Add a benchmark for precompleted context creation

diff --git a/context_test.go b/context_test.go
index a7b30a4..0fa10d7 100644 (file)
--- a/context_test.go
+++ b/context_test.go
@@ -64,7 +64,7 @@ func TestCancelAfterSignal(t *testing.T) {
        assert.Equal(t, Error{syscall.SIGUSR2}, ctx.Err())
 }
 
-func TestImmediateCompletion(t *testing.T) {
+func TestPrecompleted(t *testing.T) {
        parent, cancel := context.WithCancel(context.Background())
        cancel()
        <-parent.Done()
@@ -120,3 +120,14 @@ func BenchmarkCanceledAsChild(b *testing.B) {
                <-children[i].Done()
        }
 }
+
+func BenchmarkPrecompleted(b *testing.B) {
+       parent, cancel := context.WithCancel(context.Background())
+       cancel()
+       <-parent.Done()
+       b.ResetTimer()
+       for i := 0; i < b.N; i++ {
+               ctx := UntilSignal(parent, syscall.SIGUSR2)
+               <-ctx.Done()
+       }
+}