1 files changed, 87 insertions, 0 deletions
diff --git a/spec/lib/gitlab/graphql/calls_gitaly/field_extension_spec.rb b/spec/lib/gitlab/graphql/calls_gitaly/field_extension_spec.rb
new file mode 100644
index 00000000000..1d8849f7e38
--- /dev/null
+++ b/spec/lib/gitlab/graphql/calls_gitaly/field_extension_spec.rb
@@ -0,0 +1,87 @@
+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe Gitlab::Graphql::CallsGitaly::FieldExtension, :request_store do
+  include GraphqlHelpers
+
+  let(:field_args) { {} }
+  let(:owner) { fresh_object_type }
+  let(:field) do
+    ::Types::BaseField.new(name: 'value', type: GraphQL::STRING_TYPE, null: true, owner: owner, **field_args)
+  end
+
+  def resolve_value
+    resolve_field(field, { value: 'foo' }, object_type: owner)
+  end
+
+  context 'when the field calls gitaly' do
+    before do
+      owner.define_method :value do
+        Gitlab::SafeRequestStore['gitaly_call_actual'] = 1
+        'fresh-from-the-gitaly-mines!'
+      end
+    end
+
+    context 'when the field has a constant complexity' do
+      let(:field_args) { { complexity: 100 } }
+
+      it 'allows the call' do
+        expect { resolve_value }.not_to raise_error
+      end
+    end
+
+    context 'when the field declares that it calls gitaly' do
+      let(:field_args) { { calls_gitaly: true } }
+
+      it 'allows the call' do
+        expect { resolve_value }.not_to raise_error
+      end
+    end
+
+    context 'when the field does not have these arguments' do
+      let(:field_args) { {} }
+
+      it 'notices, and raises, mentioning the field' do
+        expect { resolve_value }.to raise_error(include('Object.value'))
+      end
+    end
+  end
+
+  context 'when it does not call gitaly' do
+    let(:field_args) { {} }
+
+    it 'does not raise' do
+      value = resolve_value
+
+      expect(value).to eq 'foo'
+    end
+  end
+
+  context 'when some field calls gitaly while we were waiting' do
+    let(:extension) { described_class.new(field: field, options: {}) }
+
+    it 'is acceptable if all are accounted for' do
+      object = :anything
+      arguments = :any_args
+
+      ::Gitlab::SafeRequestStore['gitaly_call_actual'] = 3
+      ::Gitlab::SafeRequestStore['graphql_gitaly_accounted_for'] = 0
+
+      expect do |b|
+        extension.resolve(object: object, arguments: arguments, &b)
+      end.to yield_with_args(object, arguments, [3, 0])
+
+      ::Gitlab::SafeRequestStore['gitaly_call_actual'] = 13
+      ::Gitlab::SafeRequestStore['graphql_gitaly_accounted_for'] = 10
+
+      expect { extension.after_resolve(value: 'foo', memo: [3, 0]) }.not_to raise_error
+    end
+
+    it 'is unacceptable if some of the calls are unaccounted for' do
+      ::Gitlab::SafeRequestStore['gitaly_call_actual'] = 10
+      ::Gitlab::SafeRequestStore['graphql_gitaly_accounted_for'] = 9
+
+      expect { extension.after_resolve(value: 'foo', memo: [0, 0]) }.to raise_error(include('Object.value'))
+    end
+  end
+end