.

go/internal/xtracing/tracetest/tracetest.go

@@ -263,24 +263,6 @@ func Verify(t *testing.T, f func(t *T)) {
 }
 
 
-// fatalfInNonMain should be called for fatal cases in non-main goroutines instead of panic.
-//
-// we don't panic because it will stop the process and prevent the main
-// goroutine to print detailed reason for e.g. deadlock or other error.
-var fatalLogMu sync.Mutex
-func (t *T) fatalfInNonMain(format string, argv ...interface{}) {
-	t.Helper()
-
-	// serialize fatal log+traceback printout, so that such printouts from
-	// multiple goroutines do not get intermixed.
-	fatalLogMu.Lock()
-	defer fatalLogMu.Unlock()
-
-	t.Logf(format, argv...)
-	t.Logf("%s\n", debug.Stack())
-	runtime.Goexit()
-}
-
 // T overrides FailNow/Fatal/Fatalf to also cancel all in-progress sends.
 func (t *T) FailNow() {
 	t.Helper()
@@ -512,3 +494,21 @@ func (t *T) expect1(stream string, eventExpect interface{}) *_Msg {
 
 	return msg
 }
+
+// fatalfInNonMain should be called for fatal cases in non-main goroutines instead of panic.
+//
+// we don't panic because it will stop the process and prevent the main
+// goroutine to print detailed reason for e.g. deadlock or other error.
+var fatalLogMu sync.Mutex
+func (t *T) fatalfInNonMain(format string, argv ...interface{}) {
+	t.Helper()
+
+	// serialize fatal log+traceback printout, so that such printouts from
+	// multiple goroutines do not get intermixed.
+	fatalLogMu.Lock()
+	defer fatalLogMu.Unlock()
+
+	t.Logf(format, argv...)
+	t.Logf("%s\n", debug.Stack())
+	runtime.Goexit()
+}