Unfold references for group labels when moving issue to another project

app/helpers/labels_helper.rb

@@ -115,8 +115,8 @@ module LabelsHelper
     span.html_safe
   end
 
-  def render_colored_cross_project_label(label, tooltip: true)
-    label_suffix = label.project.name_with_namespace
+  def render_colored_cross_project_label(label, source_project = nil, tooltip: true)
+    label_suffix = source_project ? source_project.name_with_namespace : label.project.name_with_namespace
     label_suffix = " <i>in #{escape_once(label_suffix)}</i>"
     render_colored_label(label, label_suffix, tooltip: tooltip)
   end

app/models/group_label.rb

@@ -2,4 +2,21 @@ class GroupLabel < Label
   belongs_to :group
 
   validates :group, presence: true
+
+  ##
+  # Returns the String necessary to reference this GroupLabel in Markdown
+  #
+  # format - Symbol format to use (default: :id, optional: :name)
+  #
+  # Examples:
+  #
+  #   GroupLabel.first.to_reference                # => "~1"
+  #   GroupLabel.first.to_reference(format: :name) # => "~\"bug\""
+  #
+  # Returns a String
+  #
+  def to_reference(from_project = nil, format: :id)
+    format_reference = label_format_reference(format)
+    "#{self.class.reference_prefix}#{format_reference}"
+  end
 end

app/models/label.rb

@@ -73,30 +73,6 @@ class Label < ActiveRecord::Base
     nil
   end
 
-  ##
-  # Returns the String necessary to reference this Label in Markdown
-  #
-  # format - Symbol format to use (default: :id, optional: :name)
-  #
-  # Examples:
-  #
-  #   Label.first.to_reference                # => "~1"
-  #   Label.first.to_reference(format: :name) # => "~\"bug\""
-  #   Label.first.to_reference(project)       # => "gitlab-org/gitlab-ce~1"
-  #
-  # Returns a String
-  #
-  def to_reference(from_project = nil, format: :id)
-    format_reference = label_format_reference(format)
-    reference = "#{self.class.reference_prefix}#{format_reference}"
-
-    if cross_project_reference?(from_project)
-      project.to_reference + reference
-    else
-      reference
-    end
-  end
-
   def open_issues_count(user = nil, project = nil)
     issues_count(user, project_id: project.try(:id) || project_id, state: 'opened')
   end

app/models/project_label.rb

@@ -7,6 +7,30 @@ class ProjectLabel < Label
 
   delegate :group, to: :project, allow_nil: true
 
+  ##
+  # Returns the String necessary to reference this ProjectLabel in Markdown
+  #
+  # format - Symbol format to use (default: :id, optional: :name)
+  #
+  # Examples:
+  #
+  #   ProjectLabel.first.to_reference                # => "~1"
+  #   ProjectLabel.first.to_reference(format: :name) # => "~\"bug\""
+  #   ProjectLabel.first.to_reference(project)       # => "gitlab-org/gitlab-ce~1"
+  #
+  # Returns a String
+  #
+  def to_reference(from_project = nil, format: :id)
+    format_reference = label_format_reference(format)
+    reference = "#{self.class.reference_prefix}#{format_reference}"
+
+    if cross_project_reference?(from_project)
+      project.to_reference + reference
+    else
+      reference
+    end
+  end
+
   private
 
   def title_must_not_exist_at_group_level

lib/banzai/filter/label_reference_filter.rb

@@ -70,11 +70,44 @@ module Banzai
       end
 
       def object_link_text(object, matches)
-        if object.is_a?(GroupLabel) || object.project == context[:project]
+        if same_group?(object) && namespace_match?(matches)
+          render_same_project_label(object)
+        elsif same_project?(object)
+          render_same_project_label(object)
+        else
+          render_cross_project_label(object, matches)
+        end
+      end
+
+      def same_group?(object)
+        object.is_a?(GroupLabel) && object.group == project.group
+      end
+
+      def namespace_match?(matches)
+        matches[:project].blank? || matches[:project] == project.path_with_namespace
+      end
+
+      def same_project?(object)
+        object.is_a?(ProjectLabel) && object.project == project
+      end
+
+      def project
+        context[:project]
+      end
+
+      def render_same_project_label(object)
         LabelsHelper.render_colored_label(object)
+      end
+
+      def render_cross_project_label(object, matches)
+        source_project =
+          if matches[:project]
+            Project.find_with_namespace(matches[:project])
           else
-          LabelsHelper.render_colored_cross_project_label(object)
+            object.project
           end
+
+        LabelsHelper.render_colored_cross_project_label(object, source_project)
       end
 
       def unescape_html_entities(text)

lib/gitlab/gfm/reference_rewriter.rb

@@ -58,7 +58,7 @@ module Gitlab
         referable = find_referable(reference)
         return reference unless referable
 
-        cross_reference = referable.to_reference(target_project)
+        cross_reference = build_cross_reference(referable, target_project)
         return reference if reference == cross_reference
 
         new_text = before + cross_reference + after
@@ -72,6 +72,22 @@ module Gitlab
         extractor.all.first
       end
 
+      def build_cross_reference(referable, target_project)
+        if referable.respond_to?(:project)
+          referable.to_reference(target_project)
+        else
+          to_reference(referable, target_project)
+        end
+      end
+
+      def to_reference(referable, target_project)
+        if @source_project != target_project
+          @source_project.to_reference + referable.to_reference
+        else
+          referable.to_reference
+        end
+      end
+
       def substitution_valid?(substituted)
         @original_html == markdown(substituted)
       end

spec/lib/banzai/filter/label_reference_filter_spec.rb

@@ -305,6 +305,58 @@ describe Banzai::Filter::LabelReferenceFilter, lib: true do
     end
   end
 
+  describe 'group label references' do
+    let(:group)       { create(:group) }
+    let(:project)     { create(:empty_project, :public, namespace: group) }
+    let(:group_label) { create(:group_label, name: 'gfm references', group: group) }
+
+    context 'without project reference' do
+      let(:reference) { group_label.to_reference(format: :name) }
+
+      it 'links to a valid reference' do
+        doc = reference_filter("See #{reference}", project: project)
+
+        expect(doc.css('a').first.attr('href')).to eq urls.
+          namespace_project_issues_url(project.namespace, project, label_name: group_label.name)
+        expect(doc.text).to eq 'See gfm references'
+      end
+
+      it 'links with adjacent text' do
+        doc = reference_filter("Label (#{reference}.)")
+        expect(doc.to_html).to match(%r(\(<a.+><span.+>#{group_label.name}</span></a>\.\)))
+      end
+
+      it 'ignores invalid label names' do
+        exp = act = %(Label #{Label.reference_prefix}"#{group_label.name.reverse}")
+
+        expect(reference_filter(act).to_html).to eq exp
+      end
+    end
+
+    context 'with project reference' do
+      let(:reference) { project.to_reference + group_label.to_reference(format: :name) }
+
+      it 'links to a valid reference' do
+        doc = reference_filter("See #{reference}", project: project)
+
+        expect(doc.css('a').first.attr('href')).to eq urls.
+          namespace_project_issues_url(project.namespace, project, label_name: group_label.name)
+        expect(doc.text).to eq 'See gfm references'
+      end
+
+      it 'links with adjacent text' do
+        doc = reference_filter("Label (#{reference}.)")
+        expect(doc.to_html).to match(%r(\(<a.+><span.+>#{group_label.name}</span></a>\.\)))
+      end
+
+      it 'ignores invalid label names' do
+        exp = act = %(Label #{project.to_reference}#{Label.reference_prefix}"#{group_label.name.reverse}")
+
+        expect(reference_filter(act).to_html).to eq exp
+      end
+    end
+  end
+
   describe 'cross project label references' do
     context 'valid project referenced' do
       let(:another_project)  { create(:empty_project, :public) }
@@ -339,4 +391,34 @@ describe Banzai::Filter::LabelReferenceFilter, lib: true do
       end
     end
   end
+
+  describe 'cross group label references' do
+    context 'valid project referenced' do
+      let(:group) { create(:group) }
+      let(:project) { create(:empty_project, :public, namespace: group) }
+      let(:another_group) { create(:group) }
+      let(:another_project)  { create(:empty_project, :public, namespace: another_group) }
+      let(:project_name) { another_project.name_with_namespace }
+      let(:group_label) { create(:group_label, group: another_group, color: '#00ff00') }
+      let(:reference) { another_project.to_reference + group_label.to_reference }
+
+      let!(:result) { reference_filter("See #{reference}", project: project) }
+
+      it 'points to referenced project issues page' do
+        expect(result.css('a').first.attr('href'))
+          .to eq urls.namespace_project_issues_url(another_project.namespace,
+                                                   another_project,
+                                                   label_name: group_label.name)
+      end
+
+      it 'has valid color' do
+        expect(result.css('a span').first.attr('style'))
+          .to match /background-color: #00ff00/
+      end
+
+      it 'contains cross project content' do
+        expect(result.css('a').first.text).to eq "#{group_label.name} in #{project_name}"
+      end
+    end
+  end
 end

spec/lib/gitlab/gfm/reference_rewriter_spec.rb

@@ -2,8 +2,8 @@ require 'spec_helper'
 
 describe Gitlab::Gfm::ReferenceRewriter do
   let(:text) { 'some text' }
-  let(:old_project) { create(:project) }
-  let(:new_project) { create(:project) }
+  let(:old_project) { create(:project, name: 'old') }
+  let(:new_project) { create(:project, name: 'new') }
   let(:user) { create(:user) }
 
   before { old_project.team << [user, :guest] }
@@ -62,7 +62,7 @@ describe Gitlab::Gfm::ReferenceRewriter do
           it { is_expected.to eq "#{ref}, `#1`, #{ref}, `#1`" }
         end
 
-        context 'description with labels' do
+        context 'description with project labels' do
           let!(:label) { create(:label, id: 123, name: 'test', project: old_project) }
           let(:project_ref) { old_project.to_reference }
 
@@ -76,6 +76,26 @@ describe Gitlab::Gfm::ReferenceRewriter do
             it { is_expected.to eq %Q{#{project_ref}#1 and #{project_ref}~123} }
           end
         end
+
+        context 'description with group labels' do
+          let(:old_group) { create(:group) }
+          let!(:group_label) { create(:group_label, id: 321, name: 'group label', group: old_group) }
+          let(:project_ref) { old_project.to_reference }
+
+          before do
+            old_project.update(namespace: old_group)
+          end
+
+          context 'label referenced by id' do
+            let(:text) { '#1 and ~321' }
+            it { is_expected.to eq %Q{#{project_ref}#1 and #{project_ref}~321} }
+          end
+
+          context 'label referenced by text' do
+            let(:text) { '#1 and ~"group label"' }
+            it { is_expected.to eq %Q{#{project_ref}#1 and #{project_ref}~321} }
+          end
+        end
       end
 
       context 'reference contains milestone' do

spec/models/group_label_spec.rb

@@ -8,4 +8,32 @@ describe GroupLabel, models: true do
   describe 'validations' do
     it { is_expected.to validate_presence_of(:group) }
   end
+
+  describe '#to_reference' do
+    let(:label) { create(:group_label) }
+
+    context 'using id' do
+      it 'returns a String reference to the object' do
+        expect(label.to_reference).to eq "~#{label.id}"
+      end
+    end
+
+    context 'using name' do
+      it 'returns a String reference to the object' do
+        expect(label.to_reference(format: :name)).to eq %(~"#{label.name}")
+      end
+
+      it 'uses id when name contains double quote' do
+        label = create(:label, name: %q{"irony"})
+        expect(label.to_reference(format: :name)).to eq "~#{label.id}"
+      end
+    end
+
+    context 'using invalid format' do
+      it 'raises error' do
+        expect { label.to_reference(format: :invalid) }
+          .to raise_error StandardError, /Unknown format/
+      end
+    end
+  end
 end

spec/models/label_spec.rb

@@ -45,50 +45,4 @@ describe Label, models: true do
       expect(label.title).to eq('foo & bar?')
     end
   end
-
-  describe '#to_reference' do
-    let(:label) { create(:label) }
-
-    context 'using id' do
-      it 'returns a String reference to the object' do
-        expect(label.to_reference).to eq "~#{label.id}"
-      end
-    end
-
-    context 'using name' do
-      it 'returns a String reference to the object' do
-        expect(label.to_reference(format: :name)).to eq %(~"#{label.name}")
-      end
-
-      it 'uses id when name contains double quote' do
-        label = create(:label, name: %q{"irony"})
-        expect(label.to_reference(format: :name)).to eq "~#{label.id}"
-      end
-    end
-
-    context 'using invalid format' do
-      it 'raises error' do
-        expect { label.to_reference(format: :invalid) }
-          .to raise_error StandardError, /Unknown format/
-      end
-    end
-
-    context 'cross project reference' do
-      let(:project) { create(:project) }
-
-      context 'using name' do
-        it 'returns cross reference with label name' do
-          expect(label.to_reference(project, format: :name))
-            .to eq %Q(#{label.project.to_reference}~"#{label.name}")
-        end
-      end
-
-      context 'using id' do
-        it 'returns cross reference with label id' do
-          expect(label.to_reference(project, format: :id))
-            .to eq %Q(#{label.project.to_reference}~#{label.id})
-        end
-      end
-    end
-  end
 end

spec/models/project_label_spec.rb

@@ -42,4 +42,50 @@ describe ProjectLabel, models: true do
       end
     end
   end
+
+  describe '#to_reference' do
+    let(:label) { create(:label) }
+
+    context 'using id' do
+      it 'returns a String reference to the object' do
+        expect(label.to_reference).to eq "~#{label.id}"
+      end
+    end
+
+    context 'using name' do
+      it 'returns a String reference to the object' do
+        expect(label.to_reference(format: :name)).to eq %(~"#{label.name}")
+      end
+
+      it 'uses id when name contains double quote' do
+        label = create(:label, name: %q{"irony"})
+        expect(label.to_reference(format: :name)).to eq "~#{label.id}"
+      end
+    end
+
+    context 'using invalid format' do
+      it 'raises error' do
+        expect { label.to_reference(format: :invalid) }
+          .to raise_error StandardError, /Unknown format/
+      end
+    end
+
+    context 'cross project reference' do
+      let(:project) { create(:project) }
+
+      context 'using name' do
+        it 'returns cross reference with label name' do
+          expect(label.to_reference(project, format: :name))
+            .to eq %Q(#{label.project.to_reference}~"#{label.name}")
+        end
+      end
+
+      context 'using id' do
+        it 'returns cross reference with label id' do
+          expect(label.to_reference(project, format: :id))
+            .to eq %Q(#{label.project.to_reference}~#{label.id})
+        end
+      end
+    end
+  end
 end