Vendor SafeNavigationWithBlank cop

Library/.rubocop.yml

@@ -2,7 +2,6 @@
 require:
   - ./Homebrew/rubocops.rb
   - rubocop-performance
-  - rubocop-rails
   - rubocop-rspec
   - rubocop-sorbet
 
@@ -54,8 +53,8 @@ Homebrew:
 Homebrew/Blank:
   Exclude:
     # Core extensions are not available here:
-    - "Homebrew/rubocops/**/*"
     - "Homebrew/startup/bootsnap.rb"
+
 Homebrew/CompactBlank:
   Exclude:
     # `blank?` is not necessarily available here:
@@ -210,19 +209,6 @@ Performance/CaseWhenSplat:
 Performance/MethodObjectAsBlock:
   Enabled: false
 
-Rails:
-  # Selectively enable what we want.
-  Enabled: false
-  Exclude:
-    # This file is loaded before any extra methods are defined.
-    - "Homebrew/standalone/init.rb"
-    # Do not use ActiveSupport in RuboCops.
-    - "Homebrew/rubocops/**/*"
-
-# These relate to ActiveSupport and not other parts of Rails.
-Rails/SafeNavigationWithBlank:
-  Enabled: true
-
 # Intentionally disabled as it doesn't fit with our code style.
 RSpec/AnyInstance:
   Enabled: false
@@ -368,8 +354,6 @@ Style/InvertibleUnlessCondition:
     :==: :!=
     # Unset this (prefer `unless a.zero?` over `if a.nonzero?`)
     :zero?:
-    # Don't require non-standard `exclude?` (for now at least) - it's not available in every file
-    :include?:
     :blank?: :present?
 
 Style/MutableConstant:

Library/Homebrew/rubocops/all.rb

@@ -2,12 +2,14 @@
 # frozen_string_literal: true
 
 require_relative "../extend/array"
+require_relative "../extend/blank"
 require_relative "blank"
 require_relative "compact_blank"
 require_relative "io_read"
 require_relative "move_to_extend_os"
 require_relative "presence"
 require_relative "present"
+require_relative "safe_navigation_with_blank"
 require_relative "shell_commands"
 
 # formula audit cops

Library/Homebrew/rubocops/dependency_order.rb

@@ -75,7 +75,7 @@ module RuboCop
             ordered.each_with_index do |dep, pos|
               idx = pos+1
               match_nodes = build_with_dependency_name(dep)
-              next if !match_nodes || match_nodes.empty?
+              next if match_nodes.blank?
 
               idx1 = pos
               ordered.drop(idx1+1).each_with_index do |dep2, pos2|

Library/Homebrew/rubocops/safe_navigation_with_blank.rb

@@ -0,0 +1,51 @@
+# typed: true
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Homebrew
+      # Checks to make sure safe navigation isn't used with `blank?` in
+      # a conditional.
+      #
+      # @note
+      #   While the safe navigation operator is generally a good idea, when
+      #   checking `foo&.blank?` in a conditional, `foo` being `nil` will actually
+      #   do the opposite of what the author intends.
+      #
+      #   For example:
+      #
+      #   [source,ruby]
+      #   ----
+      #   foo&.blank? #=> nil
+      #   foo.blank? #=> true
+      #   ----
+      #
+      # @example
+      #   # bad
+      #   do_something if foo&.blank?
+      #   do_something unless foo&.blank?
+      #
+      #   # good
+      #   do_something if foo.blank?
+      #   do_something unless foo.blank?
+      #
+      class SafeNavigationWithBlank < Base
+        extend AutoCorrector
+
+        MSG = "Avoid calling `blank?` with the safe navigation operator in conditionals."
+
+        def_node_matcher :safe_navigation_blank_in_conditional?, <<~PATTERN
+          (if $(csend ... :blank?) ...)
+        PATTERN
+
+        def on_if(node)
+          return unless safe_navigation_blank_in_conditional?(node)
+
+          add_offense(node) do |corrector|
+            corrector.replace(safe_navigation_blank_in_conditional?(node).location.dot, ".")
+          end
+        end
+      end
+    end
+  end
+end

Library/Homebrew/test/rubocops/safe_navigation_with_blank_spec.rb

@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require "rubocops/safe_navigation_with_blank"
+
+RSpec.describe RuboCop::Cop::Homebrew::SafeNavigationWithBlank, :config do
+  context "when in a conditional" do
+    it "registers an offense on a single conditional" do
+      expect_offense(<<~RUBY)
+        do_something unless foo&.blank?
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid calling `blank?` with the safe navigation operator in conditionals.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        do_something unless foo.blank?
+      RUBY
+    end
+
+    it "registers an offense on chained conditionals" do
+      expect_offense(<<~RUBY)
+        do_something unless foo&.bar&.blank?
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Avoid calling `blank?` with the safe navigation operator in conditionals.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        do_something unless foo&.bar.blank?
+      RUBY
+    end
+
+    it "does not register an offense on `.blank?`" do
+      expect_no_offenses(<<~RUBY)
+        return if foo.blank?
+      RUBY
+    end
+  end
+
+  context "when outside a conditional" do
+    it "registers no offense" do
+      expect_no_offenses(<<~RUBY)
+        bar = foo&.blank?
+      RUBY
+    end
+  end
+end