1// Copyright (c) 2016 Uber Technologies, Inc.
2//
3// Permission is hereby granted, free of charge, to any person obtaining a copy
4// of this software and associated documentation files (the "Software"), to deal
5// in the Software without restriction, including without limitation the rights
6// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7// copies of the Software, and to permit persons to whom the Software is
8// furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in
11// all copies or substantial portions of the Software.
12//
13// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
19// THE SOFTWARE.
20
21package ztest
22
23import (
24	"bytes"
25	"errors"
26	"io/ioutil"
27	"strings"
28)
29
30// A Syncer is a spy for the Sync portion of zapcore.WriteSyncer.
31type Syncer struct {
32	err    error
33	called bool
34}
35
36// SetError sets the error that the Sync method will return.
37func (s *Syncer) SetError(err error) {
38	s.err = err
39}
40
41// Sync records that it was called, then returns the user-supplied error (if
42// any).
43func (s *Syncer) Sync() error {
44	s.called = true
45	return s.err
46}
47
48// Called reports whether the Sync method was called.
49func (s *Syncer) Called() bool {
50	return s.called
51}
52
53// A Discarder sends all writes to ioutil.Discard.
54type Discarder struct{ Syncer }
55
56// Write implements io.Writer.
57func (d *Discarder) Write(b []byte) (int, error) {
58	return ioutil.Discard.Write(b)
59}
60
61// FailWriter is a WriteSyncer that always returns an error on writes.
62type FailWriter struct{ Syncer }
63
64// Write implements io.Writer.
65func (w FailWriter) Write(b []byte) (int, error) {
66	return len(b), errors.New("failed")
67}
68
69// ShortWriter is a WriteSyncer whose write method never fails, but
70// nevertheless fails to the last byte of the input.
71type ShortWriter struct{ Syncer }
72
73// Write implements io.Writer.
74func (w ShortWriter) Write(b []byte) (int, error) {
75	return len(b) - 1, nil
76}
77
78// Buffer is an implementation of zapcore.WriteSyncer that sends all writes to
79// a bytes.Buffer. It has convenience methods to split the accumulated buffer
80// on newlines.
81type Buffer struct {
82	bytes.Buffer
83	Syncer
84}
85
86// Lines returns the current buffer contents, split on newlines.
87func (b *Buffer) Lines() []string {
88	output := strings.Split(b.String(), "\n")
89	return output[:len(output)-1]
90}
91
92// Stripped returns the current buffer contents with the last trailing newline
93// stripped.
94func (b *Buffer) Stripped() string {
95	return strings.TrimRight(b.String(), "\n")
96}
97