aboutsummaryrefslogtreecommitdiffstats
path: root/vendor/golang.org/x/xerrors/wrap_test.go
blob: e9e1675fc2232529aed26e3932a617a22d0bec00 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
// Copyright 2018 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 xerrors_test

import (
	"fmt"
	"os"
	"testing"

	"golang.org/x/xerrors"
)

func TestIs(t *testing.T) {
	err1 := xerrors.New("1")
	erra := xerrors.Errorf("wrap 2: %w", err1)
	errb := xerrors.Errorf("wrap 3: %w", erra)
	erro := xerrors.Opaque(err1)
	errco := xerrors.Errorf("opaque: %w", erro)
	err3 := xerrors.New("3")

	poser := &poser{"either 1 or 3", func(err error) bool {
		return err == err1 || err == err3
	}}

	testCases := []struct {
		err    error
		target error
		match  bool
	}{
		{nil, nil, true},
		{nil, err1, false},
		{err1, nil, false},
		{err1, err1, true},
		{erra, err1, true},
		{errb, err1, true},
		{errco, erro, true},
		{errco, err1, false},
		{erro, erro, true},
		{err1, err3, false},
		{erra, err3, false},
		{errb, err3, false},
		{poser, err1, true},
		{poser, err3, true},
		{poser, erra, false},
		{poser, errb, false},
		{poser, erro, false},
		{poser, errco, false},
		{errorUncomparable{}, errorUncomparable{}, true},
		{errorUncomparable{}, &errorUncomparable{}, false},
		{&errorUncomparable{}, errorUncomparable{}, true},
		{&errorUncomparable{}, &errorUncomparable{}, false},
		{errorUncomparable{}, err1, false},
		{&errorUncomparable{}, err1, false},
	}
	for _, tc := range testCases {
		t.Run("", func(t *testing.T) {
			if got := xerrors.Is(tc.err, tc.target); got != tc.match {
				t.Errorf("Is(%v, %v) = %v, want %v", tc.err, tc.target, got, tc.match)
			}
		})
	}
}

type poser struct {
	msg string
	f   func(error) bool
}

func (p *poser) Error() string     { return p.msg }
func (p *poser) Is(err error) bool { return p.f(err) }
func (p *poser) As(err interface{}) bool {
	switch x := err.(type) {
	case **poser:
		*x = p
	case *errorT:
		*x = errorT{}
	case **os.PathError:
		*x = &os.PathError{}
	default:
		return false
	}
	return true
}

func TestAs(t *testing.T) {
	var errT errorT
	var errP *os.PathError
	var timeout interface{ Timeout() bool }
	var p *poser
	_, errF := os.Open("non-existing")

	testCases := []struct {
		err    error
		target interface{}
		match  bool
	}{{
		nil,
		&errP,
		false,
	}, {
		xerrors.Errorf("pittied the fool: %w", errorT{}),
		&errT,
		true,
	}, {
		errF,
		&errP,
		true,
	}, {
		xerrors.Opaque(errT),
		&errT,
		false,
	}, {
		errorT{},
		&errP,
		false,
	}, {
		errWrap{nil},
		&errT,
		false,
	}, {
		&poser{"error", nil},
		&errT,
		true,
	}, {
		&poser{"path", nil},
		&errP,
		true,
	}, {
		&poser{"oh no", nil},
		&p,
		true,
	}, {
		xerrors.New("err"),
		&timeout,
		false,
	}, {
		errF,
		&timeout,
		true,
	}, {
		xerrors.Errorf("path error: %w", errF),
		&timeout,
		true,
	}}
	for i, tc := range testCases {
		name := fmt.Sprintf("%d:As(Errorf(..., %v), %v)", i, tc.err, tc.target)
		t.Run(name, func(t *testing.T) {
			match := xerrors.As(tc.err, tc.target)
			if match != tc.match {
				t.Fatalf("xerrors.As(%T, %T): got %v; want %v", tc.err, tc.target, match, tc.match)
			}
			if !match {
				return
			}
			if tc.target == nil {
				t.Fatalf("non-nil result after match")
			}
		})
	}
}

func TestAsValidation(t *testing.T) {
	var s string
	testCases := []interface{}{
		nil,
		(*int)(nil),
		"error",
		&s,
	}
	err := xerrors.New("error")
	for _, tc := range testCases {
		t.Run(fmt.Sprintf("%T(%v)", tc, tc), func(t *testing.T) {
			defer func() {
				recover()
			}()
			if xerrors.As(err, tc) {
				t.Errorf("As(err, %T(%v)) = true, want false", tc, tc)
				return
			}
			t.Errorf("As(err, %T(%v)) did not panic", tc, tc)
		})
	}
}

func TestUnwrap(t *testing.T) {
	err1 := xerrors.New("1")
	erra := xerrors.Errorf("wrap 2: %w", err1)
	erro := xerrors.Opaque(err1)

	testCases := []struct {
		err  error
		want error
	}{
		{nil, nil},
		{errWrap{nil}, nil},
		{err1, nil},
		{erra, err1},
		{xerrors.Errorf("wrap 3: %w", erra), erra},

		{erro, nil},
		{xerrors.Errorf("opaque: %w", erro), erro},
	}
	for _, tc := range testCases {
		if got := xerrors.Unwrap(tc.err); got != tc.want {
			t.Errorf("Unwrap(%v) = %v, want %v", tc.err, got, tc.want)
		}
	}
}

func TestOpaque(t *testing.T) {
	got := fmt.Sprintf("%v", xerrors.Errorf("foo: %v", xerrors.Opaque(errorT{})))
	want := "foo: errorT"
	if got != want {
		t.Errorf("error without Format: got %v; want %v", got, want)
	}

	got = fmt.Sprintf("%v", xerrors.Errorf("foo: %v", xerrors.Opaque(errorD{})))
	want = "foo: errorD"
	if got != want {
		t.Errorf("error with Format: got %v; want %v", got, want)
	}
}

type errorT struct{}

func (errorT) Error() string { return "errorT" }

type errorD struct{}

func (errorD) Error() string { return "errorD" }

func (errorD) FormatError(p xerrors.Printer) error {
	p.Print("errorD")
	p.Detail()
	p.Print("detail")
	return nil
}

type errWrap struct{ error }

func (errWrap) Error() string { return "wrapped" }

func (errWrap) Unwrap() error { return nil }

type errorUncomparable struct {
	f []string
}

func (errorUncomparable) Error() string {
	return "uncomparable error"
}

func (errorUncomparable) Is(target error) bool {
	_, ok := target.(errorUncomparable)
	return ok
}