From 2611d9f63cb6c22a00eccdac75535f93890b176c Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 01:41:46 -0700
Subject: [PATCH 1/8] Add a system note and update relevant merge requests when
 a branch is deleted or re-added

If a branch is deleted with an open merge request, amended offline, and then pushed again,
GitLab doesn't bother to update the merge request even though the last commit ID and/or
code may have changed. This MR ensures that each push will update any relevant merge
requests and adds a system note if this happens as well.

Closes #2926
---
 CHANGELOG                                     |  1 +
 app/models/merge_request_diff.rb              |  3 +-
 app/services/git_push_service.rb              |  5 +-
 .../merge_requests/refresh_service.rb         | 55 +++++++++++--------
 app/services/system_note_service.rb           | 19 +++++++
 spec/services/git_push_service_spec.rb        |  8 +++
 .../merge_requests/refresh_service_spec.rb    | 19 +++++++
 spec/services/system_note_service_spec.rb     | 12 ++++
 8 files changed, 98 insertions(+), 24 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 3992669214..814a6772cf 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -3,6 +3,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 v 8.1.0 (unreleased)
   - Fix error preventing displaying of commit data for a directory with a leading dot (Stan Hu)
   - Speed up load times of issue detail pages by roughly 1.5x
+  - Add a system note and update relevant merge requests when a branch is deleted or re-added (Stan Hu)
   - Make diff file view easier to use on mobile screens (Stan Hu)
   - Improved performance of finding users by username or Email address
   - Fix bug where merge request comments created by API would not trigger notifications (Stan Hu)
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index c9ef8023ae..bc2d691ece 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -163,7 +163,8 @@ class MergeRequestDiff < ActiveRecord::Base
         merge_request.fetch_ref
 
         # Get latest sha of branch from source project
-        source_sha = merge_request.source_project.commit(source_branch).sha
+        source_commit = merge_request.source_project.commit(source_branch)
+        source_sha = source_commit.try(:sha)
 
         Gitlab::CompareResult.new(
           Gitlab::Git::Compare.new(
diff --git a/app/services/git_push_service.rb b/app/services/git_push_service.rb
index 81d47602f1..e54044365b 100644
--- a/app/services/git_push_service.rb
+++ b/app/services/git_push_service.rb
@@ -49,10 +49,13 @@ class GitPushService
     elsif push_to_existing_branch?(ref, oldrev)
       # Collect data for this git push
       @push_commits = project.repository.commits_between(oldrev, newrev)
-      project.update_merge_requests(oldrev, newrev, ref, @user)
       process_commit_messages(ref)
     end
 
+    # Update merge requests that may be affected by this push. A new branch
+    # could cause the last commit of a merge request to change.
+    project.update_merge_requests(oldrev, newrev, ref, @user)
+
     @push_data = build_push_data(oldrev, newrev, ref)
 
     # If CI was disabled but .gitlab-ci.yml file was pushed
diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index e903e48e3c..802d02b079 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -6,12 +6,22 @@ module MergeRequests
       @oldrev, @newrev = oldrev, newrev
       @branch_name = Gitlab::Git.ref_name(ref)
       @fork_merge_requests = @project.fork_merge_requests.opened
-      @commits = @project.repository.commits_between(oldrev, newrev)
+      @commits = []
+      @merge_requests = merge_requests_for_branch
+
+      # Leave a system note if a branch were deleted/added
+      if Gitlab::Git.blank_ref?(oldrev) or Gitlab::Git.blank_ref?(newrev)
+        presence = Gitlab::Git.blank_ref?(oldrev) ? 'added' : 'deleted'
+        comment_mr_branch_presence_changed(presence)
+      else
+        @commits = @project.repository.commits_between(oldrev, newrev)
+
+        close_merge_requests
+        comment_mr_with_commits
+      end
 
-      close_merge_requests
       reload_merge_requests
       execute_mr_web_hooks
-      comment_mr_with_commits
 
       true
     end
@@ -31,7 +41,6 @@ module MergeRequests
         commit_ids.include?(merge_request.last_commit.id)
       end
 
-
       merge_requests.uniq.select(&:source_project).each do |merge_request|
         MergeRequests::PostMergeService.
           new(merge_request.target_project, @current_user).
@@ -46,11 +55,7 @@ module MergeRequests
     # Refresh merge request diff if we push to source or target branch of merge request
     # Note: we should update merge requests from forks too
     def reload_merge_requests
-      merge_requests = @project.merge_requests.opened.by_branch(@branch_name).to_a
-      merge_requests += @fork_merge_requests.by_branch(@branch_name).to_a
-      merge_requests = filter_merge_requests(merge_requests)
-
-      merge_requests.each do |merge_request|
+      @merge_requests.each do |merge_request|
 
         if merge_request.source_branch == @branch_name || force_push?
           merge_request.reload_code
@@ -70,13 +75,20 @@ module MergeRequests
       end
     end
 
-    # Add comment about pushing new commits to merge requests
-    def comment_mr_with_commits
-      merge_requests = @project.origin_merge_requests.opened.where(source_branch: @branch_name).to_a
-      merge_requests += @fork_merge_requests.where(source_branch: @branch_name).to_a
-      merge_requests = filter_merge_requests(merge_requests)
+    # Add comment about branches being deleted or added to merge requests
+    def comment_mr_branch_presence_changed(presence)
+      merge_requests = merge_requests_for_branch
 
       merge_requests.each do |merge_request|
+        SystemNoteService.change_branch_presence(
+            merge_request, merge_request.project, @current_user,
+            'source', @branch_name, presence)
+      end
+    end
+
+    # Add comment about pushing new commits to merge requests
+    def comment_mr_with_commits
+      @merge_requests.each do |merge_request|
         mr_commit_ids = Set.new(merge_request.commits.map(&:id))
 
         new_commits, existing_commits = @commits.partition do |commit|
@@ -91,14 +103,7 @@ module MergeRequests
 
     # Call merge request webhook with update branches
     def execute_mr_web_hooks
-      merge_requests = @project.origin_merge_requests.opened
-        .where(source_branch: @branch_name)
-        .to_a
-      merge_requests += @fork_merge_requests.where(source_branch: @branch_name)
-        .to_a
-      merge_requests = filter_merge_requests(merge_requests)
-
-      merge_requests.each do |merge_request|
+      @merge_requests.each do |merge_request|
         execute_hooks(merge_request, 'update')
       end
     end
@@ -106,5 +111,11 @@ module MergeRequests
     def filter_merge_requests(merge_requests)
       merge_requests.uniq.select(&:source_project)
     end
+
+    def merge_requests_for_branch
+      merge_requests = @project.origin_merge_requests.opened.where(source_branch: @branch_name).to_a
+      merge_requests += @fork_merge_requests.where(source_branch: @branch_name).to_a
+      filter_merge_requests(merge_requests)
+    end
   end
 end
diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index 8253c1f780..24e0650407 100644
--- a/app/services/system_note_service.rb
+++ b/app/services/system_note_service.rb
@@ -168,6 +168,25 @@ class SystemNoteService
     create_note(noteable: noteable, project: project, author: author, note: body)
   end
 
+  # Called when a branch in Noteable is added or deleted
+  #
+  # noteable    - Noteable object
+  # project     - Project owning noteable
+  # author      - User performing the change
+  # branch_type - 'source' or 'target'
+  # branch      - branch name
+  # presence    - 'deleted' or 'created'
+  #
+  # Example Note text:
+  #
+  #   "Target branch `feature` deleted"
+  #
+  # Returns the created Note object
+  def self.change_branch_presence(noteable, project, author, branch_type, branch, presence)
+    body = "#{branch_type} branch `#{branch}` #{presence}".capitalize
+    create_note(noteable: noteable, project: project, author: author, note: body)
+  end
+
   # Called when a Mentionable references a Noteable
   #
   # noteable  - Noteable object being referenced
diff --git a/spec/services/git_push_service_spec.rb b/spec/services/git_push_service_spec.rb
index fd72905c33..17015d29e5 100644
--- a/spec/services/git_push_service_spec.rb
+++ b/spec/services/git_push_service_spec.rb
@@ -112,6 +112,14 @@ describe GitPushService do
     it { expect(@event.project).to eq(project) }
     it { expect(@event.action).to eq(Event::PUSHED) }
     it { expect(@event.data).to eq(service.push_data) }
+
+    context "Updates merge requests" do
+      it "when pushing a new branch for the first time" do
+        expect(project).to receive(:update_merge_requests).
+                               with(@blankrev, 'newrev', 'refs/heads/master', user)
+        service.execute(project, user, @blankrev, 'newrev', 'refs/heads/master')
+      end
+    end
   end
 
   describe "Web Hooks" do
diff --git a/spec/services/merge_requests/refresh_service_spec.rb b/spec/services/merge_requests/refresh_service_spec.rb
index 9516e7936d..edb9fd0b43 100644
--- a/spec/services/merge_requests/refresh_service_spec.rb
+++ b/spec/services/merge_requests/refresh_service_spec.rb
@@ -106,6 +106,25 @@ describe MergeRequests::RefreshService do
       it { expect(@fork_merge_request.notes).to be_empty }
     end
 
+    context 'push new branch that exists in a merge request' do
+      let(:refresh_service) { service.new(@fork_project, @user) }
+      before do
+        allow(refresh_service).to receive(:execute_hooks)
+        refresh_service.execute(Gitlab::Git::BLANK_SHA, @newrev, 'refs/heads/master')
+        reload_mrs
+      end
+
+      it 'should execute hooks with update action' do
+        expect(refresh_service).to have_received(:execute_hooks).
+                                       with(@fork_merge_request, 'update')
+      end
+
+      it { expect(@merge_request.notes).to be_empty }
+      it { expect(@merge_request).to be_open }
+      it { expect(@fork_merge_request.notes.last.note).to include('Source branch `master` added') }
+      it { expect(@fork_merge_request).to be_open }
+    end
+
     def reload_mrs
       @merge_request.reload
       @fork_merge_request.reload
diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index 2658576640..108bc5995d 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -242,6 +242,18 @@ describe SystemNoteService do
     end
   end
 
+  describe '.change_branch_presence' do
+    subject { described_class.change_branch_presence(noteable, project, author, 'source', 'feature', 'deleted') }
+
+    it_behaves_like 'a system note'
+
+    context 'when source branch deleted' do
+      it 'sets the note text' do
+        expect(subject.note).to eq "Source branch `feature` deleted"
+      end
+    end
+  end
+
   describe '.cross_reference' do
     subject { described_class.cross_reference(noteable, mentioner, author) }
 

From 22775c596f9f8be79ec7599b561aa0ccb40bdc42 Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 01:57:45 -0700
Subject: [PATCH 2/8] Preserve target branch

---
 app/services/merge_requests/refresh_service.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index 802d02b079..8139aef2bb 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -55,7 +55,11 @@ module MergeRequests
     # Refresh merge request diff if we push to source or target branch of merge request
     # Note: we should update merge requests from forks too
     def reload_merge_requests
-      @merge_requests.each do |merge_request|
+      merge_requests = @project.merge_requests.opened.by_branch(@branch_name).to_a
+      merge_requests += @fork_merge_requests.by_branch(@branch_name).to_a
+      merge_requests = filter_merge_requests(merge_requests)
+
+      merge_requests.each do |merge_request|
 
         if merge_request.source_branch == @branch_name || force_push?
           merge_request.reload_code

From effa94bb878f4e9c208640c0f067b20cc004db2c Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 02:08:22 -0700
Subject: [PATCH 3/8] Improve SystemNote interface for branch add/restore case

---
 app/services/merge_requests/refresh_service.rb   | 16 +++++++---------
 app/services/system_note_service.rb              | 12 +++++++++---
 .../merge_requests/refresh_service_spec.rb       |  2 +-
 spec/services/system_note_service_spec.rb        |  4 ++--
 4 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index 8139aef2bb..fd15889343 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -7,11 +7,11 @@ module MergeRequests
       @branch_name = Gitlab::Git.ref_name(ref)
       @fork_merge_requests = @project.fork_merge_requests.opened
       @commits = []
-      @merge_requests = merge_requests_for_branch
+      @source_merge_requests = merge_requests_for_source_branch
 
       # Leave a system note if a branch were deleted/added
       if Gitlab::Git.blank_ref?(oldrev) or Gitlab::Git.blank_ref?(newrev)
-        presence = Gitlab::Git.blank_ref?(oldrev) ? 'added' : 'deleted'
+        presence = Gitlab::Git.blank_ref?(oldrev) ? :add : :delete
         comment_mr_branch_presence_changed(presence)
       else
         @commits = @project.repository.commits_between(oldrev, newrev)
@@ -81,18 +81,16 @@ module MergeRequests
 
     # Add comment about branches being deleted or added to merge requests
     def comment_mr_branch_presence_changed(presence)
-      merge_requests = merge_requests_for_branch
-
-      merge_requests.each do |merge_request|
+      @source_merge_requests.each do |merge_request|
         SystemNoteService.change_branch_presence(
             merge_request, merge_request.project, @current_user,
-            'source', @branch_name, presence)
+            :source, @branch_name, presence)
       end
     end
 
     # Add comment about pushing new commits to merge requests
     def comment_mr_with_commits
-      @merge_requests.each do |merge_request|
+      @source_merge_requests.each do |merge_request|
         mr_commit_ids = Set.new(merge_request.commits.map(&:id))
 
         new_commits, existing_commits = @commits.partition do |commit|
@@ -107,7 +105,7 @@ module MergeRequests
 
     # Call merge request webhook with update branches
     def execute_mr_web_hooks
-      @merge_requests.each do |merge_request|
+      @source_merge_requests.each do |merge_request|
         execute_hooks(merge_request, 'update')
       end
     end
@@ -116,7 +114,7 @@ module MergeRequests
       merge_requests.uniq.select(&:source_project)
     end
 
-    def merge_requests_for_branch
+    def merge_requests_for_source_branch
       merge_requests = @project.origin_merge_requests.opened.where(source_branch: @branch_name).to_a
       merge_requests += @fork_merge_requests.where(source_branch: @branch_name).to_a
       filter_merge_requests(merge_requests)
diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index 24e0650407..c0a5c3aeb5 100644
--- a/app/services/system_note_service.rb
+++ b/app/services/system_note_service.rb
@@ -173,9 +173,9 @@ class SystemNoteService
   # noteable    - Noteable object
   # project     - Project owning noteable
   # author      - User performing the change
-  # branch_type - 'source' or 'target'
+  # branch_type - :source or :target
   # branch      - branch name
-  # presence    - 'deleted' or 'created'
+  # presence    - :add or :delete
   #
   # Example Note text:
   #
@@ -183,7 +183,13 @@ class SystemNoteService
   #
   # Returns the created Note object
   def self.change_branch_presence(noteable, project, author, branch_type, branch, presence)
-    body = "#{branch_type} branch `#{branch}` #{presence}".capitalize
+    verb =
+      if presence == :add
+        'restored'
+      else
+        'deleted'
+      end
+    body = "#{branch_type.to_s} branch `#{branch}` #{verb}".capitalize
     create_note(noteable: noteable, project: project, author: author, note: body)
   end
 
diff --git a/spec/services/merge_requests/refresh_service_spec.rb b/spec/services/merge_requests/refresh_service_spec.rb
index edb9fd0b43..41eb5d41b2 100644
--- a/spec/services/merge_requests/refresh_service_spec.rb
+++ b/spec/services/merge_requests/refresh_service_spec.rb
@@ -121,7 +121,7 @@ describe MergeRequests::RefreshService do
 
       it { expect(@merge_request.notes).to be_empty }
       it { expect(@merge_request).to be_open }
-      it { expect(@fork_merge_request.notes.last.note).to include('Source branch `master` added') }
+      it { expect(@fork_merge_request.notes.last.note).to include('Source branch `master` restored') }
       it { expect(@fork_merge_request).to be_open }
     end
 
diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index 108bc5995d..16b1c66ff9 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -229,7 +229,7 @@ describe SystemNoteService do
   end
 
   describe '.change_branch' do
-    subject { described_class.change_branch(noteable, project, author, 'target', old_branch, new_branch) }
+    subject { described_class.change_branch(noteable, project, author, :target, old_branch, new_branch) }
     let(:old_branch) { 'old_branch'}
     let(:new_branch) { 'new_branch'}
 
@@ -243,7 +243,7 @@ describe SystemNoteService do
   end
 
   describe '.change_branch_presence' do
-    subject { described_class.change_branch_presence(noteable, project, author, 'source', 'feature', 'deleted') }
+    subject { described_class.change_branch_presence(noteable, project, author, 'source', 'feature', :delete) }
 
     it_behaves_like 'a system note'
 

From 9c67f4fb51719116737f9812d312f20eefebeacd Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 02:24:30 -0700
Subject: [PATCH 4/8] Memoize merge request source branches

---
 app/services/merge_requests/refresh_service.rb | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index fd15889343..0362b2d0ea 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -7,10 +7,9 @@ module MergeRequests
       @branch_name = Gitlab::Git.ref_name(ref)
       @fork_merge_requests = @project.fork_merge_requests.opened
       @commits = []
-      @source_merge_requests = merge_requests_for_source_branch
 
       # Leave a system note if a branch were deleted/added
-      if Gitlab::Git.blank_ref?(oldrev) or Gitlab::Git.blank_ref?(newrev)
+      if Gitlab::Git.blank_ref?(oldrev) || Gitlab::Git.blank_ref?(newrev)
         presence = Gitlab::Git.blank_ref?(oldrev) ? :add : :delete
         comment_mr_branch_presence_changed(presence)
       else
@@ -81,7 +80,7 @@ module MergeRequests
 
     # Add comment about branches being deleted or added to merge requests
     def comment_mr_branch_presence_changed(presence)
-      @source_merge_requests.each do |merge_request|
+      merge_requests_for_source_branch.each do |merge_request|
         SystemNoteService.change_branch_presence(
             merge_request, merge_request.project, @current_user,
             :source, @branch_name, presence)
@@ -90,7 +89,7 @@ module MergeRequests
 
     # Add comment about pushing new commits to merge requests
     def comment_mr_with_commits
-      @source_merge_requests.each do |merge_request|
+      merge_requests_for_source_branch.each do |merge_request|
         mr_commit_ids = Set.new(merge_request.commits.map(&:id))
 
         new_commits, existing_commits = @commits.partition do |commit|
@@ -105,7 +104,7 @@ module MergeRequests
 
     # Call merge request webhook with update branches
     def execute_mr_web_hooks
-      @source_merge_requests.each do |merge_request|
+      merge_requests_for_source_branch.each do |merge_request|
         execute_hooks(merge_request, 'update')
       end
     end
@@ -115,9 +114,11 @@ module MergeRequests
     end
 
     def merge_requests_for_source_branch
-      merge_requests = @project.origin_merge_requests.opened.where(source_branch: @branch_name).to_a
-      merge_requests += @fork_merge_requests.where(source_branch: @branch_name).to_a
-      filter_merge_requests(merge_requests)
+      @source_merge_requests ||= begin
+        merge_requests = @project.origin_merge_requests.opened.where(source_branch: @branch_name).to_a
+        merge_requests += @fork_merge_requests.where(source_branch: @branch_name).to_a
+        filter_merge_requests(merge_requests)
+      end
     end
   end
 end

From 577565d939d60cd48ce9e8aebc44663076af5aa2 Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 22:45:06 -0700
Subject: [PATCH 5/8] Add system notes for restored branches

---
 app/models/repository.rb                      |  4 +++
 .../merge_requests/refresh_service.rb         | 30 +++++++++++++++----
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/app/models/repository.rb b/app/models/repository.rb
index 8b51602bc2..921e1a9e42 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -480,6 +480,10 @@ class Repository
     end
   end
 
+  def merge_base(first_commit_id, second_commit_id)
+    rugged.merge_base(first_commit_id, second_commit_id)
+  end
+
   def search_files(query, ref)
     offset = 2
     args = %W(git grep -i -n --before-context #{offset} --after-context #{offset} #{query} #{ref || root_ref})
diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index 0362b2d0ea..7c4cb35ec6 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -10,13 +10,12 @@ module MergeRequests
 
       # Leave a system note if a branch were deleted/added
       if Gitlab::Git.blank_ref?(oldrev) || Gitlab::Git.blank_ref?(newrev)
-        presence = Gitlab::Git.blank_ref?(oldrev) ? :add : :delete
-        comment_mr_branch_presence_changed(presence)
+        comment_mr_branch_presence_changed
+        comment_mr_with_commits if @commits.present?
       else
         @commits = @project.repository.commits_between(oldrev, newrev)
-
-        close_merge_requests
         comment_mr_with_commits
+        close_merge_requests
       end
 
       reload_merge_requests
@@ -79,8 +78,29 @@ module MergeRequests
     end
 
     # Add comment about branches being deleted or added to merge requests
-    def comment_mr_branch_presence_changed(presence)
+    def comment_mr_branch_presence_changed
+      presence = Gitlab::Git.blank_ref?(@oldrev) ? :add : :delete
+
       merge_requests_for_source_branch.each do |merge_request|
+        last_commit = merge_request.last_commit
+
+        # Only look at changed commits in restore branch case
+        unless Gitlab::Git.blank_ref?(@newrev)
+          begin
+            # Since any number of commits could have been made to the restored branch,
+            # find the common root to see what has been added.
+            common_ref = @project.repository.merge_base(last_commit.id, @newrev)
+            # If the last_commit no longer exists in this new branch,
+            # gitlab_git throws a Rugged::OdbError
+            # This is fixed in https://gitlab.com/gitlab-org/gitlab_git/merge_requests/52
+            @commits = @project.repository.commits_between(common_ref, @newrev) if common_ref
+          rescue => e
+          end
+
+          # Prevent system notes from seeing a blank SHA
+          @oldrev = nil
+        end
+
         SystemNoteService.change_branch_presence(
             merge_request, merge_request.project, @current_user,
             :source, @branch_name, presence)

From bf290a52b7589ccd0e37a224ec36cec28acfb6a8 Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Thu, 15 Oct 2015 23:19:34 -0700
Subject: [PATCH 6/8] Rubocop fix

---
 app/services/merge_requests/refresh_service.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index 7c4cb35ec6..c378f14c26 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -94,7 +94,7 @@ module MergeRequests
             # gitlab_git throws a Rugged::OdbError
             # This is fixed in https://gitlab.com/gitlab-org/gitlab_git/merge_requests/52
             @commits = @project.repository.commits_between(common_ref, @newrev) if common_ref
-          rescue => e
+          rescue
           end
 
           # Prevent system notes from seeing a blank SHA

From 888c1a3fc53ff0318cd69d0e7f1edad25f306713 Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Fri, 16 Oct 2015 00:25:19 -0700
Subject: [PATCH 7/8] Add spec for refresh service adding notes to restored
 branches

---
 .../merge_requests/refresh_service.rb         |  5 ++--
 .../merge_requests/refresh_service_spec.rb    | 24 ++++++++++---------
 spec/services/system_note_service_spec.rb     |  4 ++--
 3 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/app/services/merge_requests/refresh_service.rb b/app/services/merge_requests/refresh_service.rb
index c378f14c26..121f689901 100644
--- a/app/services/merge_requests/refresh_service.rb
+++ b/app/services/merge_requests/refresh_service.rb
@@ -90,9 +90,8 @@ module MergeRequests
             # Since any number of commits could have been made to the restored branch,
             # find the common root to see what has been added.
             common_ref = @project.repository.merge_base(last_commit.id, @newrev)
-            # If the last_commit no longer exists in this new branch,
-            # gitlab_git throws a Rugged::OdbError
-            # This is fixed in https://gitlab.com/gitlab-org/gitlab_git/merge_requests/52
+            # If the a commit no longer exists in this repo, gitlab_git throws
+            # a Rugged::OdbError. This is fixed in https://gitlab.com/gitlab-org/gitlab_git/merge_requests/52
             @commits = @project.repository.commits_between(common_ref, @newrev) if common_ref
           rescue
           end
diff --git a/spec/services/merge_requests/refresh_service_spec.rb b/spec/services/merge_requests/refresh_service_spec.rb
index 41eb5d41b2..463cd594fb 100644
--- a/spec/services/merge_requests/refresh_service_spec.rb
+++ b/spec/services/merge_requests/refresh_service_spec.rb
@@ -108,21 +108,23 @@ describe MergeRequests::RefreshService do
 
     context 'push new branch that exists in a merge request' do
       let(:refresh_service) { service.new(@fork_project, @user) }
-      before do
-        allow(refresh_service).to receive(:execute_hooks)
+
+      it 'refreshes the merge request' do
+        expect(refresh_service).to receive(:execute_hooks).
+                                       with(@fork_merge_request, 'update')
+        allow_any_instance_of(Repository).to receive(:merge_base).and_return(@oldrev)
+
         refresh_service.execute(Gitlab::Git::BLANK_SHA, @newrev, 'refs/heads/master')
         reload_mrs
-      end
 
-      it 'should execute hooks with update action' do
-        expect(refresh_service).to have_received(:execute_hooks).
-                                       with(@fork_merge_request, 'update')
-      end
+        expect(@merge_request.notes).to be_empty
+        expect(@merge_request).to be_open
 
-      it { expect(@merge_request.notes).to be_empty }
-      it { expect(@merge_request).to be_open }
-      it { expect(@fork_merge_request.notes.last.note).to include('Source branch `master` restored') }
-      it { expect(@fork_merge_request).to be_open }
+        notes = @fork_merge_request.notes.reorder(:created_at).map(&:note)
+        expect(notes[0]).to include('Source branch `master` restored')
+        expect(notes[1]).to include('Added 4 commits')
+        expect(@fork_merge_request).to be_open
+      end
     end
 
     def reload_mrs
diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index 16b1c66ff9..699b2e3441 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -229,7 +229,7 @@ describe SystemNoteService do
   end
 
   describe '.change_branch' do
-    subject { described_class.change_branch(noteable, project, author, :target, old_branch, new_branch) }
+    subject { described_class.change_branch(noteable, project, author, 'target', old_branch, new_branch) }
     let(:old_branch) { 'old_branch'}
     let(:new_branch) { 'new_branch'}
 
@@ -243,7 +243,7 @@ describe SystemNoteService do
   end
 
   describe '.change_branch_presence' do
-    subject { described_class.change_branch_presence(noteable, project, author, 'source', 'feature', :delete) }
+    subject { described_class.change_branch_presence(noteable, project, author, :source, 'feature', :delete) }
 
     it_behaves_like 'a system note'
 

From f726df26c28666e640e566d50f363994e71cf681 Mon Sep 17 00:00:00 2001
From: Stan Hu <stanhu@gmail.com>
Date: Fri, 16 Oct 2015 00:51:25 -0700
Subject: [PATCH 8/8] Reorder system note verb to say "Restored source branch
 X" instead of "Source branch X restored"

---
 app/services/system_note_service.rb                  | 4 ++--
 spec/services/merge_requests/refresh_service_spec.rb | 2 +-
 spec/services/system_note_service_spec.rb            | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/app/services/system_note_service.rb b/app/services/system_note_service.rb
index c0a5c3aeb5..37f454cfc3 100644
--- a/app/services/system_note_service.rb
+++ b/app/services/system_note_service.rb
@@ -179,7 +179,7 @@ class SystemNoteService
   #
   # Example Note text:
   #
-  #   "Target branch `feature` deleted"
+  #   "Restored target branch `feature`"
   #
   # Returns the created Note object
   def self.change_branch_presence(noteable, project, author, branch_type, branch, presence)
@@ -189,7 +189,7 @@ class SystemNoteService
       else
         'deleted'
       end
-    body = "#{branch_type.to_s} branch `#{branch}` #{verb}".capitalize
+    body = "#{verb} #{branch_type.to_s} branch `#{branch}`".capitalize
     create_note(noteable: noteable, project: project, author: author, note: body)
   end
 
diff --git a/spec/services/merge_requests/refresh_service_spec.rb b/spec/services/merge_requests/refresh_service_spec.rb
index 463cd594fb..227ac995ec 100644
--- a/spec/services/merge_requests/refresh_service_spec.rb
+++ b/spec/services/merge_requests/refresh_service_spec.rb
@@ -121,7 +121,7 @@ describe MergeRequests::RefreshService do
         expect(@merge_request).to be_open
 
         notes = @fork_merge_request.notes.reorder(:created_at).map(&:note)
-        expect(notes[0]).to include('Source branch `master` restored')
+        expect(notes[0]).to include('Restored source branch `master`')
         expect(notes[1]).to include('Added 4 commits')
         expect(@fork_merge_request).to be_open
       end
diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index 699b2e3441..a45130bd47 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -249,7 +249,7 @@ describe SystemNoteService do
 
     context 'when source branch deleted' do
       it 'sets the note text' do
-        expect(subject.note).to eq "Source branch `feature` deleted"
+        expect(subject.note).to eq "Deleted source branch `feature`"
       end
     end
   end