From bd9381b0196de79b30df49f2fbf9da1969da637b Mon Sep 17 00:00:00 2001
From: Fabian Wickborn <fabian@wickborn.net>
Date: Wed, 29 Nov 2017 00:03:24 +0100
Subject: [PATCH] cmd/vfsgendev: Run generator in package directory

Closes #36.
---
 cmd/vfsgendev/generate.go |  4 +++-
 cmd/vfsgendev/main.go     | 21 ++++++++-------------
 2 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/cmd/vfsgendev/generate.go b/cmd/vfsgendev/generate.go
index 046f3f3..f78d425 100644
--- a/cmd/vfsgendev/generate.go
+++ b/cmd/vfsgendev/generate.go
@@ -15,7 +15,9 @@ type data struct {
 
 var generateTemplate = template.Must(template.New("").Funcs(template.FuncMap{
 	"quote": strconv.Quote,
-}).Parse(`package main
+}).Parse(`// +build ignore
+
+package main
 
 import (
 	"log"
diff --git a/cmd/vfsgendev/main.go b/cmd/vfsgendev/main.go
index 0c833e7..52a6a4b 100644
--- a/cmd/vfsgendev/main.go
+++ b/cmd/vfsgendev/main.go
@@ -11,7 +11,7 @@ import (
 	"log"
 	"os"
 	"os/exec"
-	"path/filepath"
+	"strings"
 )
 
 var (
@@ -78,31 +78,26 @@ func run(importPath, variableName, tag string) error {
 		return nil
 	}
 
-	err = goRun(buf.String(), tag)
+	err = goRun(buf.String(), importPath, tag)
 	return err
 }
 
 // goRun runs Go code src with build tags.
-func goRun(src string, tags string) error {
-	// Create a temp folder.
-	tempDir, err := ioutil.TempDir("", "vfsgendev_")
+func goRun(src, importPath, tags string) error {
+	// Create a temp file.
+	importPath = strings.Replace(importPath, "/", "_", -1)
+	tempFile := "vfsgendev_" + importPath + ".go"
+	err := ioutil.WriteFile(tempFile, []byte(src), 0600)
 	if err != nil {
 		return err
 	}
 	defer func() {
-		err := os.RemoveAll(tempDir)
+		err := os.Remove(tempFile)
 		if err != nil {
 			fmt.Fprintln(os.Stderr, "warning: error removing temp dir:", err)
 		}
 	}()
 
-	// Write the source code file.
-	tempFile := filepath.Join(tempDir, "generate.go")
-	err = ioutil.WriteFile(tempFile, []byte(src), 0600)
-	if err != nil {
-		return err
-	}
-
 	// Compile and run the program.
 	cmd := exec.Command("go", "run", "-tags="+tags, tempFile)
 	cmd.Stdout = os.Stdout