From 9ed0e320599bcd559565207bb6a9b0c49a5b36ee Mon Sep 17 00:00:00 2001
From: Cherry Zhang <cherryyz@google.com>
Date: Sun, 11 Apr 2021 13:26:44 -0400
Subject: [PATCH] test: consider default GOEXPERIMENT when matching build tags

If GOEXPERIMENT environment variable is unset, use the default
value that is baked into the toolchain (instead of no
experiments).

Change-Id: I41f863e6f7439f2d53e3ebd25a7d9cf4a176e32e
Reviewed-on: https://go-review.googlesource.com/c/go/+/309333
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
---
 test/run.go | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/run.go b/test/run.go
index 48115ed18d..feab88338c 100644
--- a/test/run.go
+++ b/test/run.go
@@ -446,6 +446,18 @@ func (ctxt *context) match(name string) bool {
 	}
 
 	exp := os.Getenv("GOEXPERIMENT")
+	if exp == "" {
+		// If GOEXPERIMENT environment variable is unset, get the default value
+		// that is baked into the toolchain.
+		cmd := exec.Command(goTool(), "tool", "compile", "-V")
+		out, err := cmd.CombinedOutput()
+		if err == nil {
+			i := bytes.Index(out, []byte("X:"))
+			if i != -1 {
+				exp = string(out[i+2:])
+			}
+		}
+	}
 	if exp != "" {
 		experiments := strings.Split(exp, ",")
 		for _, e := range experiments {