Merge pull request #7953 from MLH-Fellowship/license-multiple

Allow multiple licenses to be specified as an array with a consistent internal API

Library/Homebrew/dev-cmd/audit.rb

@@ -330,20 +330,28 @@ module Homebrew
 
     def audit_license
       if formula.license.present?
-        if @spdx_data["licenses"].any? { |lic| lic["licenseId"] == formula.license }
+        non_standard_licenses = []
-          return unless @online
+        formula.license.each do |license|
+          next if @spdx_data["licenses"].any? { |spdx| spdx["licenseId"] == license }
 
-          user, repo = get_repo_data(%r{https?://github\.com/([^/]+)/([^/]+)/?.*}) if @new_formula
+          non_standard_licenses << license
-          return if user.blank?
-
-          github_license = GitHub.get_repo_license(user, repo)
-          return if github_license && [formula.license, "NOASSERTION"].include?(github_license)
-
-          problem "License mismatch - GitHub license is: #{github_license}, "\
-                  "but Formulae license states: #{formula.license}."
-        else
-          problem "#{formula.license} is not a standard SPDX license."
         end
+
+        if non_standard_licenses.present?
+          problem "Formula #{formula.name} contains non-standard SPDX licenses: #{non_standard_licenses}."
+        end
+
+        return unless @online
+
+        user, repo = get_repo_data(%r{https?://github\.com/([^/]+)/([^/]+)/?.*}) if @new_formula
+        return if user.blank?
+
+        github_license = GitHub.get_repo_license(user, repo)
+        return if github_license && (formula.license + ["NOASSERTION"]).include?(github_license)
+
+        problem "License mismatch - GitHub license is: #{Array(github_license)}, "\
+                "but Formulae license states: #{formula.license}."
+
       elsif @new_formula
         problem "No license specified for package."
       end

Library/Homebrew/formula.rb

@@ -2208,9 +2208,16 @@ class Formula
     # @!attribute [w]
     # The SPDX ID of the open-source license that the formula uses.
     # Shows when running `brew info`.
-    #
+    # Multiple licenses means that the software is licensed under multiple licenses.
+    # Do not use multiple licenses if e.g. different parts are under different licenses.
     # <pre>license "BSD-2-Clause"</pre>
-    attr_rw :license
+    def license(args = nil)
+      if args.nil?
+        @licenses
+      else
+        @licenses = Array(args)
+      end
+    end
 
     # @!attribute [w] homepage
     # The homepage for the software. Used by users to get more information

Library/Homebrew/formula_installer.rb

@@ -1123,18 +1123,18 @@ class FormulaInstaller
       next if @ignore_deps
 
       dep_f = dep.to_formula
-      next unless forbidden_licenses.include? dep_f.license
+      next unless dep_f.license.all? { |license| forbidden_licenses.include? license }
 
       raise CannotInstallFormulaError, <<~EOS
-        The installation of #{formula.name} has a dependency on #{dep.name} with a forbidden license #{dep_f.license}.
+        The installation of #{formula.name} has a dependency on #{dep.name} where all its licenses are forbidden: #{dep_f.license}.
       EOS
     end
     return if @only_deps
 
-    return unless forbidden_licenses.include? formula.license
+    return unless formula.license.all? { |license| forbidden_licenses.include? license }
 
     raise CannotInstallFormulaError, <<~EOS
-      #{formula.name} has a forbidden license #{formula.license}.
+      #{formula.name}'s licenses are all forbidden: #{formula.license}.
     EOS
   end
 end

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

@@ -86,12 +86,14 @@ module Homebrew
 
       let(:custom_spdx_id) { "zzz" }
       let(:standard_mismatch_spdx_id) { "0BSD" }
+      let(:license_array) { ["0BSD", "GPL-3.0"] }
+      let(:license_array_mismatch) { ["0BSD", "MIT"] }
+      let(:license_array_nonstandard) { ["0BSD", "zzz", "MIT"] }
 
       it "does not check if the formula is not a new formula" do
         fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: false
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"
-            license ""
           end
         RUBY
 
@@ -103,7 +105,6 @@ module Homebrew
         fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: true
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"
-            license ""
           end
         RUBY
 
@@ -120,7 +121,19 @@ module Homebrew
         RUBY
 
         fa.audit_license
-        expect(fa.problems.first).to match "#{custom_spdx_id} is not a standard SPDX license."
+        expect(fa.problems.first).to match "Formula foo contains non-standard SPDX licenses: [\"zzz\"]."
+      end
+
+      it "detects if license array contains a non-standard spdx-id" do
+        fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: true
+          class Foo < Formula
+            url "https://brew.sh/foo-1.0.tgz"
+            license #{license_array_nonstandard}
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems.first).to match "Formula foo contains non-standard SPDX licenses: [\"zzz\"]."
       end
 
       it "verifies that a license info is a standard spdx id" do
@@ -135,6 +148,18 @@ module Homebrew
         expect(fa.problems).to be_empty
       end
 
+      it "verifies that a license array contains only standard spdx id" do
+        fa = formula_auditor "foo", <<~RUBY, spdx_data: spdx_data, new_formula: true
+          class Foo < Formula
+            url "https://brew.sh/foo-1.0.tgz"
+            license #{license_array}
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems).to be_empty
+      end
+
       it "checks online and verifies that a standard license id is the same "\
         "as what is indicated on its Github repo" do
         fa = formula_auditor "cask", <<~RUBY, spdx_data: spdx_data, online: true, core_tap: true, new_formula: true
@@ -160,8 +185,37 @@ 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 "License mismatch - GitHub license is: [\"GPL-3.0\"], "\
-        "but Formulae license states: #{standard_mismatch_spdx_id}."
+        "but Formulae license states: #{Array(standard_mismatch_spdx_id)}."
+      end
+
+      it "checks online and detects that an array of license does not contain "\
+        "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
+          class Cask < Formula
+            url "https://github.com/cask/cask/archive/v0.8.4.tar.gz"
+            head "https://github.com/cask/cask.git"
+            license #{license_array_mismatch}
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems.first).to match "License mismatch - GitHub license is: [\"GPL-3.0\"], "\
+        "but Formulae license states: #{Array(license_array_mismatch)}."
+      end
+
+      it "checks online and verifies that an array of license contains "\
+        "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
+          class Cask < Formula
+            url "https://github.com/cask/cask/archive/v0.8.4.tar.gz"
+            head "https://github.com/cask/cask.git"
+            license #{license_array}
+          end
+        RUBY
+
+        fa.audit_license
+        expect(fa.problems).to be_empty
       end
     end