testing: is the package thread-safe?

[matthewmueller]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version go1.8.3 darwin/amd64

What operating system and processor architecture are you using (go env)?

GOHOSTARCH="amd64"
GOHOSTOS="darwin"

What did you do?

Running t.Fatal(err) inside multiple goroutines with the -race flag

What did you expect to see?

The testing package to be thread-safe and not report data races when running the -race flag.

I'm not 100% sure this isn't related to my code, but based on the error I think it's because I'm calling t.Fatal(err) from multiple goroutines. So I'd just like some clarity there.

What did you see instead?

Write at 0x00c42014e524 by goroutine 10:
  testing.tRunner()
      /usr/local/go/src/testing/testing.go:658 +0x119

Previous write at 0x00c42014e524 by goroutine 62:
  testing.(*common).FailNow()
      /usr/local/go/src/testing/testing.go:485 +0x4a
  testing.(*common).Fatal()
      /usr/local/go/src/testing/testing.go:524 +0x7c
  command-line-arguments_test.TestPageSetControlNavigations.func1()
      /Users/matt/go/src/github.com/api/api_test.go:241 +0x2d3

[ALTree]

This is documented:

A test ends when its Test function returns or calls any of the methods FailNow, Fatal, Fatalf, SkipNow, Skip, or Skipf. Those methods, as well as the Parallel method, must be called only from the goroutine running the Test function.

http://tip.golang.org/pkg/testing/#T

Closing this, since it's not a bug.

[matthewmueller]

Ahh there it is. Thanks!