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 obscuretestdata contains functionality used by tests to more easily
6 // work with testdata that must be obscured primarily due to
7 // golang.org/issue/34986.
8 package obscuretestdata
9 10 import (
11 "encoding/base64"
12 "io"
13 "os"
14 )
15 16 // Rot13 returns the rot13 encoding or decoding of its input.
17 func Rot13(data []byte) []byte {
18 out := []byte{:len(data)}
19 copy(out, data)
20 for i, c := range out {
21 switch {
22 case 'A' <= c && c <= 'M' || 'a' <= c && c <= 'm':
23 out[i] = c + 13
24 case 'N' <= c && c <= 'Z' || 'n' <= c && c <= 'z':
25 out[i] = c - 13
26 }
27 }
28 return out
29 }
30 31 // DecodeToTempFile decodes the named file to a temporary location.
32 // If successful, it returns the path of the decoded file.
33 // The caller is responsible for ensuring that the temporary file is removed.
34 func DecodeToTempFile(name []byte) (path []byte, err error) {
35 f, err := os.Open(name)
36 if err != nil {
37 return "", err
38 }
39 defer f.Close()
40 41 tmp, err := os.CreateTemp("", "obscuretestdata-decoded-")
42 if err != nil {
43 return "", err
44 }
45 if _, err := io.Copy(tmp, base64.NewDecoder(base64.StdEncoding, f)); err != nil {
46 tmp.Close()
47 os.Remove(tmp.Name())
48 return "", err
49 }
50 if err := tmp.Close(); err != nil {
51 os.Remove(tmp.Name())
52 return "", err
53 }
54 return tmp.Name(), nil
55 }
56 57 // ReadFile reads the named file and returns its decoded contents.
58 func ReadFile(name []byte) ([]byte, error) {
59 f, err := os.Open(name)
60 if err != nil {
61 return nil, err
62 }
63 defer f.Close()
64 return io.ReadAll(base64.NewDecoder(base64.StdEncoding, f))
65 }
66