| // Copyright (c) 2017 Uber Technologies, Inc. |
| // |
| // Permission is hereby granted, free of charge, to any person obtaining a copy |
| // of this software and associated documentation files (the "Software"), to deal |
| // in the Software without restriction, including without limitation the rights |
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| // copies of the Software, and to permit persons to whom the Software is |
| // furnished to do so, subject to the following conditions: |
| // |
| // The above copyright notice and this permission notice shall be included in |
| // all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| // THE SOFTWARE. |
| |
| package multierr |
| |
| import ( |
| "errors" |
| "fmt" |
| "io" |
| "sync" |
| "testing" |
| |
| "github.com/stretchr/testify/assert" |
| "github.com/stretchr/testify/require" |
| ) |
| |
| // richFormatError is an error that prints a different output depending on |
| // whether %v or %+v was used. |
| type richFormatError struct{} |
| |
| func (r richFormatError) Error() string { |
| return fmt.Sprint(r) |
| } |
| |
| func (richFormatError) Format(f fmt.State, c rune) { |
| if c == 'v' && f.Flag('+') { |
| io.WriteString(f, "multiline\nmessage\nwith plus") |
| } else { |
| io.WriteString(f, "without plus") |
| } |
| } |
| |
| func appendN(initial, err error, n int) error { |
| errs := initial |
| for i := 0; i < n; i++ { |
| errs = Append(errs, err) |
| } |
| return errs |
| } |
| |
| func newMultiErr(errors ...error) error { |
| return &multiError{errors: errors} |
| } |
| |
| func TestCombine(t *testing.T) { |
| tests := []struct { |
| // Input |
| giveErrors []error |
| |
| // Resulting error |
| wantError error |
| |
| // %+v and %v string representations |
| wantMultiline string |
| wantSingleline string |
| }{ |
| { |
| giveErrors: nil, |
| wantError: nil, |
| }, |
| { |
| giveErrors: []error{}, |
| wantError: nil, |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| nil, |
| newMultiErr( |
| errors.New("bar"), |
| ), |
| nil, |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar", |
| wantSingleline: "foo; bar", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| newMultiErr( |
| errors.New("bar"), |
| ), |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar", |
| wantSingleline: "foo; bar", |
| }, |
| { |
| giveErrors: []error{errors.New("great sadness")}, |
| wantError: errors.New("great sadness"), |
| wantMultiline: "great sadness", |
| wantSingleline: "great sadness", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| errors.New("bar"), |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar", |
| wantSingleline: "foo; bar", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("great sadness"), |
| errors.New("multi\n line\nerror message"), |
| errors.New("single line error message"), |
| }, |
| wantError: newMultiErr( |
| errors.New("great sadness"), |
| errors.New("multi\n line\nerror message"), |
| errors.New("single line error message"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - great sadness\n" + |
| " - multi\n" + |
| " line\n" + |
| " error message\n" + |
| " - single line error message", |
| wantSingleline: "great sadness; " + |
| "multi\n line\nerror message; " + |
| "single line error message", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| newMultiErr( |
| errors.New("bar"), |
| errors.New("baz"), |
| ), |
| errors.New("qux"), |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| errors.New("baz"), |
| errors.New("qux"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar\n" + |
| " - baz\n" + |
| " - qux", |
| wantSingleline: "foo; bar; baz; qux", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| nil, |
| newMultiErr( |
| errors.New("bar"), |
| ), |
| nil, |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar", |
| wantSingleline: "foo; bar", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| newMultiErr( |
| errors.New("bar"), |
| ), |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - bar", |
| wantSingleline: "foo; bar", |
| }, |
| { |
| giveErrors: []error{ |
| errors.New("foo"), |
| richFormatError{}, |
| errors.New("bar"), |
| }, |
| wantError: newMultiErr( |
| errors.New("foo"), |
| richFormatError{}, |
| errors.New("bar"), |
| ), |
| wantMultiline: "the following errors occurred:\n" + |
| " - foo\n" + |
| " - multiline\n" + |
| " message\n" + |
| " with plus\n" + |
| " - bar", |
| wantSingleline: "foo; without plus; bar", |
| }, |
| } |
| |
| for i, tt := range tests { |
| t.Run(fmt.Sprint(i), func(t *testing.T) { |
| err := Combine(tt.giveErrors...) |
| require.Equal(t, tt.wantError, err) |
| |
| if tt.wantMultiline != "" { |
| t.Run("Sprintf/multiline", func(t *testing.T) { |
| assert.Equal(t, tt.wantMultiline, fmt.Sprintf("%+v", err)) |
| }) |
| } |
| |
| if tt.wantSingleline != "" { |
| t.Run("Sprintf/singleline", func(t *testing.T) { |
| assert.Equal(t, tt.wantSingleline, fmt.Sprintf("%v", err)) |
| }) |
| |
| t.Run("Error()", func(t *testing.T) { |
| assert.Equal(t, tt.wantSingleline, err.Error()) |
| }) |
| |
| if s, ok := err.(fmt.Stringer); ok { |
| t.Run("String()", func(t *testing.T) { |
| assert.Equal(t, tt.wantSingleline, s.String()) |
| }) |
| } |
| } |
| }) |
| } |
| } |
| |
| func TestCombineDoesNotModifySlice(t *testing.T) { |
| errors := []error{ |
| errors.New("foo"), |
| nil, |
| errors.New("bar"), |
| } |
| |
| assert.NotNil(t, Combine(errors...)) |
| assert.Len(t, errors, 3) |
| assert.Nil(t, errors[1], 3) |
| } |
| |
| func TestAppend(t *testing.T) { |
| tests := []struct { |
| left error |
| right error |
| want error |
| }{ |
| { |
| left: nil, |
| right: nil, |
| want: nil, |
| }, |
| { |
| left: nil, |
| right: errors.New("great sadness"), |
| want: errors.New("great sadness"), |
| }, |
| { |
| left: errors.New("great sadness"), |
| right: nil, |
| want: errors.New("great sadness"), |
| }, |
| { |
| left: errors.New("foo"), |
| right: errors.New("bar"), |
| want: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| }, |
| { |
| left: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| right: errors.New("baz"), |
| want: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| errors.New("baz"), |
| ), |
| }, |
| { |
| left: errors.New("baz"), |
| right: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| want: newMultiErr( |
| errors.New("baz"), |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| }, |
| { |
| left: newMultiErr( |
| errors.New("foo"), |
| ), |
| right: newMultiErr( |
| errors.New("bar"), |
| ), |
| want: newMultiErr( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| }, |
| } |
| |
| for _, tt := range tests { |
| assert.Equal(t, tt.want, Append(tt.left, tt.right)) |
| } |
| } |
| |
| type notMultiErr struct{} |
| |
| var _ errorGroup = notMultiErr{} |
| |
| func (notMultiErr) Error() string { |
| return "great sadness" |
| } |
| |
| func (notMultiErr) Errors() []error { |
| return []error{errors.New("great sadness")} |
| } |
| |
| func TestErrors(t *testing.T) { |
| tests := []struct { |
| give error |
| want []error |
| |
| // Don't attempt to cast to errorGroup or *multiError |
| dontCast bool |
| }{ |
| {dontCast: true}, // nil |
| { |
| give: errors.New("hi"), |
| want: []error{errors.New("hi")}, |
| dontCast: true, |
| }, |
| { |
| // We don't yet support non-multierr errors. |
| give: notMultiErr{}, |
| want: []error{notMultiErr{}}, |
| dontCast: true, |
| }, |
| { |
| give: Combine( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| want: []error{ |
| errors.New("foo"), |
| errors.New("bar"), |
| }, |
| }, |
| { |
| give: Append( |
| errors.New("foo"), |
| errors.New("bar"), |
| ), |
| want: []error{ |
| errors.New("foo"), |
| errors.New("bar"), |
| }, |
| }, |
| { |
| give: Append( |
| errors.New("foo"), |
| Combine( |
| errors.New("bar"), |
| ), |
| ), |
| want: []error{ |
| errors.New("foo"), |
| errors.New("bar"), |
| }, |
| }, |
| { |
| give: Combine( |
| errors.New("foo"), |
| Append( |
| errors.New("bar"), |
| errors.New("baz"), |
| ), |
| errors.New("qux"), |
| ), |
| want: []error{ |
| errors.New("foo"), |
| errors.New("bar"), |
| errors.New("baz"), |
| errors.New("qux"), |
| }, |
| }, |
| } |
| |
| for i, tt := range tests { |
| t.Run(fmt.Sprint(i), func(t *testing.T) { |
| t.Run("Errors()", func(t *testing.T) { |
| require.Equal(t, tt.want, Errors(tt.give)) |
| }) |
| |
| if tt.dontCast { |
| return |
| } |
| |
| t.Run("multiError", func(t *testing.T) { |
| require.Equal(t, tt.want, tt.give.(*multiError).Errors()) |
| }) |
| |
| t.Run("errorGroup", func(t *testing.T) { |
| require.Equal(t, tt.want, tt.give.(errorGroup).Errors()) |
| }) |
| }) |
| } |
| } |
| |
| func createMultiErrWithCapacity() error { |
| // Create a multiError that has capacity for more errors so Append will |
| // modify the underlying array that may be shared. |
| return appendN(nil, errors.New("append"), 50) |
| } |
| |
| func TestAppendDoesNotModify(t *testing.T) { |
| initial := createMultiErrWithCapacity() |
| err1 := Append(initial, errors.New("err1")) |
| err2 := Append(initial, errors.New("err2")) |
| |
| // Make sure the error messages match, since we do modify the copyNeeded |
| // atomic, the values cannot be compared. |
| assert.EqualError(t, initial, createMultiErrWithCapacity().Error(), "Initial should not be modified") |
| |
| assert.EqualError(t, err1, Append(createMultiErrWithCapacity(), errors.New("err1")).Error()) |
| assert.EqualError(t, err2, Append(createMultiErrWithCapacity(), errors.New("err2")).Error()) |
| } |
| |
| func TestAppendRace(t *testing.T) { |
| initial := createMultiErrWithCapacity() |
| |
| var wg sync.WaitGroup |
| for i := 0; i < 10; i++ { |
| wg.Add(1) |
| go func() { |
| defer wg.Done() |
| |
| err := initial |
| for j := 0; j < 10; j++ { |
| err = Append(err, errors.New("err")) |
| } |
| }() |
| } |
| |
| wg.Wait() |
| } |
| |
| func TestErrorsSliceIsImmutable(t *testing.T) { |
| err1 := errors.New("err1") |
| err2 := errors.New("err2") |
| |
| err := Append(err1, err2) |
| gotErrors := Errors(err) |
| require.Equal(t, []error{err1, err2}, gotErrors, "errors must match") |
| |
| gotErrors[0] = nil |
| gotErrors[1] = errors.New("err3") |
| |
| require.Equal(t, []error{err1, err2}, Errors(err), |
| "errors must match after modification") |
| } |
| |
| func TestNilMultierror(t *testing.T) { |
| // For safety, all operations on multiError should be safe even if it is |
| // nil. |
| var err *multiError |
| |
| require.Empty(t, err.Error()) |
| require.Empty(t, err.Errors()) |
| } |