Make rebase-required messages clearer for users

app/assets/javascripts/vue_merge_request_widget/components/states/mr_widget_conflicts.vue

@@ -112,7 +112,7 @@ export default {
     <div v-else class="media-body space-children gl-display-flex gl-align-items-center">
       <span v-if="shouldBeRebased" class="bold">
         {{
-          s__(`mrWidget|Fast-forward merge is not possible.
+          s__(`mrWidget|Merge blocked: fast-forward merge is not possible.
   To merge this request, first rebase locally.`)
         }}
       </span>

app/assets/javascripts/vue_merge_request_widget/components/states/mr_widget_rebase.vue

@@ -87,9 +87,7 @@ export default {
     },
     fastForwardMergeText() {
       return sprintf(
-        __(
-          'Fast-forward merge is not possible. Rebase the source branch onto %{targetBranch} to allow this merge request to be merged.',
-        ),
+        __('Merge blocked: the source branch must be rebased onto the target branch.'),
         {
           targetBranch: `<span class="label-branch">${escape(this.targetBranch)}</span>`,
         },
@@ -193,9 +191,7 @@ export default {
             data-testid="rebase-message"
             data-qa-selector="no_fast_forward_message_content"
             >{{
-              __(
-                'Fast-forward merge is not possible. Rebase the source branch onto the target branch.',
-              )
+              __('Merge blocked: the source branch must be rebased onto the target branch.')
             }}</span
           >
           <span v-else class="gl-font-weight-bold danger" data-testid="rebase-message">{{

locale/gitlab.pot

@@ -13602,12 +13602,6 @@ msgstr ""
 msgid "Fast timeout"
 msgstr ""
 
-msgid "Fast-forward merge is not possible. Rebase the source branch onto %{targetBranch} to allow this merge request to be merged."
-msgstr ""
-
-msgid "Fast-forward merge is not possible. Rebase the source branch onto the target branch."
-msgstr ""
-
 msgid "Fast-forward merge without a merge commit"
 msgstr ""
 
@@ -20426,6 +20420,9 @@ msgstr ""
 msgid "Merge automatically (%{strategy})"
 msgstr ""
 
+msgid "Merge blocked: the source branch must be rebased onto the target branch."
+msgstr ""
+
 msgid "Merge commit SHA"
 msgstr ""
 
@@ -38979,9 +38976,6 @@ msgstr ""
 msgid "mrWidget|Failed to load deployment statistics"
 msgstr ""
 
-msgid "mrWidget|Fast-forward merge is not possible. To merge this request, first rebase locally."
-msgstr ""
-
 msgid "mrWidget|If the %{missingBranchName} branch exists in your local repository, you can merge this merge request manually using the command line"
 msgstr ""
 
@@ -39009,6 +39003,9 @@ msgstr ""
 msgid "mrWidget|Merge blocked: all threads must be resolved."
 msgstr ""
 
+msgid "mrWidget|Merge blocked: fast-forward merge is not possible. To merge this request, first rebase locally."
+msgstr ""
+
 msgid "mrWidget|Merge blocked: pipeline must succeed. It's waiting for a manual action to continue."
 msgstr ""
 

spec/features/merge_request/user_sees_merge_widget_spec.rb

@@ -373,7 +373,7 @@ RSpec.describe 'Merge request > User sees merge widget', :js do
       wait_for_requests
 
       page.within('.mr-widget-body') do
-        expect(page).to have_content('Fast-forward merge is not possible')
+        expect(page).to have_content('Merge Merge blocked: fast-forward merge is not possible. To merge this request, first rebase locally.')
       end
     end
   end

spec/frontend/vue_mr_widget/components/mr_widget_rebase_spec.js

@@ -70,9 +70,9 @@ describe('Merge request widget rebase component', () => {
 
           const text = findRebaseMessageElText();
 
-          expect(text).toContain('Fast-forward merge is not possible.');
+          expect(text).toContain('Merge blocked');
           expect(text.replace(/\s\s+/g, ' ')).toContain(
-            'Rebase the source branch onto the target branch.',
+            'the source branch must be rebased onto the target branch',
           );
         });
 
@@ -111,12 +111,10 @@ describe('Merge request widget rebase component', () => {
 
           const text = findRebaseMessageElText();
 
-          expect(text).toContain('Fast-forward merge is not possible.');
-          expect(text).toContain('Rebase the source branch onto');
-          expect(text).toContain('foo');
-          expect(text.replace(/\s\s+/g, ' ')).toContain(
-            'to allow this merge request to be merged.',
+          expect(text).toContain(
+            'Merge blocked: the source branch must be rebased onto the target branch.',
           );
+          expect(text).toContain('the source branch must be rebased');
         });
 
         it('should render the correct target branch name', () => {
@@ -136,7 +134,7 @@ describe('Merge request widget rebase component', () => {
           const elem = findRebaseMessageEl();
 
           expect(elem.text()).toContain(
-            `Fast-forward merge is not possible. Rebase the source branch onto ${targetBranch} to allow this merge request to be merged.`,
+            `Merge blocked: the source branch must be rebased onto the target branch.`,
           );
         });
       });

spec/frontend/vue_mr_widget/components/states/mr_widget_conflicts_spec.js

@@ -199,7 +199,7 @@ describe('MRWidgetConflicts', () => {
           });
 
           expect(removeBreakLine(wrapper.text()).trim()).toContain(
-            'Fast-forward merge is not possible. To merge this request, first rebase locally.',
+            'Merge blocked: fast-forward merge is not possible. To merge this request, first rebase locally.',
           );
         });
       });