internal/stack: add the leak test
This adds a package for dealing with stacks in tests.
The only function at this time is NoLeak which verifies that a test
does not leak any goroutines, and prints a stack summary if it does.
Change-Id: I284b846f422334b745bef0e96d84138295120a62
Reviewed-on: https://go-review.googlesource.com/c/tools/+/232681
Run-TryBot: Ian Cottrell <iancottrell@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
diff --git a/internal/jsonrpc2/jsonrpc2_test.go b/internal/jsonrpc2/jsonrpc2_test.go
index 072f1d5..e586009 100644
--- a/internal/jsonrpc2/jsonrpc2_test.go
+++ b/internal/jsonrpc2/jsonrpc2_test.go
@@ -18,6 +18,7 @@
"golang.org/x/tools/internal/event/export/eventtest"
"golang.org/x/tools/internal/jsonrpc2"
+ "golang.org/x/tools/internal/stack/stacktest"
)
var logRPC = flag.Bool("logrpc", false, "Enable jsonrpc2 communication logging")
@@ -62,6 +63,7 @@
}
func TestCall(t *testing.T) {
+ stacktest.NoLeak(t)
ctx := eventtest.NewContext(context.Background(), t)
for _, headers := range []bool{false, true} {
name := "Plain"
diff --git a/internal/jsonrpc2/serve_test.go b/internal/jsonrpc2/serve_test.go
index 1b95610..c9c1fbd 100644
--- a/internal/jsonrpc2/serve_test.go
+++ b/internal/jsonrpc2/serve_test.go
@@ -10,9 +10,12 @@
"sync"
"testing"
"time"
+
+ "golang.org/x/tools/internal/stack/stacktest"
)
func TestIdleTimeout(t *testing.T) {
+ stacktest.NoLeak(t)
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()
diff --git a/internal/stack/stacktest/stacktest.go b/internal/stack/stacktest/stacktest.go
new file mode 100644
index 0000000..e23f03e
--- /dev/null
+++ b/internal/stack/stacktest/stacktest.go
@@ -0,0 +1,50 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package stacktest
+
+import (
+ "testing"
+ "time"
+
+ "golang.org/x/tools/internal/stack"
+)
+
+//this is only needed to support pre 1.14 when testing.TB did not have Cleanup
+type withCleanup interface {
+ Cleanup(func())
+}
+
+// the maximum amount of time to wait for goroutines to clean themselves up.
+const maxWait = time.Second
+
+// NoLeak checks that a test (or benchmark) does not leak any goroutines.
+func NoLeak(t testing.TB) {
+ c, ok := t.(withCleanup)
+ if !ok {
+ return
+ }
+ before := stack.Capture()
+ c.Cleanup(func() {
+ var delta stack.Delta
+ start := time.Now()
+ delay := time.Millisecond
+ for {
+ after := stack.Capture()
+ delta = stack.Diff(before, after)
+ if len(delta.After) == 0 {
+ // no leaks
+ return
+ }
+ if time.Since(start) > maxWait {
+ break
+ }
+ time.Sleep(delay)
+ delay *= 2
+ }
+ // it's been long enough, and leaks are still present
+ summary := stack.Summarize(delta.After)
+ t.Errorf("goroutine leak detected:\n%+v", summary)
+ })
+}
