Merge branch 'fix_no_method_error_when_commit_is_missing' into 'master'

Fix NoMethodError when commit is missing

See merge request gitlab-org/gitlab!79553

app/controllers/projects/commit_controller.rb

@@ -92,6 +92,8 @@ class Projects::CommitController < Projects::ApplicationController
   end
 
   def branches
+    return git_not_found! unless commit
+
     # branch_names_contains/tag_names_contains can take a long time when there are thousands of
     # branches/tags - each `git branch --contains xxx` request can consume a cpu core.
     # so only do the query when there are a manageable number of branches/tags

spec/controllers/projects/commit_controller_spec.rb

@@ -183,6 +183,18 @@ RSpec.describe Projects::CommitController do
       expect(assigns(:tags)).to eq([])
       expect(assigns(:tags_limit_exceeded)).to be_truthy
     end
+
+    context 'when commit is not found' do
+      it 'responds with 404' do
+        get(:branches, params: {
+          namespace_id: project.namespace,
+          project_id: project,
+          id: '11111111111111111111111111111111111111'
+        })
+
+        expect(response).to be_not_found
+      end
+    end
   end
 
   describe 'POST revert' do