Merge branch 'hide-empty-merge-request-diffs' into 'master'

Fix errors happening when source branch of merge request is removed and then restored

See merge request !7568

4 files changed, 19 insertions, 20 deletions

diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index b343ba0b744..dbbd2ad849e 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -82,12 +82,12 @@ class Projects::MergeRequestsController < Projects::ApplicationController
 
     @merge_request_diff =
       if params[:diff_id]
-        @merge_request.merge_request_diffs.find(params[:diff_id])
+        @merge_request.merge_request_diffs.viewable.find(params[:diff_id])
       else
         @merge_request.merge_request_diff
       end
 
-    @merge_request_diffs = @merge_request.merge_request_diffs.select_without_diff
+    @merge_request_diffs = @merge_request.merge_request_diffs.viewable.select_without_diff
     @comparable_diffs = @merge_request_diffs.select { |diff| diff.id < @merge_request_diff.id }
 
     if params[:start_sha].present?
@@ -417,7 +417,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
 
     response = {
       title: merge_request.title,
-      sha: merge_request.diff_head_commit.short_id,
+      sha: (merge_request.diff_head_commit.short_id if merge_request.diff_head_sha),
       status: status,
       coverage: coverage
     }
@@ -564,7 +564,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   def define_pipelines_vars
     @pipelines = @merge_request.all_pipelines
 
-    if @pipelines.present?
+    if @pipelines.present? && @merge_request.commits.present?
       @pipeline = @pipelines.first
       @statuses = @pipeline.statuses.relevant
     end
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index dd65a9a8b86..58a24eb84cb 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -11,6 +11,9 @@ class MergeRequestDiff < ActiveRecord::Base
 
   belongs_to :merge_request
 
+  serialize :st_commits
+  serialize :st_diffs
+
   state_machine :state, initial: :empty do
     state :collected
     state :overflow
@@ -22,8 +25,7 @@ class MergeRequestDiff < ActiveRecord::Base
     state :overflow_diff_lines_limit
   end
 
-  serialize :st_commits
-  serialize :st_diffs
+  scope :viewable, -> { without_state(:empty) }
 
   # All diff information is collected from repository after object is created.
   # It allows you to override variables like head_commit_sha before getting diff.
diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index 4a7e6930842..22596b4014a 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -60,7 +60,15 @@ module MergeRequests
       merge_requests = filter_merge_requests(merge_requests)
 
       merge_requests.each do |merge_request|
-        reload_diff(merge_request) unless branch_removed?
+        if merge_request.source_branch == @branch_name || force_push?
+          merge_request.reload_diff
+        else
+          mr_commit_ids = merge_request.commits.map(&:id)
+          push_commit_ids = @commits.map(&:id)
+          matches = mr_commit_ids & push_commit_ids
+          merge_request.reload_diff if matches.any?
+        end
+
         merge_request.mark_as_unchecked
       end
     end
@@ -165,16 +173,5 @@ module MergeRequests
     def branch_removed?
       Gitlab::Git.blank_ref?(@newrev)
     end
-
-    def reload_diff(merge_request)
-      if merge_request.source_branch == @branch_name || force_push?
-        merge_request.reload_diff
-      else
-        mr_commit_ids = merge_request.commits.map(&:id)
-        push_commit_ids = @commits.map(&:id)
-        matches = mr_commit_ids & push_commit_ids
-        merge_request.reload_diff if matches.any?
-      end
-    end
   end
 end
diff --git a/app/views/projects/merge_requests/widget/_open.html.haml b/app/views/projects/merge_requests/widget/_open.html.haml
index ac26aa569ba..20c93930abc 100644
--- a/app/views/projects/merge_requests/widget/_open.html.haml
+++ b/app/views/projects/merge_requests/widget/_open.html.haml
@@ -9,10 +9,10 @@
 
     - if @project.archived?
       = render 'projects/merge_requests/widget/open/archived'
-    - elsif @merge_request.commits.blank?
-      = render 'projects/merge_requests/widget/open/nothing'
     - elsif @merge_request.branch_missing?
       = render 'projects/merge_requests/widget/open/missing_branch'
+    - elsif @merge_request.commits.blank?
+      = render 'projects/merge_requests/widget/open/nothing'
     - elsif @merge_request.unchecked?
       = render 'projects/merge_requests/widget/open/check'
     - elsif @merge_request.cannot_be_merged? && !resolved_conflicts