Merge branch 'bvl-unlink-fixes' into 'master'

This fixes some bugs related to forked projects of which the source was deleted.

Closes #39667

See merge request gitlab-org/gitlab-ce!15150

14 files changed, 182 insertions, 18 deletions

diff --git a/app/controllers/concerns/lfs_request.rb b/app/controllers/concerns/lfs_request.rb
index 2b6afaa6233..738afd612f0 100644
--- a/app/controllers/concerns/lfs_request.rb
+++ b/app/controllers/concerns/lfs_request.rb
@@ -94,10 +94,9 @@ module LfsRequest
     @storage_project ||= begin
       result = project
 
-      loop do
-        break unless result.forked?
-        result = result.forked_from_project
-      end
+      # TODO: Make this go to the fork_network root immeadiatly
+      # dependant on the discussion in: https://gitlab.com/gitlab-org/gitlab-ce/issues/39769
+      result = result.fork_source while result.forked?
 
       result
     end
diff --git a/app/helpers/projects_helper.rb b/app/helpers/projects_helper.rb
index 20e050195ea..d21c01cc27f 100644
--- a/app/helpers/projects_helper.rb
+++ b/app/helpers/projects_helper.rb
@@ -97,7 +97,15 @@ module ProjectsHelper
 
   def remove_fork_project_message(project)
     _("You are going to remove the fork relationship to source project %{forked_from_project}. Are you ABSOLUTELY sure?") %
-      { forked_from_project: @project.forked_from_project.name_with_namespace }
+      { forked_from_project: fork_source_name(project) }
+  end
+
+  def fork_source_name(project)
+    if @project.fork_source
+      @project.fork_source.full_name
+    else
+      @project.fork_network&.deleted_root_project_name
+    end
   end
 
   def project_nav_tabs
@@ -127,8 +135,8 @@ module ProjectsHelper
   def can_change_visibility_level?(project, current_user)
     return false unless can?(current_user, :change_visibility_level, project)
 
-    if project.forked?
-      project.forked_from_project.visibility_level > Gitlab::VisibilityLevel::PRIVATE
+    if project.fork_source
+      project.fork_source.visibility_level > Gitlab::VisibilityLevel::PRIVATE
     else
       true
     end
diff --git a/app/models/fork_network.rb b/app/models/fork_network.rb
index 218e37a5312..7f1728e8c77 100644
--- a/app/models/fork_network.rb
+++ b/app/models/fork_network.rb
@@ -12,4 +12,8 @@ class ForkNetwork < ActiveRecord::Base
   def find_forks_in(other_projects)
     projects.where(id: other_projects)
   end
+
+  def merge_requests
+    MergeRequest.where(target_project: projects)
+  end
 end
diff --git a/app/models/project.rb b/app/models/project.rb
index 984ef015f4a..4ee6db9211f 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -1017,6 +1017,10 @@ class Project < ActiveRecord::Base
     !(forked_project_link.nil? || forked_project_link.forked_from_project.nil?)
   end
 
+  def fork_source
+    forked_from_project || fork_network&.root_project
+  end
+
   def personal?
     !group
   end
diff --git a/app/services/projects/unlink_fork_service.rb b/app/services/projects/unlink_fork_service.rb
index 2b82e5732e4..c499f384426 100644
--- a/app/services/projects/unlink_fork_service.rb
+++ b/app/services/projects/unlink_fork_service.rb
@@ -3,18 +3,24 @@ module Projects
     def execute
       return unless @project.forked?
 
-      @project.forked_from_project.lfs_objects.find_each do |lfs_object|
-        lfs_object.projects << @project
+      if fork_source = @project.fork_source
+        fork_source.lfs_objects.find_each do |lfs_object|
+          lfs_object.projects << @project
+        end
+
+        refresh_forks_count(fork_source)
       end
 
-      merge_requests = @project.forked_from_project.merge_requests.opened.from_project(@project)
+      merge_requests = @project.fork_network
+                         .merge_requests
+                         .opened
+                         .where.not(target_project: @project)
+                         .from_project(@project)
 
       merge_requests.each do |mr|
         ::MergeRequests::CloseService.new(@project, @current_user).execute(mr)
       end
 
-      refresh_forks_count(@project.forked_from_project)
-
       @project.fork_network_member.destroy
       @project.forked_project_link.destroy
     end
diff --git a/app/views/projects/_home_panel.html.haml b/app/views/projects/_home_panel.html.haml
index 619b632918e..1d644dda177 100644
--- a/app/views/projects/_home_panel.html.haml
+++ b/app/views/projects/_home_panel.html.haml
@@ -1,6 +1,5 @@
 - empty_repo = @project.empty_repo?
 - fork_network = @project.fork_network
-- forked_from_project = @project.forked_from_project || fork_network&.root_project
 .project-home-panel.text-center{ class: ("empty-project" if empty_repo) }
   .limit-container-width{ class: container_class }
     .avatar-container.s70.project-avatar
@@ -16,13 +15,13 @@
 
       - if @project.forked?
         %p
-          - if forked_from_project
+          - if @project.fork_source
             #{ s_('ForkedFromProjectPath|Forked from') }
-            = link_to project_path(forked_from_project) do
-              = forked_from_project.full_name
+            = link_to project_path(@project.fork_source) do
+              = fork_source_name(@project)
           - else
             - deleted_message = s_('ForkedFromProjectPath|Forked from %{project_name} (deleted)')
-            = deleted_message % { project_name: fork_network.deleted_root_project_name }
+            = deleted_message % { project_name: fork_source_name(@project) }
 
     .project-repo-buttons
       .count-buttons
diff --git a/app/views/projects/edit.html.haml b/app/views/projects/edit.html.haml
index 5703ef1d4bb..5ebeae5c35f 100644
--- a/app/views/projects/edit.html.haml
+++ b/app/views/projects/edit.html.haml
@@ -173,7 +173,10 @@
           %p
             This will remove the fork relationship to source project
             = succeed "." do
-              = link_to @project.forked_from_project.name_with_namespace, project_path(@project.forked_from_project)
+              - if @project.fork_source
+                = link_to(fork_source_name(@project), project_path(@project.fork_source))
+              - else
+                = fork_source_name(@project)
           = form_for([@project.namespace.becomes(Namespace), @project], url: remove_fork_project_path(@project), method: :delete, remote: true, html: { class: 'transfer-project' }) do |f|
             %p
               %strong Once removed, the fork relationship cannot be restored and you will no longer be able to send merge requests to the source.
diff --git a/changelogs/unreleased/bvl-unlink-fixes.yml b/changelogs/unreleased/bvl-unlink-fixes.yml
new file mode 100644
index 00000000000..685d78f479d
--- /dev/null
+++ b/changelogs/unreleased/bvl-unlink-fixes.yml
@@ -0,0 +1,5 @@
+---
+title: Fix issues with forked projects of which the source was deleted
+merge_request: 15150
+author:
+type: fixed
diff --git a/spec/controllers/concerns/lfs_request_spec.rb b/spec/controllers/concerns/lfs_request_spec.rb
new file mode 100644
index 00000000000..33b23db302a
--- /dev/null
+++ b/spec/controllers/concerns/lfs_request_spec.rb
@@ -0,0 +1,50 @@
+require 'spec_helper'
+
+describe LfsRequest do
+  include ProjectForksHelper
+
+  controller(Projects::GitHttpClientController) do
+    # `described_class` is not available in this context
+    include LfsRequest # rubocop:disable RSpec/DescribedClass
+
+    def show
+      storage_project
+
+      render nothing: true
+    end
+
+    def project
+      @project ||= Project.find(params[:id])
+    end
+
+    def download_request?
+      true
+    end
+
+    def ci?
+      false
+    end
+  end
+
+  let(:project) { create(:project, :public) }
+
+  before do
+    stub_lfs_setting(enabled: true)
+  end
+
+  describe '#storage_project' do
+    it 'assigns the project as storage project' do
+      get :show, id: project.id
+
+      expect(assigns(:storage_project)).to eq(project)
+    end
+
+    it 'assigns the source of a forked project' do
+      forked_project = fork_project(project)
+
+      get :show, id: forked_project.id
+
+      expect(assigns(:storage_project)).to eq(project)
+    end
+  end
+end
diff --git a/spec/features/projects/settings/forked_project_settings_spec.rb b/spec/features/projects/settings/forked_project_settings_spec.rb
new file mode 100644
index 00000000000..28954a4fb40
--- /dev/null
+++ b/spec/features/projects/settings/forked_project_settings_spec.rb
@@ -0,0 +1,40 @@
+require 'spec_helper'
+
+feature 'Settings for a forked project', :js do
+  include ProjectForksHelper
+  let(:user) { create(:user) }
+  let(:original_project) { create(:project) }
+  let(:forked_project) { fork_project(original_project, user) }
+
+  before do
+    original_project.add_master(user)
+    forked_project.add_master(user)
+    sign_in(user)
+  end
+
+  shared_examples 'project settings for a forked projects' do
+    it 'allows deleting the link to the forked project' do
+      visit edit_project_path(forked_project)
+
+      click_button 'Remove fork relationship'
+
+      wait_for_requests
+
+      fill_in('confirm_name_input', with: forked_project.name)
+      click_button('Confirm')
+
+      expect(page).to have_content('The fork relationship has been removed.')
+      expect(forked_project.reload.forked?).to be_falsy
+    end
+  end
+
+  it_behaves_like 'project settings for a forked projects'
+
+  context 'when the original project is deleted' do
+    before do
+      original_project.destroy!
+    end
+
+    it_behaves_like 'project settings for a forked projects'
+  end
+end
diff --git a/spec/models/fork_network_spec.rb b/spec/models/fork_network_spec.rb
index 605ccd6db06..a43baf1820a 100644
--- a/spec/models/fork_network_spec.rb
+++ b/spec/models/fork_network_spec.rb
@@ -24,6 +24,16 @@ describe ForkNetwork do
     end
   end
 
+  describe '#merge_requests' do
+    it 'finds merge requests within the fork network' do
+      project = create(:project)
+      forked_project = fork_project(project)
+      merge_request = create(:merge_request, source_project: forked_project, target_project: project)
+
+      expect(project.fork_network.merge_requests).to include(merge_request)
+    end
+  end
+
   context 'for a deleted project' do
     it 'keeps the fork network' do
       project = create(:project, :public)
diff --git a/spec/models/project_spec.rb b/spec/models/project_spec.rb
index cf26dbfea49..83be9642437 100644
--- a/spec/models/project_spec.rb
+++ b/spec/models/project_spec.rb
@@ -1907,6 +1907,20 @@ describe Project do
         expect(forked_project.in_fork_network_of?(other_project)).to be_falsy
       end
     end
+
+    describe '#fork_source' do
+      let!(:second_fork) { fork_project(forked_project) }
+
+      it 'returns the direct source if it exists' do
+        expect(second_fork.fork_source).to eq(forked_project)
+      end
+
+      it 'returns the root of the fork network when the directs source was deleted' do
+        forked_project.destroy
+
+        expect(second_fork.fork_source).to eq(project)
+      end
+    end
   end
 
   describe '#pushes_since_gc' do
diff --git a/spec/services/projects/unlink_fork_service_spec.rb b/spec/services/projects/unlink_fork_service_spec.rb
index 50d3a4ec982..2bba71fef4f 100644
--- a/spec/services/projects/unlink_fork_service_spec.rb
+++ b/spec/services/projects/unlink_fork_service_spec.rb
@@ -12,6 +12,9 @@ describe Projects::UnlinkForkService do
 
   context 'with opened merge request on the source project' do
     let(:merge_request) { create(:merge_request, source_project: forked_project, target_project: fork_link.forked_from_project) }
+    let(:merge_request2) { create(:merge_request, source_project: forked_project, target_project: fork_project(project)) }
+    let(:merge_request_in_fork) { create(:merge_request, source_project: forked_project, target_project: forked_project) }
+
     let(:mr_close_service) { MergeRequests::CloseService.new(forked_project, user) }
 
     before do
@@ -22,9 +25,14 @@ describe Projects::UnlinkForkService do
 
     it 'close all pending merge requests' do
       expect(mr_close_service).to receive(:execute).with(merge_request)
+      expect(mr_close_service).to receive(:execute).with(merge_request2)
 
       subject.execute
     end
+
+    it 'does not close merge requests for the project being unlinked' do
+      expect(mr_close_service).not_to receive(:execute).with(merge_request_in_fork)
+    end
   end
 
   it 'remove fork relation' do
@@ -53,4 +61,14 @@ describe Projects::UnlinkForkService do
 
     expect(source.forks_count).to be_zero
   end
+
+  context 'when the original project was deleted' do
+    it 'does not fail when the original project is deleted' do
+      source = forked_project.forked_from_project
+      source.destroy
+      forked_project.reload
+
+      expect { subject.execute }.not_to raise_error
+    end
+  end
 end
diff --git a/spec/support/stub_configuration.rb b/spec/support/stub_configuration.rb
index 4d448a55978..4ead78529c3 100644
--- a/spec/support/stub_configuration.rb
+++ b/spec/support/stub_configuration.rb
@@ -38,6 +38,10 @@ module StubConfiguration
     allow(Gitlab.config.backup).to receive_messages(to_settings(messages))
   end
 
+  def stub_lfs_setting(messages)
+    allow(Gitlab.config.lfs).to receive_messages(to_settings(messages))
+  end
+
   def stub_storage_settings(messages)
     # Default storage is always required
     messages['default'] ||= Gitlab.config.repositories.storages.default