runtime: fix TestLldbPython in module mode (again)

When run with GOPATH=/dev/null, go build fails:

$ GOPATH=/dev/null go test -run=TestLldbPython -v -count=1 runtime
=== RUN   TestLldbPython
--- FAIL: TestLldbPython (0.21s)
    runtime-lldb_test.go:169: building source exit status 1
        go: failed to create cache directory /dev/null/pkg/mod/cache: mkdir /dev/null: not a directory
FAIL
FAIL	runtime	0.220s

But run.bash sets GOPATH=/dev/null.

Fix this by setting GOPATH to the empty string before passing to 'go build'.

Fixes #31100

Change-Id: I573c4755d209e0c3eb26c20d4f7870c2961f2782
Reviewed-on: https://go-review.googlesource.com/c/go/+/169918
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

diff --git a/src/runtime/runtime-lldb_test.go b/src/runtime/runtime-lldb_test.go
index c7b769ce83b56257d5ef73d6339c8a49d4bf3daa..985745d97c62be1d6949f6c34533bc91e2f04c9d 100644 (file)
--- a/src/runtime/runtime-lldb_test.go
+++ b/src/runtime/runtime-lldb_test.go
@@ -164,6 +164,7 @@ func TestLldbPython(t *testing.T) {
        // disable it for this test.
        cmd := exec.Command(testenv.GoToolPath(t), "build", "-gcflags=all=-N -l", "-ldflags=-compressdwarf=false", "-o", "a.exe")
        cmd.Dir = dir
+       cmd.Env = append(os.Environ(), "GOPATH=") // issue 31100
        out, err := cmd.CombinedOutput()
        if err != nil {
                t.Fatalf("building source %v\n%s", err, out)