1 files changed, 63 insertions, 7 deletions

diff --git a/app/controllers/projects/blob_controller.rb b/app/controllers/projects/blob_controller.rb
index 0c1c286a0a4..ebc61264b39 100644
--- a/app/controllers/projects/blob_controller.rb
+++ b/app/controllers/projects/blob_controller.rb
@@ -3,10 +3,11 @@ class Projects::BlobController < Projects::ApplicationController
   include ExtractsPath
   include CreatesCommit
   include RendersBlob
+  include NotesHelper
   include ActionView::Helpers::SanitizeHelper
-
   prepend_before_action :authenticate_user!, only: [:edit]
 
+  before_action :set_request_format, only: [:edit, :show, :update]
   before_action :require_non_empty_project, except: [:new, :create]
   before_action :authorize_download_code!
 
@@ -92,6 +93,7 @@ class Projects::BlobController < Projects::ApplicationController
     @lines = Gitlab::Highlight.highlight(@blob.path, @blob.data, repository: @repository).lines
 
     @form = UnfoldForm.new(params)
+
     @lines = @lines[@form.since - 1..@form.to - 1].map(&:html_safe)
 
     if @form.bottom?
@@ -102,11 +104,50 @@ class Projects::BlobController < Projects::ApplicationController
       @match_line = "@@ -#{line}+#{line} @@"
     end
 
-    render layout: false
+    # We can keep only 'render_diff_lines' from this conditional when
+    # https://gitlab.com/gitlab-org/gitlab-ce/issues/44988 is done
+    if rendered_for_merge_request?
+      render_diff_lines
+    else
+      render layout: false
+    end
   end
 
   private
 
+  # Converts a String array to Gitlab::Diff::Line array
+  def render_diff_lines
+    @lines.map! do |line|
+      # These are marked as context lines but are loaded from blobs.
+      # We also have context lines loaded from diffs in other places.
+      diff_line = Gitlab::Diff::Line.new(line, 'context', nil, nil, nil)
+      diff_line.rich_text = line
+      diff_line
+    end
+
+    add_match_line
+
+    render json: @lines
+  end
+
+  def add_match_line
+    return unless @form.unfold?
+
+    if @form.bottom? && @form.to < @blob.lines.size
+      old_pos = @form.to - @form.offset
+      new_pos = @form.to
+    elsif @form.since != 1
+      old_pos = new_pos = @form.since
+    end
+
+    # Match line is not needed when it reaches the top limit or bottom limit of the file.
+    return unless new_pos
+
+    @match_line = Gitlab::Diff::Line.new(@match_line, 'match', nil, old_pos, new_pos)
+
+    @form.bottom? ? @lines.push(@match_line) : @lines.unshift(@match_line)
+  end
+
   def blob
     @blob ||= @repository.blob_at(@commit.id, @path)
 
@@ -188,6 +229,18 @@ class Projects::BlobController < Projects::ApplicationController
       .last_for_path(@repository, @ref, @path).sha
   end
 
+  # In Rails 4.2 if params[:format] is empty, Rails set it to :html
+  # But since Rails 5.0 the framework now looks for an extension.
+  # E.g. for `blob/master/CHANGELOG.md` in Rails 4 the format would be `:html`, but in Rails 5 on it'd be `:md`
+  # This before_action explicitly sets the `:html` format for all requests unless `:format` is set by a client e.g. by JS for XHR requests.
+  def set_request_format
+    request.format = :html if set_request_format?
+  end
+
+  def set_request_format?
+    params[:id].present? && params[:format].blank? && request.format != "json"
+  end
+
   def show_html
     environment_params = @repository.branch_exists?(@ref) ? { ref: @ref } : { commit: @commit }
     @environment = EnvironmentsFinder.new(@project, current_user, environment_params).execute.last
@@ -197,15 +250,14 @@ class Projects::BlobController < Projects::ApplicationController
   end
 
   def show_json
-    json = blob_json(@blob)
-    return render_404 unless json
-
+    set_last_commit_sha
     path_segments = @path.split('/')
     path_segments.pop
     tree_path = path_segments.join('/')
 
-    render json: json.merge(
+    json = {
       id: @blob.id,
+      last_commit_sha: @last_commit_sha,
       path: blob.path,
       name: blob.name,
       extension: blob.extension,
@@ -221,6 +273,10 @@ class Projects::BlobController < Projects::ApplicationController
       commits_path: project_commits_path(project, @id),
       tree_path: project_tree_path(project, File.join(@ref, tree_path)),
       permalink: project_blob_path(project, File.join(@commit.id, @path))
-    )
+    }
+
+    json.merge!(blob_json(@blob) || {}) unless params[:viewer] == 'none'
+
+    render json: json
   end
 end