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// 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 errors_test
import (
"errors"
"fmt"
"os"
"testing"
)
func TestIs(t *testing.T) {
err1 := errors.New("1")
erra := wrapped{"wrap 2", err1}
errb := wrapped{"wrap 3", erra}
err3 := errors.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},
{err1, nil, false},
{err1, err1, true},
{erra, err1, true},
{errb, err1, true},
{err1, err3, false},
{erra, err3, false},
{errb, err3, false},
{poser, err1, true},
{poser, err3, true},
{poser, erra, false},
{poser, errb, 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 := errors.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,
}, {
wrapped{"pittied the fool", errorT{}},
&errT,
true,
}, {
errF,
&errP,
true,
}, {
errorT{},
&errP,
false,
}, {
wrapped{"wrapped", nil},
&errT,
false,
}, {
&poser{"error", nil},
&errT,
true,
}, {
&poser{"path", nil},
&errP,
true,
}, {
&poser{"oh no", nil},
&p,
true,
}, {
errors.New("err"),
&timeout,
false,
}, {
errF,
&timeout,
true,
}, {
wrapped{"path error", 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 := errors.As(tc.err, tc.target)
if match != tc.match {
t.Fatalf("match: got %v; want %v", 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 := errors.New("error")
for _, tc := range testCases {
t.Run(fmt.Sprintf("%T(%v)", tc, tc), func(t *testing.T) {
defer func() {
recover()
}()
if errors.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 := errors.New("1")
erra := wrapped{"wrap 2", err1}
testCases := []struct {
err error
want error
}{
{nil, nil},
{wrapped{"wrapped", nil}, nil},
{err1, nil},
{erra, err1},
{wrapped{"wrap 3", erra}, erra},
}
for _, tc := range testCases {
if got := errors.Unwrap(tc.err); got != tc.want {
t.Errorf("Unwrap(%v) = %v, want %v", tc.err, got, tc.want)
}
}
}
type errorT struct{}
func (errorT) Error() string { return "errorT" }
type wrapped struct {
msg string
err error
}
func (e wrapped) Error() string { return e.msg }
func (e wrapped) Unwrap() error { return e.err }
type errorUncomparable struct {
f []string
}
func (errorUncomparable) Error() string {
return "uncomparable error"
}
func (errorUncomparable) Is(target error) bool {
_, ok := target.(errorUncomparable)
return ok
}
|
