Fix bug with running bin/codeownership validate when a GitHub team ha…

…s changed (#57)

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    code_ownership (1.32.11)
+    code_ownership (1.32.12)
       code_teams (~> 1.0)
       packs
       sorbet-runtime

code_ownership.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = 'code_ownership'
-  spec.version       = '1.32.11'
+  spec.version       = '1.32.12'
   spec.authors       = ['Gusto Engineers']
   spec.email         = ['[email protected]']
   spec.summary       = 'A gem to help engineering teams declare ownership of code'

lib/code_ownership/private/codeowners_file.rb

@@ -135,6 +135,12 @@ def self.to_glob_cache
             # This will skip over lines that are not of the correct form
             next if split_line.count > 2
             entry, github_team = split_line
+            code_team = github_team_to_code_team_map[T.must(github_team)]
+            # If a GitHub team is changed and a user runs `bin/codeownership validate`, we won't be able to identify
+            # what team is associated with the removed github team.
+            # Therefore, if we can't determine the team, we just skip it.
+            # This affects how complete the cache is, but that will still be caught by `bin/codeownership validate`.
+            next if code_team.nil?
             raw_cache_contents[current_mapper] ||= {}
             raw_cache_contents.fetch(current_mapper)[T.must(entry)] = github_team_to_code_team_map.fetch(T.must(github_team))
           end

spec/lib/code_ownership/private/validations/github_codeowners_up_to_date_spec.rb

@@ -475,6 +475,57 @@ module CodeOwnership
             expect { CodeOwnership.validate!(autocorrect: false) }.to_not raise_error
           end
         end
+
+        context 'in an application with a CODEOWNERS file that has a reference to a github team that no longer exists' do
+          before do
+            write_configuration
+
+            write_file('packs/my_pack/owned_file.rb', <<~CONTENTS)
+              # @team Bar
+            CONTENTS
+
+            write_file('config/teams/bar.yml', <<~CONTENTS)
+              name: Bar
+              github:
+                team: '@MyOrg/bar-team'
+            CONTENTS
+          end
+
+          it 'prints out the diff' do
+            FileUtils.mkdir('.github')
+            codeowners_path.write <<~CODEOWNERS
+              # STOP! - DO NOT EDIT THIS FILE MANUALLY
+              # This file was automatically generated by "bin/codeownership validate".
+              #
+              # CODEOWNERS is used for GitHub to suggest code/file owners to various GitHub
+              # teams. This is useful when developers create Pull Requests since the
+              # code/file owner is notified. Reference GitHub docs for more details:
+              # https://help.github.com/en/articles/about-code-owners
+
+
+              # Annotations at the top of file
+              /packs/my_pack/owned_file.rb @MyOrg/this-team-does-not-exist
+            CODEOWNERS
+
+            expect_any_instance_of(codeowners_validation).to_not receive(:`) # rubocop:disable RSpec/AnyInstance
+            expect { CodeOwnership.validate!(autocorrect: false) }.to raise_error do |e|
+              expect(e).to be_a CodeOwnership::InvalidCodeOwnershipConfigurationError
+              expect(e.message).to eq <<~EXPECTED.chomp
+                CODEOWNERS out of date. Run `bin/codeownership validate` to update the CODEOWNERS file
+
+                CODEOWNERS should contain the following lines, but does not:
+                - "/packs/my_pack/owned_file.rb @MyOrg/bar-team"
+                - "# Team YML ownership"
+                - "/config/teams/bar.yml @MyOrg/bar-team"
+
+                CODEOWNERS should not contain the following lines, but it does:
+                - "/packs/my_pack/owned_file.rb @MyOrg/this-team-does-not-exist"
+
+                See https://github.com/rubyatscale/code_ownership#README.md for more details
+              EXPECTED
+            end
+          end
+        end
       end
 
       context 'code_ownership.yml has skip_codeowners_validation set' do