Merge branch '28124-mrs-don-t-show-all-merge-errors' into 'master'

Show merge errors in merge request widget

Closes #28124 and gitlab-ee#1652

See merge request !9229

app/assets/javascripts/merge_request_widget.js.es6

@@ -110,7 +110,7 @@ require('./smart_interval');
               urlSuffix = deleteSourceBranch ? '?deleted_source_branch=true' : '';
               return window.location.href = window.location.pathname + urlSuffix;
             } else if (data.merge_error) {
-              return _this.$widgetBody.html("<h4>" + data.merge_error + "</h4>");
+              return $('.mr-widget-body').html("<h4>" + data.merge_error + "</h4>");
             } else {
               callback = function() {
                 return merge_request_widget.mergeInProgress(deleteSourceBranch);

app/services/merge_requests/merge_service.rb

@@ -11,18 +11,20 @@ module MergeRequests
     def execute(merge_request)
       @merge_request = merge_request
 
-      return log_merge_error('Merge request is not mergeable', true) unless @merge_request.mergeable?
+      unless @merge_request.mergeable?
+        return log_merge_error('Merge request is not mergeable', save_message_on_model: true)
+      end
 
       @source = find_merge_source
 
-      return log_merge_error('No source for merge', true) unless @source
+      unless @source
+        log_merge_error('No source for merge', save_message_on_model: true)
+      end
 
       merge_request.in_locked_state do
         if commit
           after_merge
           success
-        else
-          log_merge_error('Can not merge changes', true)
         end
       end
     end
@@ -43,11 +45,11 @@ module MergeRequests
       if commit_id
         merge_request.update(merge_commit_sha: commit_id)
       else
-        merge_request.update(merge_error: 'Conflicts detected during merge')
+        log_merge_error('Conflicts detected during merge', save_message_on_model: true)
         false
       end
     rescue GitHooksService::PreReceiveError => e
-      merge_request.update(merge_error: e.message)
+      log_merge_error(e.message, save_message_on_model: true)
       false
     rescue StandardError => e
       merge_request.update(merge_error: "Something went wrong during merge: #{e.message}")
@@ -70,10 +72,10 @@ module MergeRequests
       @merge_request.force_remove_source_branch? ? @merge_request.author : current_user
     end
 
-    def log_merge_error(message, http_error = false)
+    def log_merge_error(message, save_message_on_model: false)
       Rails.logger.error("MergeService ERROR: #{merge_request_info} - #{message}")
 
-      error(message) if http_error
+      @merge_request.update(merge_error: message) if save_message_on_model
     end
 
     def merge_request_info

changelogs/unreleased/28124-mrs-don-t-show-all-merge-errors.yml

+---
+title: Show merge errors in merge request widget
+merge_request: 9229
+author:

spec/features/merge_requests/widget_spec.rb

@@ -52,4 +52,19 @@ describe 'Merge request', :feature, :js do
       end
     end
   end
+
+  context 'merge error' do
+    before do
+      allow_any_instance_of(Repository).to receive(:merge).and_return(false)
+      visit namespace_project_merge_request_path(project.namespace, project, merge_request)
+      click_button 'Accept Merge Request'
+      wait_for_ajax
+    end
+
+    it 'updates the MR widget' do
+      page.within('.mr-widget-body') do
+        expect(page).to have_content('Conflicts detected during merge')
+      end
+    end
+  end
 end

spec/services/merge_requests/merge_service_spec.rb

@@ -149,35 +149,46 @@ describe MergeRequests::MergeService, services: true do
     context "error handling" do
       let(:service) { MergeRequests::MergeService.new(project, user, commit_message: 'Awesome message') }
 
-      it 'saves error if there is an exception' do
-        allow(service).to receive(:repository).and_raise("error message")
+      before do
+        allow(Rails.logger).to receive(:error)
+      end
 
+      it 'logs and saves error if there is an exception' do
+        error_message = 'error message'
+
+        allow(service).to receive(:repository).and_raise("error message")
         allow(service).to receive(:execute_hooks)
 
         service.execute(merge_request)
 
-        expect(merge_request.merge_error).to eq("Something went wrong during merge: error message")
+        expect(merge_request.merge_error).to include(error_message)
+        expect(Rails.logger).to have_received(:error).with(a_string_matching(error_message))
       end
 
-      it 'saves error if there is an PreReceiveError exception' do
-        allow(service).to receive(:repository).and_raise(GitHooksService::PreReceiveError, "error")
+      it 'logs and saves error if there is an PreReceiveError exception' do
+        error_message = 'error message'
 
+        allow(service).to receive(:repository).and_raise(GitHooksService::PreReceiveError, error_message)
         allow(service).to receive(:execute_hooks)
 
         service.execute(merge_request)
 
-        expect(merge_request.merge_error).to eq("error")
+        expect(merge_request.merge_error).to include(error_message)
+        expect(Rails.logger).to have_received(:error).with(a_string_matching(error_message))
       end
 
-      it 'aborts if there is a merge conflict' do
+      it 'logs and saves error if there is a merge conflict' do
+        error_message = 'Conflicts detected during merge'
+
         allow_any_instance_of(Repository).to receive(:merge).and_return(false)
         allow(service).to receive(:execute_hooks)
 
         service.execute(merge_request)
 
-        expect(merge_request.open?).to be_truthy
+        expect(merge_request).to be_open
         expect(merge_request.merge_commit_sha).to be_nil
-        expect(merge_request.merge_error).to eq("Conflicts detected during merge")
+        expect(merge_request.merge_error).to include(error_message)
+        expect(Rails.logger).to have_received(:error).with(a_string_matching(error_message))
       end
     end
   end