Add a SystemNoteService class

There's a lot of code in the Note model that only deals with creating
system notes, so we're going to split that into its own class.

1 files changed, 353 insertions, 0 deletions

diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
new file mode 100644
index 00000000000..cda4e7698f1
--- /dev/null
+++ b/spec/services/system_note_service_spec.rb
@@ -0,0 +1,353 @@
+require 'spec_helper'
+
+describe SystemNoteService do
+  let(:project)  { create(:project) }
+  let(:author)   { create(:user) }
+  let(:noteable) { create(:issue, project: project) }
+
+  shared_examples_for 'a system note' do
+    it 'sets the noteable model' do
+      expect(subject.noteable).to eq noteable
+    end
+
+    it 'sets the project' do
+      expect(subject.project).to eq project
+    end
+
+    it 'sets the author' do
+      expect(subject.author).to eq author
+    end
+
+    it 'is a system note' do
+      expect(subject).to be_system
+    end
+  end
+
+  describe '.assignee_change' do
+    let(:assignee) { create(:user) }
+
+    subject { described_class.assignee_change(noteable, project, author, assignee) }
+
+    it_behaves_like 'a system note'
+
+    context 'when assignee added' do
+      it 'sets the note text' do
+        expect(subject.note).to eq "Reassigned to @#{assignee.username}"
+      end
+    end
+
+    context 'when assignee removed' do
+      let(:assignee) { nil }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq 'Assignee removed'
+      end
+    end
+  end
+
+  describe '.cross_reference' do
+    let(:mentioner) { create(:issue, project: project) }
+
+    subject { described_class.cross_reference(noteable, mentioner, author) }
+
+    it_behaves_like 'a system note'
+
+    context 'when cross-reference disallowed' do
+      before do
+        expect(described_class).to receive(:cross_reference_disallowed?).and_return(true)
+      end
+
+      it 'returns nil' do
+        expect(subject).to be_nil
+      end
+    end
+
+    context 'when cross-reference allowed' do
+      before do
+        expect(described_class).to receive(:cross_reference_disallowed?).and_return(false)
+      end
+
+      describe 'note_body' do
+        context 'cross-project' do
+          let(:project2)  { create(:project) }
+          let(:mentioner) { create(:issue, project: project2) }
+
+          context 'from Commit' do
+            let(:mentioner) { project2.repository.commit }
+
+            it 'references the mentioning commit' do
+              expect(subject.note).to eq "mentioned in commit #{project2.path_with_namespace}@#{mentioner.id}"
+            end
+          end
+
+          context 'from non-Commit' do
+            it 'references the mentioning object' do
+              expect(subject.note).to eq "mentioned in issue #{project2.path_with_namespace}##{mentioner.iid}"
+            end
+          end
+        end
+
+        context 'same project' do
+          context 'from Commit' do
+            let(:mentioner) { project.repository.commit }
+
+            it 'references the mentioning commit' do
+              expect(subject.note).to eq "mentioned in commit #{mentioner.id}"
+            end
+          end
+
+          context 'from non-Commit' do
+            it 'references the mentioning object' do
+              expect(subject.note).to eq "mentioned in issue ##{mentioner.iid}"
+            end
+          end
+        end
+      end
+    end
+  end
+
+  describe '.label_change' do
+    let(:labels)  { create_list(:label, 2) }
+    let(:added)   { [] }
+    let(:removed) { [] }
+
+    subject { described_class.label_change(noteable, project, author, added, removed) }
+
+    it_behaves_like 'a system note'
+
+    context 'with added labels' do
+      let(:added)   { labels }
+      let(:removed) { [] }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq "Added ~#{labels[0].id} ~#{labels[1].id} labels"
+      end
+    end
+
+    context 'with removed labels' do
+      let(:added)   { [] }
+      let(:removed) { labels }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq "Removed ~#{labels[0].id} ~#{labels[1].id} labels"
+      end
+    end
+
+    context 'with added and removed labels' do
+      let(:added)   { [labels[0]] }
+      let(:removed) { [labels[1]] }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq "Added ~#{labels[0].id} and removed ~#{labels[1].id} labels"
+      end
+    end
+  end
+
+  describe '.milestone_change' do
+    let(:milestone) { create(:milestone, project: project) }
+
+    subject { described_class.milestone_change(noteable, project, author, milestone) }
+
+    it_behaves_like 'a system note'
+
+    context 'when milestone added' do
+      it 'sets the note text' do
+        expect(subject.note).to eq "Milestone changed to #{milestone.title}"
+      end
+    end
+
+    context 'when milestone removed' do
+      let(:milestone) { nil }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq 'Milestone removed'
+      end
+    end
+  end
+
+  describe '.commit_add' do
+    let(:noteable)    { create(:merge_request, source_project: project) }
+    let(:new_commits) { noteable.commits }
+    let(:old_commits) { [] }
+    let(:oldrev)      { nil }
+
+    subject { described_class.commit_add(noteable, project, author, new_commits, old_commits, oldrev) }
+
+    it_behaves_like 'a system note'
+
+    describe 'note body' do
+      let(:note_lines) { subject.note.split("\n").reject(&:blank?) }
+
+      context 'without existing commits' do
+        it 'adds a message header' do
+          expect(note_lines[0]).to eq "Added #{new_commits.size} commits:"
+        end
+
+        it 'adds a message line for each commit' do
+          new_commits.each_with_index do |commit, i|
+            # Skip the header
+            expect(note_lines[i + 1]).to eq "* #{commit.short_id} - #{commit.title}"
+          end
+        end
+      end
+
+      describe 'summary line for existing commits' do
+        let(:summary_line) { note_lines[1] }
+
+        context 'with one existing commit' do
+          let(:old_commits) { [noteable.commits.last] }
+
+          it 'includes the existing commit' do
+            expect(summary_line).to eq "* #{old_commits.first.short_id} - 1 commit from branch `feature`"
+          end
+        end
+
+        context 'with multiple existing commits' do
+          let(:old_commits) { noteable.commits[3..-1] }
+
+          context 'with oldrev' do
+            let(:oldrev) { noteable.commits[2].id }
+
+            it 'includes a commit range' do
+              expect(summary_line).to start_with "* #{Commit.truncate_sha(oldrev)}...#{old_commits.last.short_id}"
+            end
+
+            it 'includes a commit count' do
+              expect(summary_line).to end_with " - 2 commits from branch `feature`"
+            end
+          end
+
+          context 'without oldrev' do
+            it 'includes a commit range' do
+              expect(summary_line).to start_with "* #{old_commits[0].short_id}..#{old_commits[-1].short_id}"
+            end
+
+            it 'includes a commit count' do
+              expect(summary_line).to end_with " - 2 commits from branch `feature`"
+            end
+          end
+
+          context 'on a fork' do
+            before do
+              expect(noteable).to receive(:for_fork?).and_return(true)
+            end
+
+            it 'includes the project namespace' do
+              expect(summary_line).to end_with "`#{noteable.target_project_namespace}:feature`"
+            end
+          end
+        end
+      end
+    end
+  end
+
+  describe '.status_change' do
+    let(:status) { 'new_status' }
+    let(:source) { nil }
+
+    subject { described_class.status_change(noteable, project, author, status, source) }
+
+    it_behaves_like 'a system note'
+
+    context 'with a source' do
+      let(:source) { double('commit', gfm_reference: 'commit 123456') }
+
+      it 'sets the note text' do
+        expect(subject.note).to eq "Status changed to #{status} by commit 123456"
+      end
+    end
+
+    context 'without a source' do
+      it 'sets the note text' do
+        expect(subject.note).to eq "Status changed to #{status}"
+      end
+    end
+  end
+
+  describe '.cross_reference?' do
+    it 'is truthy when text begins with expected text' do
+      expect(described_class.cross_reference?('mentioned in issue #1')).to be_truthy
+    end
+
+    it 'is falsey when text does not begin with expected text' do
+      expect(described_class.cross_reference?('this is a note')).to be_falsey
+    end
+  end
+
+  describe '.cross_reference_disallowed?'
+
+  describe '.cross_reference_exists?' do
+    let(:commit0) { project.commit }
+    let(:commit1) { project.commit('HEAD~2') }
+
+    context 'issue from commit' do
+      before do
+        # Mention issue (noteable) from commit0
+        described_class.cross_reference(noteable, commit0, author)
+      end
+
+      it 'is truthy when already mentioned' do
+        expect(described_class.cross_reference_exists?(noteable, commit0)).
+          to be_truthy
+      end
+
+      it 'is falsey when not already mentioned' do
+        expect(described_class.cross_reference_exists?(noteable, commit1)).
+          to be_falsey
+      end
+    end
+
+    context 'commit from commit' do
+      before do
+        # Mention commit1 from commit0
+        described_class.cross_reference(commit0, commit1, author)
+      end
+
+      it 'is truthy when already mentioned' do
+        expect(described_class.cross_reference_exists?(commit0, commit1)).
+          to be_truthy
+      end
+
+      it 'is falsey when not already mentioned' do
+        expect(described_class.cross_reference_exists?(commit1, commit0)).
+          to be_falsey
+      end
+    end
+
+    context 'legacy note with Markdown emphasis' do
+      let(:mentioner) { create(:issue, project: project) }
+
+      before do
+        note = "_mentioned in issue ##{mentioner.iid}_"
+        create(:system_note, noteable: noteable, note: note, project: project)
+      end
+
+      it 'detects if a mentionable with emphasis has been mentioned' do
+        expect(described_class.cross_reference_exists?(noteable, mentioner)).
+          to be_truthy
+      end
+
+      context 'when referenced project has underscores' do
+        let(:project)  { create(:empty_project, path: 'first_project') }
+        let(:project2) { create(:empty_project, path: 'second_project') }
+
+        let(:issue)  { mentioner }
+        let(:issue2) { create(:issue, project: project2) }
+
+        before do
+          described_class.cross_reference(issue, issue2, author)
+        end
+
+        it 'is truthy when already mentioned' do
+          expect(described_class.cross_reference_exists?(issue, issue2)).
+            to be_truthy
+        end
+
+        it 'is falsey when not already mentioned' do
+          expect(described_class.cross_reference_exists?(issue2, issue)).
+            to be_falsey
+        end
+      end
+    end
+  end
+end