Merge branch 'empty-mrs' into 'master'

Allows empty merge requests for a workflow described in gitlab-org/gitlab-ce#14606

Closes gitlab-org/gitlab-ce#14606

See merge request !6384

CHANGELOG

@@ -85,6 +85,7 @@ v 8.13.0 (unreleased)
   - Changed Slack service user referencing from full name to username (Sebastian Poxhofer)
   - Retouch environments list and deployments list
   - Add Container Registry on/off status to Admin Area !6638 (the-undefined)
+  - Allow empty merge requests !6384 (Artem Sidorenko)
   - Grouped pipeline dropdown is a scrollable container
   - Cleanup Ci::ApplicationController. !6757 (Takuya Noguchi)
   - Fix a typo in doc/api/labels.md

app/assets/stylesheets/pages/merge_requests.scss

@@ -204,6 +204,18 @@
   word-break: break-all;
 }
 
+.commits-empty {
+  text-align: center;
+
+  h4 {
+    padding-top: 20px;
+    padding-bottom: 10px;
+  }
+  svg {
+    width: 230px;
+  }
+}
+
 .mr-list {
   .merge-request {
     padding: 10px 15px;

app/services/merge_requests/build_service.rb

@@ -4,7 +4,7 @@ module MergeRequests
       merge_request = MergeRequest.new(params)
 
       # Set MR attributes
-      merge_request.can_be_created = false
+      merge_request.can_be_created = true
       merge_request.compare_commits = []
       merge_request.source_project = project unless merge_request.source_project
 
@@ -22,6 +22,12 @@ module MergeRequests
         return build_failed(merge_request, message)
       end
 
+      if merge_request.source_project == merge_request.target_project &&
+         merge_request.target_branch == merge_request.source_branch
+
+        return build_failed(merge_request, 'You must select different branches')
+      end
+
       compare = CompareService.new.execute(
         merge_request.source_project,
         merge_request.source_branch,
@@ -29,17 +35,8 @@ module MergeRequests
         merge_request.target_branch,
       )
 
-      commits = compare.commits
-
-      # At this point we decide if merge request can be created
-      # If we have at least one commit to merge -> creation allowed
-      if commits.present?
-        merge_request.compare_commits = commits
-        merge_request.can_be_created = true
+      merge_request.compare_commits = compare.commits
       merge_request.compare = compare
-      else
-        merge_request.can_be_created = false
-      end
 
       set_title_and_description(merge_request)
     end
@@ -89,6 +86,8 @@ module MergeRequests
         end
       end
 
+      merge_request.title = merge_request.wip_title if commits.empty?
+
       merge_request
     end
 

app/views/projects/merge_requests/_new_compare.html.haml

@@ -65,19 +65,6 @@
 
   - if @merge_request.errors.any?
     = form_errors(@merge_request)
-  - elsif @merge_request.source_branch.present? && @merge_request.target_branch.present?
-    .light-well.append-bottom-default
-      .center
-        %h4
-          There isn't anything to merge.
-        %p.slead
-          - if @merge_request.source_branch == @merge_request.target_branch
-            You'll need to use different branch names to get a valid comparison.
-          - else
-            %span.label-branch #{@merge_request.source_branch}
-            and
-            %span.label-branch #{@merge_request.target_branch}
-            are the same.
   = f.submit 'Compare branches and continue', class: "btn btn-new mr-compare-btn"
 
 :javascript

app/views/projects/merge_requests/_new_submit.html.haml

@@ -18,6 +18,12 @@
   = f.hidden_field :target_branch
 
 .mr-compare.merge-request
+  - if @commits.empty?
+    .commits-empty
+      %h4
+        There are no commits yet.
+      = custom_icon ('illustration_no_commits')
+  - else
     %ul.merge-request-tabs.nav-links.no-top.no-bottom
       %li.commits-tab.active
         = link_to url_for(params), data: {target: 'div#commits', action: 'new', toggle: 'tab'} do

app/views/shared/icons/_illustration_no_commits.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 168 107" xmlns:xlink="http://www.w3.org/1999/xlink"><g fill="#eee" fill-rule="evenodd"><path d="m4.01 2h1.102c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-1.102c-2.218 0-4.01 1.788-4.01 4 0 .552.448 1 1 1 .552 0 1-.448 1-1 0-1.108.892-2 2.01-2m12.702 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m11.6 0c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7m8.088 0c.822 0 1.554.503 1.86 1.254.208.512.791.758 1.303.55.512-.208.758-.791.55-1.303-.609-1.497-2.069-2.5-3.712-2.5h-2.188c-.552 0-1 .448-1 1 0 .552.448 1 1 1h2.188m2.01 12.518c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7m0 11.6c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7m0 11.6c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7m0 6.282c0 1.108-.892 2-2.01 2h-.72c-.552 0-1 .448-1 1 0 .552.448 1 1 1h.72c2.218 0 4.01-1.788 4.01-4v-.382c0-.552-.448-1-1-1-.552 0-1 .448-1 1v.382m-14.325 2c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-11.6 0c-.552 0-1 .448-1 1 0 .552.448 1 1 1h5.7c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-5.7m-8.47 0c-.755 0-1.438-.424-1.782-1.085-.255-.49-.859-.681-1.349-.426-.49.255-.681.859-.426 1.349.684 1.316 2.046 2.162 3.556 2.162h2.57c.552 0 1-.448 1-1 0-.552-.448-1-1-1h-2.57m-2.01-12.136c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7m0-11.6c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7m0-11.6c0-.552-.448-1-1-1-.552 0-1 .448-1 1v5.7c0 .552.448 1 1 1 .552 0 1-.448 1-1v-5.7m0-6.664c0-.552-.448-1-1-1-.552 0-1 .448-1 1v.764c0 .552.448 1 1 1 .552 0 1-.448 1-1v-.764" id="0"/><circle cx="21" cy="24" r="10"/><rect width="33" height="3" x="37" y="18" rx="1.5" id="1"/><rect width="53" height="3" x="37" y="27" rx="1.5" id="2"/><path d="m131 29c0 .552.447.999.996.999h22.01c.545 0 .996-.451.996-.999v-9c0-.552-.447-.999-.996-.999h-22.01c-.545 0-.996.451-.996.999v9m.996-12h22.01c1.655 0 2.996 1.344 2.996 2.999v9c0 1.657-1.35 2.999-2.996 2.999h-22.01c-1.655 0-2.996-1.344-2.996-2.999v-9c0-1.657 1.35-2.999 2.996-2.999" id="3"/><g transform="translate(0 59)"><use xlink:href="#0"/><circle cx="21" cy="24" r="10"/><use xlink:href="#1"/><use xlink:href="#2"/><use xlink:href="#3"/></g></g></svg>
\ No newline at end of file

spec/services/merge_requests/build_service_spec.rb

@@ -52,12 +52,28 @@ describe MergeRequests::BuildService, services: true do
       end
     end
 
-    context 'no commits in the diff' do
-      let(:commits) { [] }
+    context 'same source and target branch' do
+      let(:source_branch) { 'master' }
 
       it 'forbids the merge request from being created' do
         expect(merge_request.can_be_created).to eq(false)
       end
+
+      it 'adds an error message to the merge request' do
+        expect(merge_request.errors).to contain_exactly('You must select different branches')
+      end
+    end
+
+    context 'no commits in the diff' do
+      let(:commits) { [] }
+
+      it 'allows the merge request to be created' do
+        expect(merge_request.can_be_created).to eq(true)
+      end
+
+      it 'adds a WIP prefix to the merge request title' do
+        expect(merge_request.title).to eq('WIP: Feature branch')
+      end
     end
 
     context 'one commit in the diff' do