cmd/go: go test -timeout flag behavior doesn't match test binary -timeout flag behavior

[josharian]

Running a test binary with -h prints:

  -test.timeout d
    	fail test binary execution after duration d (0 means unlimited)

But that doesn't seem to work:

package p

import (
	"testing"
	"time"
)

func BenchmarkSlow(b *testing.B) {
	for i := 0; i < b.N; i++ {
		time.Sleep(15 * time.Minute)
	}
}

Running this with go test -bench=. -timeout=0 x_test.go results (eventually) in *** Test killed with quit: ran too long (10m0s).

[josharian]

Ick. Looks like this is implemented correctly in package testing, but that this timeout comes from 'go test', so to disable timeouts you need to use 'go test -c' and then execute. It'd be much nicer if test binaries and cmd/go agreed on behavior, and there was a way to disable timeouts directly via 'go test'.

I guess a workaround is 'go test -timeout=1000h'.

[ianlancetaylor]

It's really just a bug in cmd/go. Explicitly passing -test.timeout=0 should disable testKillTimeout in cmd/go/internal/test/test.go.

In fact this is #18490.

[ianlancetaylor]

And I have to respect the fact that you did a thumbs up on my suggestion in #18490 which would also fix this issue....

[josharian]

Hahaha. My mental github issue index clearly failed me. Thanks, Ian. :)