Filter by `None`/`Any` for labels in issues/mrs API

By using the parameters `?labels=None|Any` the user can filter
issues/mrs from the API that has `none/any` label.

Affected endpoints are:

- /api/issues
- /api/projects/:id/issues
- /api/groups/:id/issues
- /api/merge_requests
- /api/projects/:id/merge_requests
- /api/groups/:id/merge_requests

1 files changed, 34 insertions, 2 deletions

diff --git a/spec/finders/issues_finder_spec.rb b/spec/finders/issues_finder_spec.rb
index c0488c83bd8..515f6f70b99 100644
--- a/spec/finders/issues_finder_spec.rb
+++ b/spec/finders/issues_finder_spec.rb
@@ -256,19 +256,51 @@ describe IssuesFinder do
           create(:label_link, label: label2, target: issue2)
         end
 
-        it 'returns the unique issues with any of those labels' do
+        it 'returns the unique issues with all those labels' do
+          expect(issues).to contain_exactly(issue2)
+        end
+      end
+
+      context 'filtering by a label that includes any or none in the title' do
+        let(:params) { { label_name: [label.title, label2.title].join(',') } }
+        let(:label) { create(:label, title: 'any foo', project: project2) }
+        let(:label2) { create(:label, title: 'bar none', project: project2) }
+
+        it 'returns the unique issues with all those labels' do
+          create(:label_link, label: label2, target: issue2)
+
           expect(issues).to contain_exactly(issue2)
         end
       end
 
       context 'filtering by no label' do
-        let(:params) { { label_name: Label::None.title } }
+        let(:params) { { label_name: described_class::FILTER_NONE } }
 
         it 'returns issues with no labels' do
           expect(issues).to contain_exactly(issue1, issue3, issue4)
         end
       end
 
+      context 'filtering by legacy No+Label' do
+        let(:params) { { label_name: Label::NONE } }
+
+        it 'returns issues with no labels' do
+          expect(issues).to contain_exactly(issue1, issue3, issue4)
+        end
+      end
+
+      context 'filtering by any label' do
+        let(:params) { { label_name: described_class::FILTER_ANY } }
+
+        it 'returns issues that have one or more label' do
+          2.times do
+            create(:label_link, label: create(:label, project: project2), target: issue3)
+          end
+
+          expect(issues).to contain_exactly(issue2, issue3)
+        end
+      end
+
       context 'filtering by issue term' do
         let(:params) { { search: 'git' } }