1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Package imports implements a Go pretty-printer (like package "go/format")
6// that also adds or removes import statements as necessary.
7package imports // import "golang.org/x/tools/imports"
8
9import (
10	"io/ioutil"
11	"log"
12
13	"golang.org/x/tools/internal/gocommand"
14	intimp "golang.org/x/tools/internal/imports"
15)
16
17// Options specifies options for processing files.
18type Options struct {
19	Fragment  bool // Accept fragment of a source file (no package statement)
20	AllErrors bool // Report all errors (not just the first 10 on different lines)
21
22	Comments  bool // Print comments (true if nil *Options provided)
23	TabIndent bool // Use tabs for indent (true if nil *Options provided)
24	TabWidth  int  // Tab width (8 if nil *Options provided)
25
26	FormatOnly bool // Disable the insertion and deletion of imports
27}
28
29// Debug controls verbose logging.
30var Debug = false
31
32// LocalPrefix is a comma-separated string of import path prefixes, which, if
33// set, instructs Process to sort the import paths with the given prefixes
34// into another group after 3rd-party packages.
35var LocalPrefix string
36
37// Process formats and adjusts imports for the provided file.
38// If opt is nil the defaults are used, and if src is nil the source
39// is read from the filesystem.
40//
41// Note that filename's directory influences which imports can be chosen,
42// so it is important that filename be accurate.
43// To process data ``as if'' it were in filename, pass the data as a non-nil src.
44func Process(filename string, src []byte, opt *Options) ([]byte, error) {
45	var err error
46	if src == nil {
47		src, err = ioutil.ReadFile(filename)
48		if err != nil {
49			return nil, err
50		}
51	}
52	if opt == nil {
53		opt = &Options{Comments: true, TabIndent: true, TabWidth: 8}
54	}
55	intopt := &intimp.Options{
56		Env: &intimp.ProcessEnv{
57			GocmdRunner: &gocommand.Runner{},
58		},
59		LocalPrefix: LocalPrefix,
60		AllErrors:   opt.AllErrors,
61		Comments:    opt.Comments,
62		FormatOnly:  opt.FormatOnly,
63		Fragment:    opt.Fragment,
64		TabIndent:   opt.TabIndent,
65		TabWidth:    opt.TabWidth,
66	}
67	if Debug {
68		intopt.Env.Logf = log.Printf
69	}
70	return intimp.Process(filename, src, intopt)
71}
72
73// VendorlessPath returns the devendorized version of the import path ipath.
74// For example, VendorlessPath("foo/bar/vendor/a/b") returns "a/b".
75func VendorlessPath(ipath string) string {
76	return intimp.VendorlessPath(ipath)
77}
78