tailscale/tstest/resource.go
Josh Bleecher Snyder e8cd7bb66f tstest: simplify goroutine leak tests
Use tb.Cleanup to simplify both the API and the implementation.

One behavior change: When the number of goroutines shrinks, don't log.
I've never found these logs to be useful, and they frequently add noise.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-02-03 13:06:40 -08:00

44 lines
945 B
Go

// Copyright (c) 2020 Tailscale Inc & 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 tstest
import (
"bytes"
"runtime"
"runtime/pprof"
"testing"
"time"
"github.com/google/go-cmp/cmp"
)
func ResourceCheck(tb testing.TB) {
startN, startStacks := goroutines()
tb.Cleanup(func() {
if tb.Failed() {
// Something else went wrong.
return
}
tb.Helper()
// Goroutines might be still exiting.
for i := 0; i < 100; i++ {
if runtime.NumGoroutine() <= startN {
return
}
time.Sleep(1 * time.Millisecond)
}
endN, endStacks := goroutines()
tb.Logf("goroutine diff:\n%v\n", cmp.Diff(startStacks, endStacks))
tb.Fatalf("goroutine count: expected %d, got %d\n", startN, endN)
})
}
func goroutines() (int, []byte) {
p := pprof.Lookup("goroutine")
b := new(bytes.Buffer)
p.WriteTo(b, 1)
return p.Count(), b.Bytes()
}