testing: emphasize that Fatal/FailNow/etc run deferred calls

Fixes #22989.

Change-Id: I9776a7b0d0598c2cb118c323d1f8f933665da254
Reviewed-on: https://go-review.googlesource.com/83881
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

diff --git a/src/testing/testing.go b/src/testing/testing.go
index 1c3ed20585b0407cc1009b4fe28d799553e5ba6b..13937b6ad495c4911e3156345af713acef8828a5 100644 (file)
--- a/src/testing/testing.go
+++ b/src/testing/testing.go
@@ -520,7 +520,8 @@ func (c *common) Failed() bool {
 }
 
 // FailNow marks the function as having failed and stops its execution
-// by calling runtime.Goexit.
+// by calling runtime.Goexit (which then runs all deferred calls in the
+// current goroutine).
 // Execution will continue at the next test or benchmark.
 // FailNow must be called from the goroutine running the
 // test or benchmark function, not from other goroutines