Merge branch 'fix/commit-no-repo-error' into 'master'

Fix broken repo error raised after requesting a commit

Prevents a 500 error on screen after `Rugged::RepositoryError: Could not find repository from '/var/opt/gitlab/git-data/repositories/user/project.git'`, which could happen when checking for the last commit in the list of projects (dashboard).

Related https://gitlab.com/gitlab-org/gitlab-ce/issues/20501

See merge request !124

CHANGELOG

+v 10.6.7
+  - Commit.find returns nil and no longer throws an error on an empty repository
+
 v 10.6.6
   - The Git attributes parser can now parse file paths without any attributes

VERSION

-10.6.6
+10.6.7

lib/gitlab_git/commit.rb

@@ -64,7 +64,7 @@ module Gitlab
           return nil unless obj.is_a?(Rugged::Commit)
           decorate(obj)
-        rescue Rugged::ReferenceError, Rugged::InvalidError, Rugged::ObjectError
+        rescue Rugged::ReferenceError, Rugged::InvalidError, Rugged::ObjectError, Gitlab::Git::Repository::NoRepository
           nil
         end

spec/commit_spec.rb

@@ -93,6 +93,14 @@ describe Gitlab::Git::Commit do
       it "should return nil for nonexisting ids" do
         expect(Gitlab::Git::Commit.find(repository, "+123_4532530XYZ")).to be_nil
       end
+
+      context 'with broken repo' do
+        let(:repository) { Gitlab::Git::Repository.new(TEST_BROKEN_REPO_PATH) }
+
+        it 'returns nil' do
+          expect(Gitlab::Git::Commit.find(repository, SeedRepo::Commit::ID)).to be_nil
+        end
+      end
     end
     describe :last_for_path do

spec/spec_helper.rb

@@ -33,6 +33,7 @@ SUPPORT_PATH = File.join(File.expand_path(File.dirname(__FILE__)), '../support')
 TEST_REPO_PATH = File.join(SUPPORT_PATH, 'gitlab-git-test.git')
 TEST_NORMAL_REPO_PATH = File.join(SUPPORT_PATH, "not-bare-repo.git")
 TEST_MUTABLE_REPO_PATH = File.join(SUPPORT_PATH, "mutable-repo.git")
+TEST_BROKEN_REPO_PATH = File.join(SUPPORT_PATH, "broken-repo.git")
 RSpec.configure do |config|
   config.run_all_when_everything_filtered = true

spec/support/seed_helper.rb

@@ -11,6 +11,7 @@ module SeedHelper
     create_bare_seeds
     create_normal_seeds
     create_mutable_seeds
+    create_broken_seeds
     create_git_attributes
   end
@@ -39,6 +40,16 @@ module SeedHelper
            chdir: TEST_MUTABLE_REPO_PATH, out: '/dev/null', err: '/dev/null')
   end
+  def create_broken_seeds
+    system(git_env, *%W(git clone --bare #{TEST_REPO_PATH} #{TEST_BROKEN_REPO_PATH}),
+           out: '/dev/null',
+           err: '/dev/null')
+
+    refs_path = File.join(TEST_BROKEN_REPO_PATH, 'refs')
+
+    FileUtils.rm_r(refs_path)
+  end
+
   def create_git_attributes
     dir = File.join(SUPPORT_PATH, 'with-git-attributes.git', 'info')