From be48115f48b4a8e827502771599ee274aaba3117 Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <bradfitz@golang.org>
Date: Tue, 7 Jun 2011 11:53:47 -0700
Subject: [PATCH] gofix: fix diff regression from exec change

Also pass -u to diff to be consistent with gofmt.

Fixes #1619

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/4591041
---
 src/cmd/gofix/main.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/cmd/gofix/main.go b/src/cmd/gofix/main.go
index ba2061a000..1b091c18aa 100644
--- a/src/cmd/gofix/main.go
+++ b/src/cmd/gofix/main.go
@@ -248,5 +248,11 @@ func diff(b1, b2 []byte) (data []byte, err os.Error) {
 	f1.Write(b1)
 	f2.Write(b2)
 
-	return exec.Command("diff", f1.Name(), f2.Name()).CombinedOutput()
+	data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
+	if len(data) > 0 {
+		// diff exits with a non-zero status when the files don't match.
+		// Ignore that failure as long as we get output.
+		err = nil
+	}
+	return
 }
-- 
2.51.0