Chore: refine errorgen (#821)

.gitignore

@@ -23,3 +23,5 @@ v2ctl
 mockgen
 vprotogen
 !infra/vprotogen/
+errorgen
+!common/errors/errorgen/

common/errors/errorgen/main.go

@@ -2,11 +2,8 @@ package main
 
 import (
 	"fmt"
-	"log"
 	"os"
 	"path/filepath"
-
-	"github.com/v2fly/v2ray-core/v4/common"
 )
 
 func main() {
@@ -20,26 +17,21 @@ func main() {
 		pkg = "core"
 	}
 
-	moduleName, gmnErr := common.GetModuleName(pwd)
-	if gmnErr != nil {
-		fmt.Println("can not get module path", gmnErr)
-		os.Exit(1)
-	}
-
 	file, err := os.OpenFile("errors.generated.go", os.O_WRONLY|os.O_TRUNC|os.O_CREATE, 0644)
 	if err != nil {
-		log.Fatalf("Failed to generate errors.generated.go: %v", err)
+		fmt.Printf("Failed to generate errors.generated.go: %v", err)
 		os.Exit(1)
 	}
 	defer file.Close()
 
-	fmt.Fprintln(file, "package", pkg)
-	fmt.Fprintln(file, "")
-	fmt.Fprintln(file, "import \""+moduleName+"/common/errors\"")
-	fmt.Fprintln(file, "")
-	fmt.Fprintln(file, "type errPathObjHolder struct{}")
-	fmt.Fprintln(file, "")
-	fmt.Fprintln(file, "func newError(values ...interface{}) *errors.Error {")
-	fmt.Fprintln(file, "	return errors.New(values...).WithPathObj(errPathObjHolder{})")
-	fmt.Fprintln(file, "}")
+	fmt.Fprintf(file, `package %s
+
+import "github.com/v2fly/v2ray-core/v4/common/errors"
+
+type errPathObjHolder struct{}
+
+func newError(values ...interface{}) *errors.Error {
+	return errors.New(values...).WithPathObj(errPathObjHolder{})
+}
+`, pkg)
 }