audit: permit license groups

Library/Homebrew/dev-cmd/audit.rb

@@ -335,6 +335,14 @@ module Homebrew
       openssl@1.1
     ].freeze
 
+    PERMITTED_LICENSE_MISMATCHES = {
+      "AGPL-3.0" => ["AGPL-3.0-only", "AGPL-3.0-or-later"],
+      "GPL-2.0"  => ["GPL-2.0-only",  "GPL-2.0-or-later"],
+      "GPL-3.0"  => ["GPL-3.0-only",  "GPL-3.0-or-later"],
+      "LGPL-2.1" => ["LGPL-2.1-only", "LGPL-2.1-or-later"],
+      "LGPL-3.0" => ["LGPL-3.0-only", "LGPL-3.0-or-later"],
+    }.freeze
+
     def audit_license
       if formula.license.present?
         non_standard_licenses = formula.license.map do |license|
@@ -355,12 +363,12 @@ module Homebrew
 
         github_license = GitHub.get_repo_license(user, repo)
         return if github_license && (formula.license + ["NOASSERTION"]).include?(github_license)
+        return if PERMITTED_LICENSE_MISMATCHES[github_license]&.any? { |license| formula.license.include? license }
 
-        problem "License mismatch - GitHub license is: #{Array(github_license)}, "\
+        problem "Formula license #{formula.license} does not match GitHub license #{Array(github_license)}."
-                "but Formulae license states: #{formula.license}."
 
-      elsif @new_formula
+      elsif @new_formula && @core_tap
-        problem "No license specified for package."
+        problem "Formulae in homebrew/core must specify a license."
       end
     end
 

Library/Homebrew/test/dev-cmd/audit_spec.rb

@@ -102,14 +102,14 @@ module Homebrew
       end
 
       it "detects no license info" do
-        fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: true
+        fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: true, core_tap: true
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"
           end
         RUBY
 
         fa.audit_license
-        expect(fa.problems.first).to match "No license specified for package."
+        expect(fa.problems.first).to match "Formulae in homebrew/core must specify a license."
       end
 
       it "detects if license is not a standard spdx-id" do
@@ -174,6 +174,34 @@ module Homebrew
         expect(fa.problems).to be_empty
       end
 
+      it "checks online and verifies that a standard license id is in the same exempted license group"\
+        "as what is indicated on its Github repo" do
+        fa = formula_auditor "cask", <<~RUBY, spdx_data: spdx_data, online: true, new_formula: true
+          class Cask < Formula
+            url "https://github.com/cask/cask/archive/v0.8.4.tar.gz"
+            head "https://github.com/cask/cask.git"
+            license "GPL-3.0-or-later"
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems).to be_empty
+      end
+
+      it "checks online and verifies that a standard license array is in the same exempted license group"\
+        "as what is indicated on its Github repo" do
+        fa = formula_auditor "cask", <<~RUBY, spdx_data: spdx_data, online: true, new_formula: true
+          class Cask < Formula
+            url "https://github.com/cask/cask/archive/v0.8.4.tar.gz"
+            head "https://github.com/cask/cask.git"
+            license ["GPL-3.0-or-later", "MIT"]
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems).to be_empty
+      end
+
       it "checks online and detects that a formula-specified license is not "\
         "the same as what is indicated on its Github repository" do
         fa = formula_auditor "cask", <<~RUBY, online: true, spdx_data: spdx_data, core_tap: true, new_formula: true
@@ -185,8 +213,8 @@ module Homebrew
         RUBY
 
         fa.audit_license
-        expect(fa.problems.first).to match "License mismatch - GitHub license is: [\"GPL-3.0\"], "\
+        expect(fa.problems.first).to match "Formula license #{Array(standard_mismatch_spdx_id)} "\
-        "but Formulae license states: #{Array(standard_mismatch_spdx_id)}."
+                                           "does not match GitHub license [\"GPL-3.0\"]."
       end
 
       it "checks online and detects that an array of license does not contain "\
@@ -200,8 +228,8 @@ module Homebrew
         RUBY
 
         fa.audit_license
-        expect(fa.problems.first).to match "License mismatch - GitHub license is: [\"GPL-3.0\"], "\
+        expect(fa.problems.first).to match "Formula license #{license_array_mismatch} "\
-        "but Formulae license states: #{Array(license_array_mismatch)}."
+          "does not match GitHub license [\"GPL-3.0\"]."
       end
 
       it "checks online and verifies that an array of license contains "\