os/exec: make skipStdinCopyError a function instead of a variable

This makes clearer that skipStdinCopyError is always defined and never
overridden in tests.

Secondarily, it may also help reduce init-time work and allow the
linker and/or inliner to better optimize this package.

(Noticed while prototyping #50436.)

Change-Id: I4f3c1bc146384a98136a4039f82165ed106c14b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/401897
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

1 files changed, 11 insertions, 11 deletions

diff --git a/src/os/exec/exec_windows.go b/src/os/exec/exec_windows.go
index bb937f8aed..e7a2ee6c9d 100644
--- a/src/os/exec/exec_windows.go
+++ b/src/os/exec/exec_windows.go
@@ -9,15 +9,15 @@ import (
 	"syscall"
 )
 
-func init() {
-	skipStdinCopyError = func(err error) bool {
-		// Ignore ERROR_BROKEN_PIPE and ERROR_NO_DATA errors copying
-		// to stdin if the program completed successfully otherwise.
-		// See Issue 20445.
-		const _ERROR_NO_DATA = syscall.Errno(0xe8)
-		pe, ok := err.(*fs.PathError)
-		return ok &&
-			pe.Op == "write" && pe.Path == "|1" &&
-			(pe.Err == syscall.ERROR_BROKEN_PIPE || pe.Err == _ERROR_NO_DATA)
-	}
+// skipStdinCopyError optionally specifies a function which reports
+// whether the provided stdin copy error should be ignored.
+func skipStdinCopyError(err error) bool {
+	// Ignore ERROR_BROKEN_PIPE and ERROR_NO_DATA errors copying
+	// to stdin if the program completed successfully otherwise.
+	// See Issue 20445.
+	const _ERROR_NO_DATA = syscall.Errno(0xe8)
+	pe, ok := err.(*fs.PathError)
+	return ok &&
+		pe.Op == "write" && pe.Path == "|1" &&
+		(pe.Err == syscall.ERROR_BROKEN_PIPE || pe.Err == _ERROR_NO_DATA)
 }