Merge branch 'master' into tmp-reference-pipeline-and-cachingtmp-reference-pipeline-and-caching

# Conflicts:
#	spec/lib/gitlab/markdown/autolink_filter_spec.rb
#	spec/lib/gitlab/markdown/commit_range_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/commit_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/cross_project_reference_spec.rb
#	spec/lib/gitlab/markdown/emoji_filter_spec.rb
#	spec/lib/gitlab/markdown/external_issue_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/external_link_filter_spec.rb
#	spec/lib/gitlab/markdown/issue_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/label_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/merge_request_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/redactor_filter_spec.rb
#	spec/lib/gitlab/markdown/reference_gatherer_filter_spec.rb
#	spec/lib/gitlab/markdown/relative_link_filter_spec.rb
#	spec/lib/gitlab/markdown/sanitization_filter_spec.rb
#	spec/lib/gitlab/markdown/snippet_reference_filter_spec.rb
#	spec/lib/gitlab/markdown/syntax_highlight_filter_spec.rb
#	spec/lib/gitlab/markdown/table_of_contents_filter_spec.rb
#	spec/lib/gitlab/markdown/task_list_filter_spec.rb
#	spec/lib/gitlab/markdown/upload_link_filter_spec.rb
#	spec/lib/gitlab/markdown/user_reference_filter_spec.rb

2 files changed, 37 insertions, 28 deletions

diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 96b73df6af9..81bf7a8222b 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -171,6 +171,7 @@ module API
       expose :description
       expose :work_in_progress?, as: :work_in_progress
       expose :milestone, using: Entities::Milestone
+      expose :merge_when_build_succeeds
     end
 
     class MergeRequestChanges < MergeRequest
diff --git a/lib/api/merge_requests.rb b/lib/api/merge_requests.rb
index e7c5f808aea..3c1c6bda260 100644
--- a/lib/api/merge_requests.rb
+++ b/lib/api/merge_requests.rb
@@ -195,46 +195,54 @@ module API
       # Merge MR
       #
       # Parameters:
-      #   id (required)                   - The ID of a project
-      #   merge_request_id (required)     - ID of MR
-      #   merge_commit_message (optional) - Custom merge commit message
+      #   id (required)                           - The ID of a project
+      #   merge_request_id (required)             - ID of MR
+      #   merge_commit_message (optional)         - Custom merge commit message
+      #   should_remove_source_branch (optional)  - When true, the source branch will be deleted if possible
+      #   merge_when_build_succeeds (optional)    - When true, this MR will be merged when the build succeeds
       # Example:
       #   PUT /projects/:id/merge_request/:merge_request_id/merge
       #
       put ":id/merge_request/:merge_request_id/merge" do
         merge_request = user_project.merge_requests.find(params[:merge_request_id])
 
-        allowed = ::Gitlab::GitAccess.new(current_user, user_project).
-          can_push_to_branch?(merge_request.target_branch)
+        # Merge request can not be merged
+        # because user dont have permissions to push into target branch
+        unauthorized! unless merge_request.can_be_merged_by?(current_user)
+        not_allowed! if !merge_request.open? || merge_request.work_in_progress?
 
-        if allowed
-          if merge_request.unchecked?
-            merge_request.check_if_can_be_merged
-          end
+        merge_request.check_if_can_be_merged if merge_request.unchecked?
 
-          if merge_request.open? && !merge_request.work_in_progress?
-            if merge_request.can_be_merged?
-              commit_message = params[:merge_commit_message] || merge_request.merge_commit_message
-
-              ::MergeRequests::MergeService.new(merge_request.target_project, current_user).
-                execute(merge_request, commit_message)
-
-              present merge_request, with: Entities::MergeRequest
-            else
-              render_api_error!('Branch cannot be merged', 405)
-            end
-          else
-            # Merge request can not be merged
-            # because it is already closed/merged or marked as WIP
-            not_allowed!
-          end
+        render_api_error!('Branch cannot be merged', 406) unless merge_request.can_be_merged?
+
+        merge_params = {
+          commit_message: params[:merge_commit_message],
+          should_remove_source_branch: params[:should_remove_source_branch]
+        }
+
+        if parse_boolean(params[:merge_when_build_succeeds]) && merge_request.ci_commit && merge_request.ci_commit.active?
+          ::MergeRequests::MergeWhenBuildSucceedsService.new(merge_request.target_project, current_user, merge_params).
+            execute(merge_request)
         else
-          # Merge request can not be merged
-          # because user dont have permissions to push into target branch
-          unauthorized!
+          ::MergeRequests::MergeService.new(merge_request.target_project, current_user, merge_params).
+            execute(merge_request)
         end
+
+        present merge_request, with: Entities::MergeRequest
       end
 
+      # Cancel Merge if Merge When build succeeds is enabled
+      # Parameters:
+      #   id (required)                         - The ID of a project
+      #   merge_request_id (required)           - ID of MR
+      #
+      post ":id/merge_request/:merge_request_id/cancel_merge_when_build_succeeds" do
+        merge_request = user_project.merge_requests.find(params[:merge_request_id])
+
+        unauthorized! unless merge_request.can_cancel_merge_when_build_succeeds?(current_user)
+
+        ::MergeRequest::MergeWhenBuildSucceedsService.new(merge_request.target_project, current_user).cancel(merge_request)
+      end
 
       # Get a merge request's comments
       #