runtime/debug: fix test when source cannot be found

This happens with GOROOT_FINAL=/somewhere/else

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5727069

diff --git a/src/pkg/runtime/debug/stack_test.go b/src/pkg/runtime/debug/stack_test.go
index 94293bb934b512591c5711d26458bf1faab5b72e..f33f5072b40d7797b6f7cb3e9820fd7d18ed6214 100644 (file)
--- a/src/pkg/runtime/debug/stack_test.go
+++ b/src/pkg/runtime/debug/stack_test.go
@@ -39,13 +39,20 @@ func TestStack(t *testing.T) {
        if len(lines) <= 6 {
                t.Fatal("too few lines")
        }
-       check(t, lines[0], "src/pkg/runtime/debug/stack_test.go")
-       check(t, lines[1], "\t(*T).ptrmethod: return Stack()")
-       check(t, lines[2], "src/pkg/runtime/debug/stack_test.go")
-       check(t, lines[3], "\tT.method: return t.ptrmethod()")
-       check(t, lines[4], "src/pkg/runtime/debug/stack_test.go")
-       check(t, lines[5], "\tTestStack: b := T(0).method()")
-       check(t, lines[6], "src/pkg/testing/testing.go")
+       n := 0
+       frame := func(line, code string) {
+               check(t, lines[n], line)
+               n++
+               // The source might not be available while running the test.
+               if strings.HasPrefix(lines[n], "\t") {
+                       check(t, lines[n], code)
+                       n++
+               }
+       }
+       frame("src/pkg/runtime/debug/stack_test.go", "\t(*T).ptrmethod: return Stack()")
+       frame("src/pkg/runtime/debug/stack_test.go", "\tT.method: return t.ptrmethod()")
+       frame("src/pkg/runtime/debug/stack_test.go", "\tTestStack: b := T(0).method()")
+       frame("src/pkg/testing/testing.go", "")
 }
 
 func check(t *testing.T, line, has string) {