blob: 0df6ad749690c1ae573e437828a30949983d031b [file] [log] [blame]
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
import (
func init() {
var hashSumFix = fix{
`Pass a nil argument to calls to hash.Sum
This fix rewrites code so that it passes a nil argument to hash.Sum.
The additional argument will allow callers to avoid an
allocation in the future.
// Type-checking configuration: tell the type-checker this basic
// information about types, functions, and variables in external packages.
var hashSumTypeConfig = &TypeConfig{
Var: map[string]string{
"crypto.MD4": "crypto.Hash",
"crypto.MD5": "crypto.Hash",
"crypto.SHA1": "crypto.Hash",
"crypto.SHA224": "crypto.Hash",
"crypto.SHA256": "crypto.Hash",
"crypto.SHA384": "crypto.Hash",
"crypto.SHA512": "crypto.Hash",
"crypto.MD5SHA1": "crypto.Hash",
"crypto.RIPEMD160": "crypto.Hash",
Func: map[string]string{
"adler32.New": "hash.Hash",
"crc32.New": "hash.Hash",
"crc32.NewIEEE": "hash.Hash",
"crc64.New": "hash.Hash",
"fnv.New32a": "hash.Hash",
"fnv.New32": "hash.Hash",
"fnv.New64a": "hash.Hash",
"fnv.New64": "hash.Hash",
"hmac.New": "hash.Hash",
"hmac.NewMD5": "hash.Hash",
"hmac.NewSHA1": "hash.Hash",
"hmac.NewSHA256": "hash.Hash",
"md4.New": "hash.Hash",
"md5.New": "hash.Hash",
"ripemd160.New": "hash.Hash",
"sha1.New224": "hash.Hash",
"sha1.New": "hash.Hash",
"sha256.New224": "hash.Hash",
"sha256.New": "hash.Hash",
"sha512.New384": "hash.Hash",
"sha512.New": "hash.Hash",
Type: map[string]*Type{
"crypto.Hash": {
Method: map[string]string{
"New": "func() hash.Hash",
func hashSumFn(f *ast.File) bool {
typeof, _ := typecheck(hashSumTypeConfig, f)
fixed := false
walk(f, func(n interface{}) {
call, ok := n.(*ast.CallExpr)
if ok && len(call.Args) == 0 {
sel, ok := call.Fun.(*ast.SelectorExpr)
if ok && sel.Sel.Name == "Sum" && typeof[sel.X] == "hash.Hash" {
call.Args = append(call.Args, ast.NewIdent("nil"))
fixed = true
return fixed