library/Homebrew/test/software_spec/bottle_spec.rb
@@ -2,7 +2,7 @@
 
 require "software_spec"
 
-describe BottleSpecification do
+RSpec.describe BottleSpecification do
   subject(:bottle_spec) { described_class.new }
 
   describe "#sha256" do
diff --git a/Library/Homebrew/test/software_spec/head_spec.rb b/Library/Homebrew/test/software_spec/head_spec.rb
index 3037fb9f92..eee9e59676 100644
--- a/Library/Homebrew/test/software_spec/head_spec.rb
+++ b/Library/Homebrew/test/software_spec/head_spec.rb
@@ -2,7 +2,7 @@
 
 require "software_spec"
 
-describe HeadSoftwareSpec do
+RSpec.describe HeadSoftwareSpec do
   subject(:head_spec) { described_class.new }
 
   specify "#version" do
diff --git a/Library/Homebrew/test/software_spec_spec.rb b/Library/Homebrew/test/software_spec_spec.rb
index 069856c2a9..37770dac9e 100644
--- a/Library/Homebrew/test/software_spec_spec.rb
+++ b/Library/Homebrew/test/software_spec_spec.rb
@@ -2,7 +2,7 @@
 
 require "software_spec"
 
-describe SoftwareSpec do
+RSpec.describe SoftwareSpec do
   alias_matcher :have_defined_resource, :be_resource_defined
   alias_matcher :have_defined_option, :be_option_defined
 
diff --git a/Library/Homebrew/test/style_spec.rb b/Library/Homebrew/test/style_spec.rb
index e5c0f7eb0a..511f04dcdc 100644
--- a/Library/Homebrew/test/style_spec.rb
+++ b/Library/Homebrew/test/style_spec.rb
@@ -2,7 +2,7 @@
 
 require "style"
 
-describe Homebrew::Style do
+RSpec.describe Homebrew::Style do
   around do |example|
     FileUtils.ln_s HOMEBREW_LIBRARY_PATH, HOMEBREW_LIBRARY/"Homebrew"
     FileUtils.ln_s HOMEBREW_LIBRARY_PATH.parent/".rubocop.yml", HOMEBREW_LIBRARY/".rubocop.yml"
diff --git a/Library/Homebrew/test/system_command_result_spec.rb b/Library/Homebrew/test/system_command_result_spec.rb
index 739888791c..a985fc9010 100644
--- a/Library/Homebrew/test/system_command_result_spec.rb
+++ b/Library/Homebrew/test/system_command_result_spec.rb
@@ -2,7 +2,7 @@
 
 require "system_command"
 
-describe SystemCommand::Result do
+RSpec.describe SystemCommand::Result do
   subject(:result) do
     described_class.new([], output_array, instance_double(Process::Status, exitstatus: 0, success?: true),
                         secrets: [])
diff --git a/Library/Homebrew/test/system_command_spec.rb b/Library/Homebrew/test/system_command_spec.rb
index 8c4b9e8fd5..1dd0c519cd 100644
--- a/Library/Homebrew/test/system_command_spec.rb
+++ b/Library/Homebrew/test/system_command_spec.rb
@@ -2,7 +2,7 @@
 
 require "system_command"
 
-describe SystemCommand do
+RSpec.describe SystemCommand do
   describe "#initialize" do
     subject(:command) do
       described_class.new(
diff --git a/Library/Homebrew/test/tab_spec.rb b/Library/Homebrew/test/tab_spec.rb
index 267a5349cc..2a4865411e 100644
--- a/Library/Homebrew/test/tab_spec.rb
+++ b/Library/Homebrew/test/tab_spec.rb
@@ -3,7 +3,7 @@
 require "tab"
 require "formula"
 
-describe Tab do
+RSpec.describe Tab do
   alias_matcher :be_built_with, :be_with
 
   matcher :be_poured_from_bottle do
diff --git a/Library/Homebrew/test/tap_spec.rb b/Library/Homebrew/test/tap_spec.rb
index 7da80b9d80..f016d7a28e 100644
--- a/Library/Homebrew/test/tap_spec.rb
+++ b/Library/Homebrew/test/tap_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Tap do
+RSpec.describe Tap do
   alias_matcher :have_formula_file, :be_formula_file
   alias_matcher :have_custom_remote, :be_custom_remote
 
diff --git a/Library/Homebrew/test/test_runner_formula_spec.rb b/Library/Homebrew/test/test_runner_formula_spec.rb
index ceb1debd1f..2f46c3598a 100644
--- a/Library/Homebrew/test/test_runner_formula_spec.rb
+++ b/Library/Homebrew/test/test_runner_formula_spec.rb
@@ -3,7 +3,7 @@
 require "test_runner_formula"
 require "test/support/fixtures/testball"
 
-describe TestRunnerFormula do
+RSpec.describe TestRunnerFormula do
   let(:testball) { Testball.new }
   let(:xcode_helper) { setup_test_formula("xcode-helper", [:macos]) }
   let(:linux_kernel_requirer) { setup_test_formula("linux-kernel-requirer", [:linux]) }
diff --git a/Library/Homebrew/test/uninstall_spec.rb b/Library/Homebrew/test/uninstall_spec.rb
index a1d2822ecc..e4cc7d1f91 100644
--- a/Library/Homebrew/test/uninstall_spec.rb
+++ b/Library/Homebrew/test/uninstall_spec.rb
@@ -2,7 +2,7 @@
 
 require "uninstall"
 
-describe Homebrew::Uninstall do
+RSpec.describe Homebrew::Uninstall do
   let(:dependency) { formula("dependency") { url "f-1" } }
 
   let(:dependent_formula) do
diff --git a/Library/Homebrew/test/unpack_strategy/bazaar_spec.rb b/Library/Homebrew/test/unpack_strategy/bazaar_spec.rb
index 94ae447efa..22d6470a59 100644
--- a/Library/Homebrew/test/unpack_strategy/bazaar_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/bazaar_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Bazaar do
+RSpec.describe UnpackStrategy::Bazaar do
   let(:repo) do
     mktmpdir.tap do |repo|
       FileUtils.touch repo/"test"
diff --git a/Library/Homebrew/test/unpack_strategy/bzip2_spec.rb b/Library/Homebrew/test/unpack_strategy/bzip2_spec.rb
index a81f15bab1..1855bc58d9 100644
--- a/Library/Homebrew/test/unpack_strategy/bzip2_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/bzip2_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Bzip2 do
+RSpec.describe UnpackStrategy::Bzip2 do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.bz2" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/cvs_spec.rb b/Library/Homebrew/test/unpack_strategy/cvs_spec.rb
index 854b76c0f0..6234465c16 100644
--- a/Library/Homebrew/test/unpack_strategy/cvs_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/cvs_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Cvs do
+RSpec.describe UnpackStrategy::Cvs do
   let(:repo) do
     mktmpdir.tap do |repo|
       FileUtils.touch repo/"test"
diff --git a/Library/Homebrew/test/unpack_strategy/directory_spec.rb b/Library/Homebrew/test/unpack_strategy/directory_spec.rb
index 669d040764..d1320f808c 100644
--- a/Library/Homebrew/test/unpack_strategy/directory_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/directory_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Directory do
+RSpec.describe UnpackStrategy::Directory do
   subject(:strategy) { described_class.new(path) }
 
   let(:path) do
diff --git a/Library/Homebrew/test/unpack_strategy/dmg_spec.rb b/Library/Homebrew/test/unpack_strategy/dmg_spec.rb
index 8a3594f144..5099921249 100644
--- a/Library/Homebrew/test/unpack_strategy/dmg_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/dmg_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Dmg, :needs_macos do
+RSpec.describe UnpackStrategy::Dmg, :needs_macos do
   describe "#mount" do
     let(:path) { TEST_FIXTURE_DIR/"cask/container.dmg" }
 
diff --git a/Library/Homebrew/test/unpack_strategy/git_spec.rb b/Library/Homebrew/test/unpack_strategy/git_spec.rb
index 869df2e091..0d8cd311a9 100644
--- a/Library/Homebrew/test/unpack_strategy/git_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/git_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Git do
+RSpec.describe UnpackStrategy::Git do
   let(:repo) do
     mktmpdir.tap do |repo|
       system "git", "-C", repo, "init"
diff --git a/Library/Homebrew/test/unpack_strategy/gzip_spec.rb b/Library/Homebrew/test/unpack_strategy/gzip_spec.rb
index ebf4a493bd..b91668e726 100644
--- a/Library/Homebrew/test/unpack_strategy/gzip_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/gzip_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Gzip do
+RSpec.describe UnpackStrategy::Gzip do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.gz" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/jar_spec.rb b/Library/Homebrew/test/unpack_strategy/jar_spec.rb
index f6da64b973..cd3e3108e4 100644
--- a/Library/Homebrew/test/unpack_strategy/jar_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/jar_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Jar, :needs_unzip do
+RSpec.describe UnpackStrategy::Jar, :needs_unzip do
   let(:path) { TEST_FIXTURE_DIR/"test.jar" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/lha_spec.rb b/Library/Homebrew/test/unpack_strategy/lha_spec.rb
index e24a60a655..caff62bfcd 100644
--- a/Library/Homebrew/test/unpack_strategy/lha_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/lha_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Lha do
+RSpec.describe UnpackStrategy::Lha do
   let(:path) { TEST_FIXTURE_DIR/"test.lha" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/lzip_spec.rb b/Library/Homebrew/test/unpack_strategy/lzip_spec.rb
index a74b68add5..eb809f4e60 100644
--- a/Library/Homebrew/test/unpack_strategy/lzip_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/lzip_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Lzip do
+RSpec.describe UnpackStrategy::Lzip do
   let(:path) { TEST_FIXTURE_DIR/"test.lz" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/mercurial_spec.rb b/Library/Homebrew/test/unpack_strategy/mercurial_spec.rb
index 721af10b62..90ae85a5bd 100644
--- a/Library/Homebrew/test/unpack_strategy/mercurial_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/mercurial_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Mercurial do
+RSpec.describe UnpackStrategy::Mercurial do
   let(:repo) do
     mktmpdir.tap do |repo|
       (repo/".hg").mkpath
diff --git a/Library/Homebrew/test/unpack_strategy/p7zip_spec.rb b/Library/Homebrew/test/unpack_strategy/p7zip_spec.rb
index c612b13f03..8785155ec3 100644
--- a/Library/Homebrew/test/unpack_strategy/p7zip_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/p7zip_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::P7Zip do
+RSpec.describe UnpackStrategy::P7Zip do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.7z" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/rar_spec.rb b/Library/Homebrew/test/unpack_strategy/rar_spec.rb
index 5e5e593339..c5f8c406ba 100644
--- a/Library/Homebrew/test/unpack_strategy/rar_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/rar_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Rar do
+RSpec.describe UnpackStrategy::Rar do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.rar" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/subversion_spec.rb b/Library/Homebrew/test/unpack_strategy/subversion_spec.rb
index 78795f94cc..fea9fd702f 100644
--- a/Library/Homebrew/test/unpack_strategy/subversion_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/subversion_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Subversion, :needs_svn do
+RSpec.describe UnpackStrategy::Subversion, :needs_svn do
   let(:repo) { mktmpdir }
   let(:working_copy) { mktmpdir }
   let(:path) { working_copy }
diff --git a/Library/Homebrew/test/unpack_strategy/tar_spec.rb b/Library/Homebrew/test/unpack_strategy/tar_spec.rb
index 2c8fac9549..0307e41210 100644
--- a/Library/Homebrew/test/unpack_strategy/tar_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/tar_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Tar do
+RSpec.describe UnpackStrategy::Tar do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.tar.gz" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/uncompressed_spec.rb b/Library/Homebrew/test/unpack_strategy/uncompressed_spec.rb
index efd99dc90f..19341c733f 100644
--- a/Library/Homebrew/test/unpack_strategy/uncompressed_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/uncompressed_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Uncompressed do
+RSpec.describe UnpackStrategy::Uncompressed do
   let(:path) do
     (mktmpdir/"test").tap do |path|
       FileUtils.touch path
diff --git a/Library/Homebrew/test/unpack_strategy/xar_spec.rb b/Library/Homebrew/test/unpack_strategy/xar_spec.rb
index f4f11389d1..41b7a0b558 100644
--- a/Library/Homebrew/test/unpack_strategy/xar_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/xar_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Xar, :needs_macos do
+RSpec.describe UnpackStrategy::Xar, :needs_macos do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.xar" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/xz_spec.rb b/Library/Homebrew/test/unpack_strategy/xz_spec.rb
index ffc41369ae..efdac2253a 100644
--- a/Library/Homebrew/test/unpack_strategy/xz_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/xz_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Xz do
+RSpec.describe UnpackStrategy::Xz do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.xz" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/zip_spec.rb b/Library/Homebrew/test/unpack_strategy/zip_spec.rb
index 10a0983a50..cc2c4c5d16 100644
--- a/Library/Homebrew/test/unpack_strategy/zip_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/zip_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Zip do
+RSpec.describe UnpackStrategy::Zip do
   let(:path) { TEST_FIXTURE_DIR/"cask/MyFancyApp.zip" }
 
   include_examples "UnpackStrategy::detect"
diff --git a/Library/Homebrew/test/unpack_strategy/zstd_spec.rb b/Library/Homebrew/test/unpack_strategy/zstd_spec.rb
index 706ec4dad1..2fe9b40f16 100644
--- a/Library/Homebrew/test/unpack_strategy/zstd_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy/zstd_spec.rb
@@ -2,7 +2,7 @@
 
 require_relative "shared_examples"
 
-describe UnpackStrategy::Zstd do
+RSpec.describe UnpackStrategy::Zstd do
   let(:path) { TEST_FIXTURE_DIR/"cask/container.tar.zst" }
 
   it "is correctly detected" do
diff --git a/Library/Homebrew/test/unpack_strategy_spec.rb b/Library/Homebrew/test/unpack_strategy_spec.rb
index 9082fdc04b..7218aa6f46 100644
--- a/Library/Homebrew/test/unpack_strategy_spec.rb
+++ b/Library/Homebrew/test/unpack_strategy_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe UnpackStrategy do
+RSpec.describe UnpackStrategy do
   describe "#extract_nestedly" do
     subject(:strategy) { described_class.detect(path) }
 
diff --git a/Library/Homebrew/test/utils/analytics_spec.rb b/Library/Homebrew/test/utils/analytics_spec.rb
index de194d916c..dc2100336f 100644
--- a/Library/Homebrew/test/utils/analytics_spec.rb
+++ b/Library/Homebrew/test/utils/analytics_spec.rb
@@ -3,7 +3,7 @@
 require "utils/analytics"
 require "formula_installer"
 
-describe Utils::Analytics do
+RSpec.describe Utils::Analytics do
   before do
     described_class.clear_cache
   end
diff --git a/Library/Homebrew/test/utils/ast/ast_spec.rb b/Library/Homebrew/test/utils/ast/ast_spec.rb
index 38fb349b69..cdd35b7854 100644
--- a/Library/Homebrew/test/utils/ast/ast_spec.rb
+++ b/Library/Homebrew/test/utils/ast/ast_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/ast"
 
-describe Utils::AST do
+RSpec.describe Utils::AST do
   describe ".stanza_text" do
     let(:compound_license) do
       <<-RUBY
diff --git a/Library/Homebrew/test/utils/ast/formula_ast_spec.rb b/Library/Homebrew/test/utils/ast/formula_ast_spec.rb
index 643b874f60..e97a307364 100644
--- a/Library/Homebrew/test/utils/ast/formula_ast_spec.rb
+++ b/Library/Homebrew/test/utils/ast/formula_ast_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/ast"
 
-describe Utils::AST::FormulaAST do
+RSpec.describe Utils::AST::FormulaAST do
   subject(:formula_ast) do
     described_class.new <<~RUBY
       class Foo < Formula
diff --git a/Library/Homebrew/test/utils/autoremove_spec.rb b/Library/Homebrew/test/utils/autoremove_spec.rb
index 51ce249bb9..0bdbcbe2ce 100644
--- a/Library/Homebrew/test/utils/autoremove_spec.rb
+++ b/Library/Homebrew/test/utils/autoremove_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/autoremove"
 
-describe Utils::Autoremove do
+RSpec.describe Utils::Autoremove do
   shared_context "with formulae for dependency testing" do
     let(:formula_with_deps) do
       formula "zero" do
diff --git a/Library/Homebrew/test/utils/backtrace_spec.rb b/Library/Homebrew/test/utils/backtrace_spec.rb
index 3757c38da2..79166ada28 100644
--- a/Library/Homebrew/test/utils/backtrace_spec.rb
+++ b/Library/Homebrew/test/utils/backtrace_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/backtrace"
 
-describe Utils::Backtrace do
+RSpec.describe Utils::Backtrace do
   let(:backtrace_no_sorbet_paths) do
     [
       "/Library/Homebrew/downloadable.rb:75:in",
diff --git a/Library/Homebrew/test/utils/bottles/bottles_spec.rb b/Library/Homebrew/test/utils/bottles/bottles_spec.rb
index 7af427a399..6a46d30ccd 100644
--- a/Library/Homebrew/test/utils/bottles/bottles_spec.rb
+++ b/Library/Homebrew/test/utils/bottles/bottles_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/bottles"
 
-describe Utils::Bottles do
+RSpec.describe Utils::Bottles do
   describe "#tag", :needs_macos do
     it "returns :big_sur or :arm64_big_sur on Big Sur" do
       allow(MacOS).to receive(:version).and_return(MacOSVersion.new("11.0"))
diff --git a/Library/Homebrew/test/utils/bottles/collector_spec.rb b/Library/Homebrew/test/utils/bottles/collector_spec.rb
index b0356f059d..de10dbb541 100644
--- a/Library/Homebrew/test/utils/bottles/collector_spec.rb
+++ b/Library/Homebrew/test/utils/bottles/collector_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/bottles"
 
-describe Utils::Bottles::Collector do
+RSpec.describe Utils::Bottles::Collector do
   subject(:collector) { described_class.new }
 
   let(:catalina) { Utils::Bottles::Tag.from_symbol(:catalina) }
diff --git a/Library/Homebrew/test/utils/bottles/tag_spec.rb b/Library/Homebrew/test/utils/bottles/tag_spec.rb
index b290293b7f..cddf686c11 100644
--- a/Library/Homebrew/test/utils/bottles/tag_spec.rb
+++ b/Library/Homebrew/test/utils/bottles/tag_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/bottles"
 
-describe Utils::Bottles::Tag do
+RSpec.describe Utils::Bottles::Tag do
   it "can parse macOS symbols with archs" do
     symbol = :arm64_big_sur
     tag = described_class.from_symbol(symbol)
diff --git a/Library/Homebrew/test/utils/curl_spec.rb b/Library/Homebrew/test/utils/curl_spec.rb
index 25c473fd9a..66791b1036 100644
--- a/Library/Homebrew/test/utils/curl_spec.rb
+++ b/Library/Homebrew/test/utils/curl_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/curl"
 
-describe "Utils::Curl" do
+RSpec.describe "Utils::Curl" do
   include Utils::Curl
 
   let(:details) do
diff --git a/Library/Homebrew/test/utils/fork_spec.rb b/Library/Homebrew/test/utils/fork_spec.rb
index 317f17b0ba..eba4c65925 100644
--- a/Library/Homebrew/test/utils/fork_spec.rb
+++ b/Library/Homebrew/test/utils/fork_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/fork"
 
-describe Utils do
+RSpec.describe Utils do
   describe "#safe_fork" do
     it "raises a RuntimeError on an error that isn't ErrorDuringExecution" do
       expect do
diff --git a/Library/Homebrew/test/utils/git_repository_spec.rb b/Library/Homebrew/test/utils/git_repository_spec.rb
index ae6d7a9998..19ff66171f 100644
--- a/Library/Homebrew/test/utils/git_repository_spec.rb
+++ b/Library/Homebrew/test/utils/git_repository_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/git_repository"
 
-describe Utils do
+RSpec.describe Utils do
   shared_examples "git_repository helper function" do |method_name|
     context "when directory is not a Git repository" do
       it "returns nil if `safe` parameter is `false`" do
diff --git a/Library/Homebrew/test/utils/git_spec.rb b/Library/Homebrew/test/utils/git_spec.rb
index a7129cd1af..2efec2fa07 100644
--- a/Library/Homebrew/test/utils/git_spec.rb
+++ b/Library/Homebrew/test/utils/git_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/git"
 
-describe Utils::Git do
+RSpec.describe Utils::Git do
   around do |example|
     described_class.clear_available_cache
     example.run
diff --git a/Library/Homebrew/test/utils/github/actions_spec.rb b/Library/Homebrew/test/utils/github/actions_spec.rb
index 9a40bcd739..9c677d123c 100644
--- a/Library/Homebrew/test/utils/github/actions_spec.rb
+++ b/Library/Homebrew/test/utils/github/actions_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/github/actions"
 
-describe GitHub::Actions::Annotation do
+RSpec.describe GitHub::Actions::Annotation do
   let(:message) { "lorem ipsum" }
 
   describe "#new" do
diff --git a/Library/Homebrew/test/utils/github_spec.rb b/Library/Homebrew/test/utils/github_spec.rb
index d5b0fe7c55..c21a7ae6a4 100644
--- a/Library/Homebrew/test/utils/github_spec.rb
+++ b/Library/Homebrew/test/utils/github_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/github"
 
-describe GitHub do
+RSpec.describe GitHub do
   describe "::search_query_string" do
     it "builds a query with the given hash parameters formatted as key:value" do
       query = described_class.search_query_string(user: "Homebrew", repo: "brew")
diff --git a/Library/Homebrew/test/utils/gzip_spec.rb b/Library/Homebrew/test/utils/gzip_spec.rb
index ceb3ea864a..9412f756b0 100644
--- a/Library/Homebrew/test/utils/gzip_spec.rb
+++ b/Library/Homebrew/test/utils/gzip_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/gzip"
 
-describe Utils::Gzip do
+RSpec.describe Utils::Gzip do
   describe "compress_with_options" do
     it "uses the explicitly specified mtime, orig_name, and output path when passed" do
       mktmpdir do |path|
diff --git a/Library/Homebrew/test/utils/inreplace_spec.rb b/Library/Homebrew/test/utils/inreplace_spec.rb
index 20c91672d9..a6b0a044b5 100644
--- a/Library/Homebrew/test/utils/inreplace_spec.rb
+++ b/Library/Homebrew/test/utils/inreplace_spec.rb
@@ -3,7 +3,7 @@
 require "tempfile"
 require "utils/inreplace"
 
-describe Utils::Inreplace do
+RSpec.describe Utils::Inreplace do
   let(:file) { Tempfile.new("test") }
 
   before do
diff --git a/Library/Homebrew/test/utils/popen_spec.rb b/Library/Homebrew/test/utils/popen_spec.rb
index 67c37ac9b8..c4cef2afe6 100644
--- a/Library/Homebrew/test/utils/popen_spec.rb
+++ b/Library/Homebrew/test/utils/popen_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/popen"
 
-describe Utils do
+RSpec.describe Utils do
   describe "::popen_read" do
     it "reads the standard output of a given command" do
       expect(described_class.popen_read("sh", "-c", "echo success").chomp).to eq("success")
diff --git a/Library/Homebrew/test/utils/pypi_spec.rb b/Library/Homebrew/test/utils/pypi_spec.rb
index e3ca858d1d..f5f529e143 100644
--- a/Library/Homebrew/test/utils/pypi_spec.rb
+++ b/Library/Homebrew/test/utils/pypi_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/pypi"
 
-describe PyPI do
+RSpec.describe PyPI do
   let(:pypi_package_url) do
     "https://files.pythonhosted.org/packages/b0/3f/2e1dad67eb172b6443b5eb37eb885a054a55cfd733393071499514140282/" \
       "snakemake-5.29.0.tar.gz"
diff --git a/Library/Homebrew/test/utils/ruby_check_version_script_spec.rb b/Library/Homebrew/test/utils/ruby_check_version_script_spec.rb
index 86e88af7a6..5f6786be09 100644
--- a/Library/Homebrew/test/utils/ruby_check_version_script_spec.rb
+++ b/Library/Homebrew/test/utils/ruby_check_version_script_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Utils do
+RSpec.describe Utils do
   describe "ruby_check_version_script" do
     subject do
       homebrew_env = ENV.select { |key, _| key.start_with?("HOMEBREW_") }
diff --git a/Library/Homebrew/test/utils/shell_spec.rb b/Library/Homebrew/test/utils/shell_spec.rb
index c735a9da57..b5f8d9b6d6 100644
--- a/Library/Homebrew/test/utils/shell_spec.rb
+++ b/Library/Homebrew/test/utils/shell_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/shell"
 
-describe Utils::Shell do
+RSpec.describe Utils::Shell do
   describe "::profile" do
     it "returns ~/.profile by default" do
       ENV["SHELL"] = "/bin/another_shell"
diff --git a/Library/Homebrew/test/utils/spdx_spec.rb b/Library/Homebrew/test/utils/spdx_spec.rb
index ad9aa82852..4cbc490866 100644
--- a/Library/Homebrew/test/utils/spdx_spec.rb
+++ b/Library/Homebrew/test/utils/spdx_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/spdx"
 
-describe SPDX do
+RSpec.describe SPDX do
   describe ".license_data" do
     it "has the license list version" do
       expect(described_class.license_data["licenseListVersion"]).not_to be_nil
diff --git a/Library/Homebrew/test/utils/string_inreplace_extension_spec.rb b/Library/Homebrew/test/utils/string_inreplace_extension_spec.rb
index 5a73b525e2..1285613a24 100644
--- a/Library/Homebrew/test/utils/string_inreplace_extension_spec.rb
+++ b/Library/Homebrew/test/utils/string_inreplace_extension_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/string_inreplace_extension"
 
-describe StringInreplaceExtension do
+RSpec.describe StringInreplaceExtension do
   subject(:string_extension) { described_class.new(string.dup) }
 
   describe "#change_make_var!" do
diff --git a/Library/Homebrew/test/utils/svn_spec.rb b/Library/Homebrew/test/utils/svn_spec.rb
index 60556601a4..59bd5c05d6 100644
--- a/Library/Homebrew/test/utils/svn_spec.rb
+++ b/Library/Homebrew/test/utils/svn_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/svn"
 
-describe Utils::Svn do
+RSpec.describe Utils::Svn do
   before do
     described_class.clear_version_cache
   end
diff --git a/Library/Homebrew/test/utils/tar_spec.rb b/Library/Homebrew/test/utils/tar_spec.rb
index b3569cad80..418c95bd4e 100644
--- a/Library/Homebrew/test/utils/tar_spec.rb
+++ b/Library/Homebrew/test/utils/tar_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/tar"
 
-describe Utils::Tar do
+RSpec.describe Utils::Tar do
   before do
     described_class.clear_executable_cache
   end
diff --git a/Library/Homebrew/test/utils/timer_spec.rb b/Library/Homebrew/test/utils/timer_spec.rb
index e2a8fb1982..2140fd28a6 100644
--- a/Library/Homebrew/test/utils/timer_spec.rb
+++ b/Library/Homebrew/test/utils/timer_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/timer"
 
-describe Utils::Timer do
+RSpec.describe Utils::Timer do
   describe "#remaining" do
     it "returns nil when nil" do
       expect(described_class.remaining(nil)).to be_nil
diff --git a/Library/Homebrew/test/utils/topological_hash_spec.rb b/Library/Homebrew/test/utils/topological_hash_spec.rb
index ef4290f967..a1bf8904e5 100644
--- a/Library/Homebrew/test/utils/topological_hash_spec.rb
+++ b/Library/Homebrew/test/utils/topological_hash_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/topological_hash"
 
-describe Utils::TopologicalHash do
+RSpec.describe Utils::TopologicalHash do
   describe "#tsort" do
     it "returns a topologically sorted array" do
       hash = described_class.new
diff --git a/Library/Homebrew/test/utils/tty_spec.rb b/Library/Homebrew/test/utils/tty_spec.rb
index c60f188e02..41672b1cfd 100644
--- a/Library/Homebrew/test/utils/tty_spec.rb
+++ b/Library/Homebrew/test/utils/tty_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-describe Tty do
+RSpec.describe Tty do
   describe "::strip_ansi" do
     it "removes ANSI escape codes from a string" do
       expect(described_class.strip_ansi("\033[36;7mhello\033[0m")).to eq("hello")
diff --git a/Library/Homebrew/test/utils/user_spec.rb b/Library/Homebrew/test/utils/user_spec.rb
index 4b01c3fd02..47fb75951f 100644
--- a/Library/Homebrew/test/utils/user_spec.rb
+++ b/Library/Homebrew/test/utils/user_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils/user"
 
-describe User do
+RSpec.describe User do
   subject { described_class.current }
 
   it { is_expected.to eq ENV.fetch("USER") }
diff --git a/Library/Homebrew/test/utils_spec.rb b/Library/Homebrew/test/utils_spec.rb
index 1ec12d645d..b8766fc9ac 100644
--- a/Library/Homebrew/test/utils_spec.rb
+++ b/Library/Homebrew/test/utils_spec.rb
@@ -2,7 +2,7 @@
 
 require "utils"
 
-describe Utils do
+RSpec.describe Utils do
   describe ".deconstantize" do
     it "removes the rightmost segment from the constant expression in the string" do
       expect(described_class.deconstantize("Net::HTTP")).to eq("Net")
diff --git a/Library/Homebrew/test/version/parser_spec.rb b/Library/Homebrew/test/version/parser_spec.rb
index 42929c164e..ce8d2861d9 100644
--- a/Library/Homebrew/test/version/parser_spec.rb
+++ b/Library/Homebrew/test/version/parser_spec.rb
@@ -2,7 +2,7 @@
 
 require "version/parser"
 
-describe Version::Parser do
+RSpec.describe Version::Parser do
   specify "::new" do
     expect { described_class.new }
       .to raise_error("Version::Parser is declared as abstract; it cannot be instantiated")
diff --git a/Library/Homebrew/test/version_spec.rb b/Library/Homebrew/test/version_spec.rb
index 7bc59b64bd..49dfad7878 100644
--- a/Library/Homebrew/test/version_spec.rb
+++ b/Library/Homebrew/test/version_spec.rb
@@ -2,7 +2,7 @@
 
 require "version"
 
-describe Version do
+RSpec.describe Version do
   subject(:version) { described_class.new("1.2.3") }
 
   specify ".formula_optionally_versioned_regex" do