Improve readability and add specs for label filtering

app/finders/labels_finder.rb

@@ -35,13 +35,10 @@ class LabelsFinder < UnionFinder
   end
 
   def with_title(items)
-    if title
-      items.where(title: title)
-    elsif params[:title] || params[:name] # empty input, should match nothing
-      items.none
-    else # not filtering
-      items
-    end
+    return items if title.nil?
+    return items.none if title.blank?
+
+    items.where(title: title)
   end
 
   def group_id
@@ -57,7 +54,7 @@ class LabelsFinder < UnionFinder
   end
 
   def title
-    params[:title].presence || params[:name].presence
+    params[:title] || params[:name]
   end
 
   def project

spec/finders/labels_finder_spec.rb

@@ -38,6 +38,14 @@ describe LabelsFinder do
 
         expect(finder.execute).to eq [group_label_2, group_label_3, project_label_1, group_label_1, project_label_2, project_label_4]
       end
+
+      it 'returns labels available if nil title is supplied' do
+        group_2.add_developer(user)
+        # params[:title] will return `nil` regardless whether it is specified
+        finder = described_class.new(user, title: nil)
+
+        expect(finder.execute).to eq [group_label_2, group_label_3, project_label_1, group_label_1, project_label_2, project_label_4]
+      end
     end
 
     context 'filtering by group_id' do
@@ -71,13 +79,19 @@ describe LabelsFinder do
         expect(finder.execute).to eq [group_label_2]
       end
 
-      it 'returns no labels if empty titles are supplied' do
+      it 'returns no labels if empty title is supplied' do
         finder = described_class.new(user, title: [])
 
         expect(finder.execute).to be_empty
       end
 
-      it 'returns no labels if empty names are supplied' do
+      it 'returns no labels if blank title is supplied' do
+        finder = described_class.new(user, title: '')
+
+        expect(finder.execute).to be_empty
+      end
+
+      it 'returns no labels if empty name is supplied' do
         finder = described_class.new(user, name: [])
 
         expect(finder.execute).to be_empty