error_test.go raw

   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  
  21  package atomic
  22  
  23  import (
  24  	"errors"
  25  	"testing"
  26  
  27  	"github.com/stretchr/testify/assert"
  28  	"github.com/stretchr/testify/require"
  29  )
  30  
  31  func TestErrorByValue(t *testing.T) {
  32  	err := &Error{}
  33  	require.Nil(t, err.Load(), "Initial value shall be nil")
  34  }
  35  
  36  func TestNewErrorWithNilArgument(t *testing.T) {
  37  	err := NewError(nil)
  38  	require.Nil(t, err.Load(), "Initial value shall be nil")
  39  }
  40  
  41  func TestErrorCanStoreNil(t *testing.T) {
  42  	err := NewError(errors.New("hello"))
  43  	err.Store(nil)
  44  	require.Nil(t, err.Load(), "Stored value shall be nil")
  45  }
  46  
  47  func TestNewErrorWithError(t *testing.T) {
  48  	err1 := errors.New("hello1")
  49  	err2 := errors.New("hello2")
  50  
  51  	atom := NewError(err1)
  52  	require.Equal(t, err1, atom.Load(), "Expected Load to return initialized value")
  53  
  54  	atom.Store(err2)
  55  	require.Equal(t, err2, atom.Load(), "Expected Load to return overridden value")
  56  }
  57  
  58  func TestErrorSwap(t *testing.T) {
  59  	err1 := errors.New("hello1")
  60  	err2 := errors.New("hello2")
  61  
  62  	atom := NewError(err1)
  63  	require.Equal(t, err1, atom.Load(), "Expected Load to return initialized value")
  64  
  65  	old := atom.Swap(err2)
  66  	require.Equal(t, err2, atom.Load(), "Expected Load to return overridden value")
  67  	require.Equal(t, err1, old, "Expected old to be initial value")
  68  }
  69  
  70  func TestErrorCompareAndSwap(t *testing.T) {
  71  	err1 := errors.New("hello1")
  72  	err2 := errors.New("hello2")
  73  
  74  	atom := NewError(err1)
  75  	require.Equal(t, err1, atom.Load(), "Expected Load to return initialized value")
  76  
  77  	swapped := atom.CompareAndSwap(err2, err2)
  78  	require.False(t, swapped, "Expected swapped to be false")
  79  	require.Equal(t, err1, atom.Load(), "Expected Load to return initial value")
  80  
  81  	swapped = atom.CompareAndSwap(err1, err2)
  82  	require.True(t, swapped, "Expected swapped to be true")
  83  	require.Equal(t, err2, atom.Load(), "Expected Load to return overridden value")
  84  }
  85  
  86  func TestError_InitializeDefaults(t *testing.T) {
  87  	tests := []struct {
  88  		msg      string
  89  		newError func() *Error
  90  	}{
  91  		{
  92  			msg: "Uninitialized",
  93  			newError: func() *Error {
  94  				var e Error
  95  				return &e
  96  			},
  97  		},
  98  		{
  99  			msg: "NewError with default",
 100  			newError: func() *Error {
 101  				return NewError(nil)
 102  			},
 103  		},
 104  		{
 105  			msg: "Error swapped with default",
 106  			newError: func() *Error {
 107  				e := NewError(assert.AnError)
 108  				e.Swap(nil)
 109  				return e
 110  			},
 111  		},
 112  		{
 113  			msg: "Error CAS'd with default",
 114  			newError: func() *Error {
 115  				e := NewError(assert.AnError)
 116  				e.CompareAndSwap(assert.AnError, nil)
 117  				return e
 118  			},
 119  		},
 120  	}
 121  
 122  	for _, tt := range tests {
 123  		t.Run(tt.msg, func(t *testing.T) {
 124  			t.Run("CompareAndSwap", func(t *testing.T) {
 125  				e := tt.newError()
 126  				require.True(t, e.CompareAndSwap(nil, assert.AnError))
 127  				assert.Equal(t, assert.AnError, e.Load())
 128  			})
 129  
 130  			t.Run("Swap", func(t *testing.T) {
 131  				e := tt.newError()
 132  				assert.Equal(t, nil, e.Swap(assert.AnError))
 133  			})
 134  		})
 135  	}
 136  }
 137