errors_test.go

Documentation: golang.org/x/xerrors

     1  // Copyright 2011 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 xerrors_test
     6  
     7  import (
     8  	"fmt"
     9  	"regexp"
    10  	"testing"
    11  
    12  	"golang.org/x/xerrors"
    13  )
    14  
    15  func TestNewEqual(t *testing.T) {
    16  	// Different allocations should not be equal.
    17  	if xerrors.New("abc") == xerrors.New("abc") {
    18  		t.Errorf(`New("abc") == New("abc")`)
    19  	}
    20  	if xerrors.New("abc") == xerrors.New("xyz") {
    21  		t.Errorf(`New("abc") == New("xyz")`)
    22  	}
    23  
    24  	// Same allocation should be equal to itself (not crash).
    25  	err := xerrors.New("jkl")
    26  	if err != err {
    27  		t.Errorf(`err != err`)
    28  	}
    29  }
    30  
    31  func TestErrorMethod(t *testing.T) {
    32  	err := xerrors.New("abc")
    33  	if err.Error() != "abc" {
    34  		t.Errorf(`New("abc").Error() = %q, want %q`, err.Error(), "abc")
    35  	}
    36  }
    37  
    38  func TestNewDetail(t *testing.T) {
    39  	got := fmt.Sprintf("%+v", xerrors.New("error"))
    40  	want := `(?s)error:.+errors_test.go:\d+`
    41  	ok, err := regexp.MatchString(want, got)
    42  	if err != nil {
    43  		t.Fatal(err)
    44  	}
    45  	if !ok {
    46  		t.Errorf(`fmt.Sprintf("%%+v", New("error")) = %q, want %q"`, got, want)
    47  	}
    48  }
    49  
    50  func ExampleNew() {
    51  	err := xerrors.New("emit macho dwarf: elf header corrupted")
    52  	if err != nil {
    53  		fmt.Print(err)
    54  	}
    55  	// Output: emit macho dwarf: elf header corrupted
    56  }
    57  
    58  // The fmt package's Errorf function lets us use the package's formatting
    59  // features to create descriptive error messages.
    60  func ExampleNew_errorf() {
    61  	const name, id = "bimmler", 17
    62  	err := fmt.Errorf("user %q (id %d) not found", name, id)
    63  	if err != nil {
    64  		fmt.Print(err)
    65  	}
    66  	// Output: user "bimmler" (id 17) not found
    67  }
    68
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