Merge branch '20454-edit-button-mr' into 'master'

edit_blob_link can receive the blob to avoid access to the repository

## What does this MR do?

Avoid access to the repository to get the blob when can be passed on context

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

#20454 to try to speed up the diff pages

## What are the relevant issue numbers?

Relates #20454 probably we want and UI solution not just a backend solution

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- ~~[ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)~~
- ~~[ ] API support added~~
- Tests
  - [x] Added for this feature/bug
  - [ ] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)


See merge request !5850

4 files changed, 31 insertions, 12 deletions

diff --git a/CHANGELOG b/CHANGELOG
index d32aff4b83f..31203b3d691 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -106,6 +106,7 @@ v 8.11.0 (unreleased)
   - Add commit stats in commit api. !5517 (dixpac)
   - Add CI configuration button on project page
   - Fix merge request new view not changing code view rendering style
+  - edit_blob_link will use blob passed onto the options parameter
   - Make error pages responsive (Takuya Noguchi)
   - The performance of the project dropdown used for moving issues has been improved
   - Fix skip_repo parameter being ignored when destroying a namespace
diff --git a/app/helpers/blob_helper.rb b/app/helpers/blob_helper.rb
index 1cb5d847626..9ea03720c1e 100644
--- a/app/helpers/blob_helper.rb
+++ b/app/helpers/blob_helper.rb
@@ -11,17 +11,14 @@ module BlobHelper
   def edit_blob_link(project = @project, ref = @ref, path = @path, options = {})
     return unless current_user
 
-    blob = project.repository.blob_at(ref, path) rescue nil
+    blob = options.delete(:blob)
+    blob ||= project.repository.blob_at(ref, path) rescue nil
 
     return unless blob
 
-    from_mr = options[:from_merge_request_id]
-    link_opts = {}
-    link_opts[:from_merge_request_id] = from_mr if from_mr
-
     edit_path = namespace_project_edit_blob_path(project.namespace, project,
                                      tree_join(ref, path),
-                                     link_opts)
+                                     options[:link_opts])
 
     if !on_top_of_branch?(project, ref)
       button_tag "Edit", class: "btn disabled has-tooltip btn-file-option", title: "You can only edit files when you are on a branch", data: { container: 'body' }
diff --git a/app/views/projects/diffs/_file.html.haml b/app/views/projects/diffs/_file.html.haml
index 8fbd89100ca..ad2eb3e504f 100644
--- a/app/views/projects/diffs/_file.html.haml
+++ b/app/views/projects/diffs/_file.html.haml
@@ -10,10 +10,9 @@
           \
 
           - if editable_diff?(diff_file)
-            = edit_blob_link(@merge_request.source_project,
-                @merge_request.source_branch, diff_file.new_path,
-                from_merge_request_id: @merge_request.id,
-                skip_visible_check: true)
+            - link_opts = @merge_request.id ? { from_merge_request_id: @merge_request.id } : {}
+            = edit_blob_link(@merge_request.source_project, @merge_request.source_branch, diff_file.new_path,
+                             blob: blob, link_opts: link_opts)
 
         = view_file_btn(diff_commit.id, diff_file.new_path, project)
 
diff --git a/spec/helpers/blob_helper_spec.rb b/spec/helpers/blob_helper_spec.rb
index 94972eed945..a43a7238c70 100644
--- a/spec/helpers/blob_helper_spec.rb
+++ b/spec/helpers/blob_helper_spec.rb
@@ -69,18 +69,40 @@ describe BlobHelper do
   end
 
   describe "#edit_blob_link" do
-    let(:project) { create(:project) }
+    let(:namespace) { create(:namespace, name: 'gitlab' )}
+    let(:project) { create(:project, namespace: namespace) }
 
     before do
       allow(self).to receive(:current_user).and_return(double)
+      allow(self).to receive(:can_collaborate_with_project?).and_return(true)
     end
 
     it 'verifies blob is text' do
-      expect(self).not_to receive(:blob_text_viewable?)
+      expect(helper).not_to receive(:blob_text_viewable?)
 
       button = edit_blob_link(project, 'refs/heads/master', 'README.md')
 
       expect(button).to start_with('<button')
     end
+
+    it 'uses the passed blob instead retrieve from repository' do
+      blob = project.repository.blob_at('refs/heads/master', 'README.md')
+
+      expect(project.repository).not_to receive(:blob_at)
+
+      edit_blob_link(project, 'refs/heads/master', 'README.md', blob: blob)
+    end
+
+    it 'returns a link with the proper route' do
+      link = edit_blob_link(project, 'master', 'README.md')
+
+      expect(Capybara.string(link).find_link('Edit')[:href]).to eq('/gitlab/gitlabhq/edit/master/README.md')
+    end
+
+    it 'returns a link with the passed link_opts on the expected route' do
+      link = edit_blob_link(project, 'master', 'README.md', link_opts: { mr_id: 10 })
+
+      expect(Capybara.string(link).find_link('Edit')[:href]).to eq('/gitlab/gitlabhq/edit/master/README.md?mr_id=10')
+    end
   end
 end