testing: remove call to os.Exit in documentation for TestMain

In the example for the TestMain function, os.Exit was called explicitly,
which is no longer necessary since Go 1.15 (see change #219639).

Updates #34129

Change-Id: Ia8021de0d5699742adbb7ab6d28b11c841e596dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/596977
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

diff --git a/src/testing/testing.go b/src/testing/testing.go
index 200fa659b8669733a5ae725b047048c9f884af62..526cba39f8fc92563f425c0cdf92d147563d9322 100644 (file)
--- a/src/testing/testing.go
+++ b/src/testing/testing.go
@@ -362,7 +362,7 @@
 //
 //     func TestMain(m *testing.M) {
 //             // call flag.Parse() here if TestMain uses flags
-//             os.Exit(m.Run())
+//             m.Run()
 //     }
 //
 // TestMain is a low-level primitive and should not be necessary for casual