Revert "encoding/json: implement Is on all errors"
This reverts CL 254537.
Reason for revert: Reason for revert: The recommended way to check for a type of error is errors.As. API changes should also start with a proposal.
Change-Id: I07c37428575e99c80b17525833a61831d10963bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/254857
Trust: Damien Neil <dneil@google.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
diff --git a/src/encoding/json/decode.go b/src/encoding/json/decode.go
index 1b006ff..86d8a69 100644
--- a/src/encoding/json/decode.go
+++ b/src/encoding/json/decode.go
@@ -136,12 +136,6 @@
return "json: cannot unmarshal " + e.Value + " into Go value of type " + e.Type.String()
}
-// Is returns true if target is a UnmarshalTypeError.
-func (e *UnmarshalTypeError) Is(target error) bool {
- _, ok := target.(*UnmarshalTypeError)
- return ok
-}
-
// An UnmarshalFieldError describes a JSON object key that
// led to an unexported (and therefore unwritable) struct field.
//
@@ -156,24 +150,12 @@
return "json: cannot unmarshal object key " + strconv.Quote(e.Key) + " into unexported field " + e.Field.Name + " of type " + e.Type.String()
}
-// Is returns true if target is a UnmarshalFieldError.
-func (e *UnmarshalFieldError) Is(target error) bool {
- _, ok := target.(*UnmarshalFieldError)
- return ok
-}
-
// An InvalidUnmarshalError describes an invalid argument passed to Unmarshal.
// (The argument to Unmarshal must be a non-nil pointer.)
type InvalidUnmarshalError struct {
Type reflect.Type
}
-// Is returns true if target is a InvalidUnmarshalError.
-func (e *InvalidUnmarshalError) Is(target error) bool {
- _, ok := target.(*InvalidUnmarshalError)
- return ok
-}
-
func (e *InvalidUnmarshalError) Error() string {
if e.Type == nil {
return "json: Unmarshal(nil)"
diff --git a/src/encoding/json/decode_test.go b/src/encoding/json/decode_test.go
index b707dcfa..219e845 100644
--- a/src/encoding/json/decode_test.go
+++ b/src/encoding/json/decode_test.go
@@ -2572,34 +2572,3 @@
}
}
}
-
-func TestInvalidUnmarshalErrorIs(t *testing.T) {
- err := fmt.Errorf("apackage: %w: failed to parse struct", &InvalidUnmarshalError{reflect.TypeOf("a")})
- if !errors.Is(err, &InvalidUnmarshalError{}) {
- t.Fatalf("%v should be unwrapped to a InvalidUnmarshalError", err)
- }
-}
-
-func TestUnmarshalFieldErrorIs(t *testing.T) {
- err := fmt.Errorf("apackage: %w: failed to parse struct", &UnmarshalFieldError{
- Key: "foo",
- Type: reflect.TypeOf("a"),
- Field: reflect.StructField{Name: "b"},
- })
- if !errors.Is(err, &UnmarshalFieldError{}) {
- t.Fatalf("%v should be unwrapped to a UnmarshalFieldError", err)
- }
-}
-
-func TestUnmarshalTypeErrorIs(t *testing.T) {
- err := fmt.Errorf("apackage: %w: failed to parse struct", &UnmarshalTypeError{
- Value: "foo",
- Type: reflect.TypeOf("a"),
- Offset: 1,
- Struct: "Foo",
- Field: "Bar",
- })
- if !errors.Is(err, &UnmarshalTypeError{}) {
- t.Fatalf("%v should be unwrapped to a UnmarshalTypeError", err)
- }
-}
diff --git a/src/encoding/json/encode.go b/src/encoding/json/encode.go
index 8e6b342..578d551 100644
--- a/src/encoding/json/encode.go
+++ b/src/encoding/json/encode.go
@@ -245,12 +245,6 @@
return "json: unsupported value: " + e.Str
}
-// Is returns true if target is a UnsupportedValueError.
-func (e *UnsupportedValueError) Is(target error) bool {
- _, ok := target.(*UnsupportedValueError)
- return ok
-}
-
// Before Go 1.2, an InvalidUTF8Error was returned by Marshal when
// attempting to encode a string value with invalid UTF-8 sequences.
// As of Go 1.2, Marshal instead coerces the string to valid UTF-8 by
@@ -285,12 +279,6 @@
// Unwrap returns the underlying error.
func (e *MarshalerError) Unwrap() error { return e.Err }
-// Is returns true if target is a MarshalerError.
-func (e *MarshalerError) Is(target error) bool {
- _, ok := target.(*MarshalerError)
- return ok
-}
-
var hex = "0123456789abcdef"
// An encodeState encodes JSON into a bytes.Buffer.
diff --git a/src/encoding/json/encode_test.go b/src/encoding/json/encode_test.go
index 90826a7..7290eca 100644
--- a/src/encoding/json/encode_test.go
+++ b/src/encoding/json/encode_test.go
@@ -7,7 +7,6 @@
import (
"bytes"
"encoding"
- "errors"
"fmt"
"log"
"math"
@@ -212,7 +211,7 @@
func TestUnsupportedValues(t *testing.T) {
for _, v := range unsupportedValues {
if _, err := Marshal(v); err != nil {
- if !errors.Is(err, &UnsupportedValueError{}) {
+ if _, ok := err.(*UnsupportedValueError); !ok {
t.Errorf("for %v, got %T want UnsupportedValueError", v, err)
}
} else {
@@ -1156,24 +1155,3 @@
}
}
}
-
-func TestMarshalerErrorIs(t *testing.T) {
- err := fmt.Errorf("apackage: %w: failed to parse struct", &MarshalerError{
- reflect.TypeOf("a"),
- fmt.Errorf("something"),
- "TestMarshalerErrorIs",
- })
- if !errors.Is(err, &MarshalerError{}) {
- t.Fatalf("%v should be unwrapped to a MarshalerError", err)
- }
-}
-
-func TestUnsupportedValueErrorIs(t *testing.T) {
- err := fmt.Errorf("apackage: %w: failed to parse struct", &UnsupportedValueError{
- Value: reflect.Value{},
- Str: "Foo",
- })
- if !errors.Is(err, &UnsupportedValueError{}) {
- t.Fatalf("%v should be unwrapped to a UnsupportedValueError", err)
- }
-}
