Fix weight quick action to support 0 value

ee/changelogs/unreleased/10324-weight-fix.yml

+---
+title: Fix weight quick action to support 0 value
+merge_request: 14432
+author:
+type: fixed

ee/lib/ee/gitlab/quick_actions/issue_and_merge_request_actions.rb

@@ -34,7 +34,7 @@ module EE
               current_user.can?(:"admin_#{quick_action_target.to_ability_name}", quick_action_target)
           end
           parse_params do |weight|
-            weight.to_i if weight.to_i > 0
+            weight.to_i if weight.to_i >= 0
           end
           command :weight do |weight|
             @updates[:weight] = weight if weight

ee/spec/services/ee/issues/update_service_spec.rb

@@ -27,6 +27,37 @@ describe Issues::UpdateService do
         end
       end
 
+      context 'updating weight' do
+        before do
+          project.add_maintainer(user)
+          issue.update(weight: 3)
+        end
+
+        context 'when weight is integer' do
+          it 'updates to the exact value' do
+            expect { update_issue(weight: 2) }.to change { issue.weight }.to(2)
+          end
+        end
+
+        context 'when weight is integer' do
+          it 'rounds the value down' do
+            expect { update_issue(weight: 1.8) }.to change { issue.weight }.to(1)
+          end
+        end
+
+        context 'when weight is zero' do
+          it 'sets the value to zero' do
+            expect { update_issue(weight: 0) }.to change { issue.weight }.to(0)
+          end
+        end
+
+        context 'when weight is a string' do
+          it 'sets the value to 0' do
+            expect { update_issue(weight: 'abc') }.to change { issue.weight }.to(0)
+          end
+        end
+      end
+
       context 'updating other fields' do
         it 'does not call epic#update_start_and_due_dates' do
           expect(epic).not_to receive(:update_start_and_due_dates)

ee/spec/services/quick_actions/interpret_service_spec.rb

@@ -682,19 +682,37 @@ describe QuickActions::InterpretService do
     end
 
     context 'issuable weights licensed' do
+      let(:issuable) { issue }
+
       before do
         stub_licensed_features(issue_weights: true)
       end
 
-      it_behaves_like 'weight command' do
-        let(:weight) { 5 }
+      context 'weight' do
         let(:content) { "/weight #{weight}" }
-        let(:issuable) { issue }
+
+        it_behaves_like 'weight command' do
+          let(:weight) { 5 }
+        end
+
+        it_behaves_like 'weight command' do
+          let(:weight) { 0 }
+        end
+
+        context 'when weight is negative' do
+          it 'does not populate weight' do
+            content = "/weight -10"
+            _, updates = service.execute(content, issuable)
+
+            expect(updates).to be_empty
+          end
+        end
       end
 
-      it_behaves_like 'clear weight command' do
-        let(:content) { '/clear_weight' }
-        let(:issuable) { issue }
+      context 'clear_weight' do
+        it_behaves_like 'clear weight command' do
+          let(:content) { '/clear_weight' }
+        end
       end
     end