From e2457fd27f6239af82c2c132fbc1c58b73bbe362 Mon Sep 17 00:00:00 2001
From: Ross Light <ross@zombiezen.com>
Date: Fri, 28 Jul 2023 12:59:42 -0700
Subject: [PATCH] git: return 0 from exitCode if err == nil

---
 exit.go      | 8 ++++++--
 exit_test.go | 4 ++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/exit.go b/exit.go
index 693fbb2..1ebf400 100644
--- a/exit.go
+++ b/exit.go
@@ -16,9 +16,13 @@ package git
 
 import "errors"
 
-// exitCode returns the exit code indicated by the error, or -1 if the error
-// doesn't indicate an exited process.
+// exitCode returns the exit code indicated by the error,
+// zero if the error is nil,
+// or -1 if the error doesn't indicate an exited process.
 func exitCode(err error) int {
+	if err == nil {
+		return 0
+	}
 	var coder interface {
 		ExitCode() int
 	}
diff --git a/exit_test.go b/exit_test.go
index 5cc1004..a0a5bd8 100644
--- a/exit_test.go
+++ b/exit_test.go
@@ -44,6 +44,10 @@ func TestExitCode(t *testing.T) {
 			err:  errors.New("bork"),
 			want: -1,
 		},
+		{
+			err:  nil,
+			want: 0,
+		},
 	}
 	for _, test := range tests {
 		if got := exitCode(test.err); got != test.want {