cmd/go: make go test -json report failures for panicking/exiting tests

'go test -json' should report that a test failed if the test binary
did not exit normally with status 0. This covers panics, non-zero
exits, and abnormal terminations.

These tests don't print a final result when run with -test.v (which is
used by 'go test -json'). The final result should be "PASS" or "FAIL"
on a line by itself. 'go test' prints "FAIL" in this case, but
includes error information.

test2json was changed in CL 192104 to report that a test passed if it
does not report a final status. This caused 'go test -json' to report
that a test passed after a panic or non-zero exit.

With this change, test2json treats "FAIL" with error information the
same as "FAIL" on a line by itself. This is intended to be a minimal
fix for backporting, but it will likely be replaced by a complete
solution for #29062.

Fixes #37555
Updates #29062
Updates #31969

Change-Id: Icb67bcd36bed97e6a8d51f4d14bf71f73c83ac3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/222243
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/cmd/go/internal/test/test.go b/src/cmd/go/internal/test/test.go
index 1c6fb0b97f..dbb899219d 100644
--- a/src/cmd/go/internal/test/test.go
+++ b/src/cmd/go/internal/test/test.go
@@ -1239,6 +1239,14 @@ func (c *runCache) builderRunTest(b *work.Builder, a *work.Action) error {
 		if len(out) == 0 {
 			fmt.Fprintf(cmd.Stdout, "%s\n", err)
 		}
+		// NOTE(golang.org/issue/37555): test2json reports that a test passes
+		// unless "FAIL" is printed at the beginning of a line. The test may not
+		// actually print that if it panics, exits, or terminates abnormally,
+		// so we print it here. We can't always check whether it was printed
+		// because some tests need stdout to be a terminal (golang.org/issue/34791),
+		// not a pipe.
+		// TODO(golang.org/issue/29062): tests that exit with status 0 without
+		// printing a final result should fail.
 		fmt.Fprintf(cmd.Stdout, "FAIL\t%s\t%s\n", a.Package.ImportPath, t)
 	}