Merge branch '58613-protected-branches-error' into 'master'

Allow protected branch creation for empty project

Closes #58613

See merge request gitlab-org/gitlab-ce!25834

lib/gitlab/checks/branch_check.rb

@@ -46,7 +46,9 @@ module Gitlab
           end
         end
 
-        if creation? && protected_branch_creation_enabled?
+        if project.empty_repo?
+          protected_branch_push_checks
+        elsif creation? && protected_branch_creation_enabled?
           protected_branch_creation_checks
         elsif deletion?
           protected_branch_deletion_checks

spec/lib/gitlab/checks/branch_check_spec.rb

@@ -48,13 +48,31 @@ describe Gitlab::Checks::BranchCheck do
       context 'when project repository is empty' do
         let(:project) { create(:project) }
 
-        it 'raises an error if the user is not allowed to push to protected branches' do
-          expect(user_access).to receive(:can_push_to_branch?).and_return(false)
+        context 'user is not allowed to push to protected branches' do
+          before do
+            allow(user_access)
+              .to receive(:can_push_to_branch?)
+              .and_return(false)
+          end
 
+          it 'raises an error' do
             expect { subject.validate! }.to raise_error(Gitlab::GitAccess::UnauthorizedError, /Ask a project Owner or Maintainer to create a default branch/)
           end
         end
 
+        context 'user is allowed to push to protected branches' do
+          before do
+            allow(user_access)
+              .to receive(:can_push_to_branch?)
+              .and_return(true)
+          end
+
+          it 'allows branch creation' do
+            expect { subject.validate! }.not_to raise_error
+          end
+        end
+      end
+
       context 'branch creation' do
         let(:oldrev) { '0000000000000000000000000000000000000000' }
         let(:ref) { 'refs/heads/feature' }