From 2615c451cef481904bad24495084d0bfeeb5a3d1 Mon Sep 17 00:00:00 2001
From: David Terei <david.terei@rubrik.com>
Date: Wed, 8 Aug 2018 16:27:25 -0700
Subject: [PATCH] Write to tempfile first then rename

---
 stringer.go | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/stringer.go b/stringer.go
index f32e9e9..5788650 100644
--- a/stringer.go
+++ b/stringer.go
@@ -126,16 +126,31 @@ func main() {
 	// Format the output.
 	src := g.format()
 
-	// Write to file.
+	// Figure out filename to write to
 	outputName := *output
 	if outputName == "" {
 		baseName := fmt.Sprintf("%s_enumer.go", types[0])
 		outputName = filepath.Join(dir, strings.ToLower(baseName))
 	}
-	err := ioutil.WriteFile(outputName, src, 0644)
+
+	// Write to tmpfile first
+	tmpFile, err := ioutil.TempFile("", fmt.Sprintf("%s_enumer_", types[0]))
 	if err != nil {
+		log.Fatalf("creating temporary file for output: %s", err)
+	}
+	_, err = tmpFile.Write(src)
+	if err != nil {
+		tmpFile.Close()
+		os.Remove(tmpFile.Name())
 		log.Fatalf("writing output: %s", err)
 	}
+	tmpFile.Close()
+
+	// Rename tmpfile to output file
+	err = os.Rename(tmpFile.Name(), outputName)
+	if err != nil {
+		log.Fatalf("moving tempfile to output file: %s", err)
+	}
 }
 
 // isDirectory reports whether the named file is a directory.