blob: e7e7013c568b6eefe5f17ddba806a10529fe394a [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 (
"bytes"
"exec"
"flag"
"fmt"
"go/parser"
"go/printer"
"go/scanner"
"go/token"
"io/ioutil"
"os"
"path/filepath"
"sort"
"strings"
)
var (
fset = token.NewFileSet()
exitCode = 0
)
var allowedRewrites = flag.String("r", "",
"restrict the rewrites to this comma-separated list")
var allowed map[string]bool
var doDiff = flag.Bool("diff", false, "display diffs instead of rewriting files")
func usage() {
fmt.Fprintf(os.Stderr, "usage: gofix [-diff] [-r fixname,...] [path ...]\n")
flag.PrintDefaults()
fmt.Fprintf(os.Stderr, "\nAvailable rewrites are:\n")
for _, f := range fixes {
fmt.Fprintf(os.Stderr, "\n%s\n", f.name)
desc := strings.TrimSpace(f.desc)
desc = strings.Replace(desc, "\n", "\n\t", -1)
fmt.Fprintf(os.Stderr, "\t%s\n", desc)
}
os.Exit(2)
}
func main() {
sort.Sort(fixes)
flag.Usage = usage
flag.Parse()
if *allowedRewrites != "" {
allowed = make(map[string]bool)
for _, f := range strings.Split(*allowedRewrites, ",") {
allowed[f] = true
}
}
if flag.NArg() == 0 {
if err := processFile("standard input", true); err != nil {
report(err)
}
os.Exit(exitCode)
}
for i := 0; i < flag.NArg(); i++ {
path := flag.Arg(i)
switch dir, err := os.Stat(path); {
case err != nil:
report(err)
case dir.IsRegular():
if err := processFile(path, false); err != nil {
report(err)
}
case dir.IsDirectory():
walkDir(path)
}
}
os.Exit(exitCode)
}
const (
tabWidth = 8
parserMode = parser.ParseComments
printerMode = printer.TabIndent | printer.UseSpaces
)
var printConfig = &printer.Config{
printerMode,
tabWidth,
}
func processFile(filename string, useStdin bool) os.Error {
var f *os.File
var err os.Error
var fixlog bytes.Buffer
var buf bytes.Buffer
if useStdin {
f = os.Stdin
} else {
f, err = os.Open(filename)
if err != nil {
return err
}
defer f.Close()
}
src, err := ioutil.ReadAll(f)
if err != nil {
return err
}
file, err := parser.ParseFile(fset, filename, src, parserMode)
if err != nil {
return err
}
// Apply all fixes to file.
newFile := file
fixed := false
for _, fix := range fixes {
if allowed != nil && !allowed[fix.name] {
continue
}
if fix.f(newFile) {
fixed = true
fmt.Fprintf(&fixlog, " %s", fix.name)
// AST changed.
// Print and parse, to update any missing scoping
// or position information for subsequent fixers.
buf.Reset()
_, err = printConfig.Fprint(&buf, fset, newFile)
if err != nil {
return err
}
newSrc := buf.Bytes()
newFile, err = parser.ParseFile(fset, filename, newSrc, parserMode)
if err != nil {
return err
}
}
}
if !fixed {
return nil
}
fmt.Fprintf(os.Stderr, "%s: fixed %s\n", filename, fixlog.String()[1:])
// Print AST. We did that after each fix, so this appears
// redundant, but it is necessary to generate gofmt-compatible
// source code in a few cases. The official gofmt style is the
// output of the printer run on a standard AST generated by the parser,
// but the source we generated inside the loop above is the
// output of the printer run on a mangled AST generated by a fixer.
buf.Reset()
_, err = printConfig.Fprint(&buf, fset, newFile)
if err != nil {
return err
}
newSrc := buf.Bytes()
if *doDiff {
data, err := diff(src, newSrc)
if err != nil {
return fmt.Errorf("computing diff: %s", err)
}
fmt.Printf("diff %s fixed/%s\n", filename, filename)
os.Stdout.Write(data)
return nil
}
if useStdin {
os.Stdout.Write(newSrc)
return nil
}
return ioutil.WriteFile(f.Name(), newSrc, 0)
}
var gofmtBuf bytes.Buffer
func gofmt(n interface{}) string {
gofmtBuf.Reset()
_, err := printConfig.Fprint(&gofmtBuf, fset, n)
if err != nil {
return "<" + err.String() + ">"
}
return gofmtBuf.String()
}
func report(err os.Error) {
scanner.PrintError(os.Stderr, err)
exitCode = 2
}
func walkDir(path string) {
v := make(fileVisitor)
go func() {
filepath.Walk(path, v, v)
close(v)
}()
for err := range v {
if err != nil {
report(err)
}
}
}
type fileVisitor chan os.Error
func (v fileVisitor) VisitDir(path string, f *os.FileInfo) bool {
return true
}
func (v fileVisitor) VisitFile(path string, f *os.FileInfo) {
if isGoFile(f) {
v <- nil // synchronize error handler
if err := processFile(path, false); err != nil {
v <- err
}
}
}
func isGoFile(f *os.FileInfo) bool {
// ignore non-Go files
return f.IsRegular() && !strings.HasPrefix(f.Name, ".") && strings.HasSuffix(f.Name, ".go")
}
func diff(b1, b2 []byte) (data []byte, err os.Error) {
f1, err := ioutil.TempFile("", "gofix")
if err != nil {
return nil, err
}
defer os.Remove(f1.Name())
defer f1.Close()
f2, err := ioutil.TempFile("", "gofix")
if err != nil {
return nil, err
}
defer os.Remove(f2.Name())
defer f2.Close()
f1.Write(b1)
f2.Write(b2)
data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput()
if len(data) > 0 {
// diff exits with a non-zero status when the files don't match.
// Ignore that failure as long as we get output.
err = nil
}
return
}