Allow close of broken MR

app/controllers/projects/merge_requests_controller.rb

@@ -79,6 +79,21 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   end
 
   def update
+    # If we close MergeRequest we want to ignore validation
+    # so we can close broken one (Ex. fork project removed)
+    if params[:merge_request] == {"state_event"=>"close"}
+      @merge_request.allow_broken = true
+
+      if @merge_request.close
+        opts = { notice: 'Merge request was successfully closed.' }
+      else
+        opts = { alert: 'Failed to close merge request.' }
+      end
+
+      redirect_to [@merge_request.target_project, @merge_request], opts
+      return
+    end
+
     if @merge_request.update_attributes(params[:merge_request].merge(author_id_of_changes: current_user.id))
       @merge_request.reload_code
       @merge_request.mark_as_unchecked

app/models/merge_request.rb

@@ -35,6 +35,10 @@ class MergeRequest < ActiveRecord::Base
 
   attr_accessor :should_remove_source_branch
 
+  # When this attribute is true some MR validation is ignored
+  # It allows us to close or modify broken merge requests
+  attr_accessor :allow_broken
+
   state_machine :state, initial: :opened do
     event :close do
       transition [:reopened, :opened] => :closed
@@ -80,7 +84,7 @@ class MergeRequest < ActiveRecord::Base
   serialize :st_commits
   serialize :st_diffs
 
-  validates :source_project, presence: true
+  validates :source_project, presence: true, unless: :allow_broken
   validates :source_branch, presence: true
   validates :target_project, presence: true
   validates :target_branch, presence: true

app/views/projects/merge_requests/show/_mr_title.html.haml

@@ -24,7 +24,7 @@
             %li= link_to "Email Patches", project_merge_request_path(@project, @merge_request, format: :patch)
             %li= link_to "Plain Diff",    project_merge_request_path(@project, @merge_request, format: :diff)
 
-        = link_to 'Close', project_merge_request_path(@project, @merge_request, merge_request: {state_event: :close }), method: :put, class: "btn grouped btn-close", title: "Close merge request"
+        = link_to 'Close', project_merge_request_path(@project, @merge_request, merge_request: { state_event: :close }), method: :put, class: "btn grouped btn-close", title: "Close merge request"
 
         = link_to edit_project_merge_request_path(@project, @merge_request), class: "btn grouped", id:"edit_merge_request" do
           %i.icon-edit