Fix diffs with edit-forking needs

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/31276

Conflicts:
	app/views/projects/blob/_header.html.haml

app/assets/javascripts/merge_request_tabs.js

@@ -5,6 +5,7 @@
 import Cookies from 'js-cookie';
 import './breakpoints';
 import './flash';
+import BlobForkSuggestion from './blob/blob_fork_suggestion';
 
 /* eslint-disable max-len */
 // MergeRequestTabs
@@ -266,6 +267,16 @@ import './flash';
 
           new gl.Diff();
           this.scrollToElement('#diffs');
+
+          $('.diff-file').each((i, el) => {
+            new BlobForkSuggestion({
+              openButtons: $(el).find('.js-edit-blob-link-fork-toggler'),
+              forkButtons: $(el).find('.js-fork-suggestion-button'),
+              cancelButtons: $(el).find('.js-cancel-fork-suggestion-button'),
+              suggestionSections: $(el).find('.js-file-fork-suggestion-section'),
+              actionTextPieces: $(el).find('.js-file-fork-suggestion-section-action'),
+            });
+          });
         },
       });
     }

app/helpers/blob_helper.rb

@@ -29,7 +29,7 @@ module BlobHelper
       link_to 'Edit', edit_path(project, ref, path, options), class: "#{common_classes} btn-sm"
     elsif current_user && can?(current_user, :fork_project, project)
       continue_params = {
-        to: edit_path,
+        to: edit_path(project, ref, path, options),
         notice: edit_in_new_fork_notice,
         notice_now: edit_in_new_fork_notice_now
       }

app/views/projects/_fork_suggestion.html.haml

+- if current_user
+  .js-file-fork-suggestion-section.file-fork-suggestion.hidden
+    %span.file-fork-suggestion-note
+      You're not allowed to
+      %span.js-file-fork-suggestion-section-action
+        edit
+      files in this project directly. Please fork this project,
+      make your changes there, and submit a merge request.
+    = link_to 'Fork', nil, method: :post, class: 'js-fork-suggestion-button btn btn-grouped btn-inverted btn-new'
+    %button.js-cancel-fork-suggestion-button.btn.btn-grouped{ type: 'button' }
+      Cancel

app/views/projects/blob/_header.html.haml

@@ -41,17 +41,7 @@
         = replace_blob_link
         = delete_blob_link
 
-- if current_user
-  .js-file-fork-suggestion-section.file-fork-suggestion.hidden
-    %span.file-fork-suggestion-note
-      You're not allowed to
-      %span.js-file-fork-suggestion-section-action
-        edit
-      files in this project directly. Please fork this project,
-      make your changes there, and submit a merge request.
-    = link_to 'Fork', nil, method: :post, class: 'js-fork-suggestion-button btn btn-grouped btn-inverted btn-new'
-    %button.js-cancel-fork-suggestion-button.btn.btn-grouped{ type: 'button' }
-      Cancel
+= render 'projects/fork_suggestion'
 
 - if license_allows_file_locks?
   :javascript

app/views/projects/diffs/_file.html.haml

@@ -18,4 +18,6 @@
         = view_file_button(diff_commit.id, diff_file.new_path, project)
         = view_on_environment_button(diff_commit.id, diff_file.new_path, environment) if environment
 
+  = render 'projects/fork_suggestion'
+
   = render 'projects/diffs/content', diff_file: diff_file, diff_commit: diff_commit, blob: blob, project: project

spec/features/merge_requests/diffs_spec.rb

 require 'spec_helper'
 
 feature 'Diffs URL', js: true, feature: true do
-  before do
-    login_as :admin
-    @merge_request = create(:merge_request)
-    @project = @merge_request.source_project
-  end
+  include ApplicationHelper
+
+  let(:author_user) { create(:user) }
+  let(:user) { create(:user) }
+  let(:project) { create(:project, :public) }
+  let(:forked_project) { Projects::ForkService.new(project, author_user).execute }
+  let(:merge_request) { create(:merge_request_with_diffs, source_project: forked_project, target_project: project, author: author_user) }
 
   context 'when visit with */* as accept header' do
     before(:each) do
@@ -13,9 +15,9 @@ feature 'Diffs URL', js: true, feature: true do
     end
 
     it 'renders the notes' do
-      create :note_on_merge_request, project: @project, noteable: @merge_request, note: 'Rebasing with master'
+      create :note_on_merge_request, project: project, noteable: merge_request, note: 'Rebasing with master'
 
-      visit diffs_namespace_project_merge_request_path(@project.namespace, @project, @merge_request)
+      visit diffs_namespace_project_merge_request_path(project.namespace, project, merge_request)
 
       # Load notes and diff through AJAX
       expect(page).to have_css('.note-text', visible: false, text: 'Rebasing with master')
@@ -28,11 +30,38 @@ feature 'Diffs URL', js: true, feature: true do
       allow_any_instance_of(MergeRequestDiff).to receive(:overflow?).and_return(true)
       allow(Commit).to receive(:max_diff_options).and_return(max_files: 20, max_lines: 20)
 
-      visit diffs_namespace_project_merge_request_path(@project.namespace, @project, @merge_request)
+      visit diffs_namespace_project_merge_request_path(project.namespace, project, merge_request)
 
       page.within('.alert') do
         expect(page).to have_text("Too many changes to show. Plain diff Email patch To preserve
-          performance only 3 of 3+ files are displayed.")
+          performance only 3 of 3 files are displayed.")
+      end
+    end
+  end
+
+  describe 'when editing file' do
+    let(:changelog_id) { hexdigest("CHANGELOG") }
+
+    context 'as author' do
+      it 'shows direct edit link' do
+        login_as(author_user)
+        visit diffs_namespace_project_merge_request_path(project.namespace, project, merge_request)
+
+        # Throws `Capybara::Poltergeist::InvalidSelector` if we try to use `#hash` syntax
+        expect(page).to have_selector("[id=\"#{changelog_id}\"] a.js-edit-blob")
+      end
+    end
+
+    context 'as user who needs to fork' do
+      it 'shows fork/cancel confirmation' do
+        login_as(user)
+        visit diffs_namespace_project_merge_request_path(project.namespace, project, merge_request)
+
+        # Throws `Capybara::Poltergeist::InvalidSelector` if we try to use `#hash` syntax
+        find("[id=\"#{changelog_id}\"] .js-edit-blob").click
+
+        expect(page).to have_selector('.js-fork-suggestion-button', count: 1)
+        expect(page).to have_selector('.js-cancel-fork-suggestion-button', count: 1)
       end
     end
   end