cmd/go: in TestScript, set GOTRACEBACK and use SIGQUIT to terminate hung subprocesses

This should produce more useful outputs if a cmd/go invocation hangs
during a test.

(In some cases the outputs will be very verbose, but verbose is still
better than uninformative.)

For #36460
For #38768

Change-Id: Ibaf2d0fbf7387dfab1aad8981140ecb11901fc4b
Reviewed-on: https://go-review.googlesource.com/c/go/+/308809
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>

diff --git a/src/cmd/go/script_test.go b/src/cmd/go/script_test.go
index c353a9cb015784b4a0aa5541d8366f79a4f74e06..20d0f956a7fd13d3632015c7cb26bdc14e4bba93 100644 (file)
--- a/src/cmd/go/script_test.go
+++ b/src/cmd/go/script_test.go
@@ -172,6 +172,7 @@ func (ts *testScript) setup() {
                "GOPRIVATE=",
                "GOROOT=" + testGOROOT,
                "GOROOT_FINAL=" + os.Getenv("GOROOT_FINAL"), // causes spurious rebuilds and breaks the "stale" built-in if not propagated
+               "GOTRACEBACK=all",
                "TESTGO_GOROOT=" + testGOROOT,
                "GOSUMDB=" + testSumDBVerifierKey,
                "GONOPROXY=",
@@ -1120,24 +1121,12 @@ func (ts *testScript) startBackground(want simpleStatus, command string, args ..
        }
 
        go func() {
-               bg.err = waitOrStop(ts.ctx, cmd, stopSignal(), ts.gracePeriod)
+               bg.err = waitOrStop(ts.ctx, cmd, quitSignal(), ts.gracePeriod)
                close(done)
        }()
        return bg, nil
 }
 
-// stopSignal returns the appropriate signal to use to request that a process
-// stop execution.
-func stopSignal() os.Signal {
-       if runtime.GOOS == "windows" {
-               // Per https://golang.org/pkg/os/#Signal, “Interrupt is not implemented on
-               // Windows; using it with os.Process.Signal will return an error.”
-               // Fall back to Kill instead.
-               return os.Kill
-       }
-       return os.Interrupt
-}
-
 // waitOrStop waits for the already-started command cmd by calling its Wait method.
 //
 // If cmd does not return before ctx is done, waitOrStop sends it the given interrupt signal.

diff --git a/src/cmd/go/stop_other_test.go b/src/cmd/go/stop_other_test.go
new file mode 100644 (file)
index 0000000..e1cc6cf
--- /dev/null
+++ b/src/cmd/go/stop_other_test.go
@@ -0,0 +1,33 @@
+// Copyright 2021 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.
+
+//go:build !(aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris)
+// +build !aix
+// +build !darwin
+// +build !dragonfly
+// +build !freebsd
+// +build !js !wasm
+// +build !linux
+// +build !netbsd
+// +build !openbsd
+// +build !solaris
+
+package main_test
+
+import (
+       "os"
+       "runtime"
+)
+
+// quitSignal returns the appropriate signal to use to request that a process
+// quit execution.
+func quitSignal() os.Signal {
+       if runtime.GOOS == "windows" {
+               // Per https://golang.org/pkg/os/#Signal, “Interrupt is not implemented on
+               // Windows; using it with os.Process.Signal will return an error.”
+               // Fall back to Kill instead.
+               return os.Kill
+       }
+       return os.Interrupt
+}

diff --git a/src/cmd/go/stop_unix_test.go b/src/cmd/go/stop_unix_test.go
new file mode 100644 (file)
index 0000000..ac35b24
--- /dev/null
+++ b/src/cmd/go/stop_unix_test.go
@@ -0,0 +1,17 @@
+// Copyright 2021 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.
+
+//go:build aix || darwin || dragonfly || freebsd || (js && wasm) || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd js,wasm linux netbsd openbsd solaris
+
+package main_test
+
+import (
+       "os"
+       "syscall"
+)
+
+func quitSignal() os.Signal {
+       return syscall.SIGQUIT
+}