use DecodeError as internal interface for all errors.

Author: m1k1o

errors.go

@@ -5,40 +5,53 @@ import (
 	"reflect"
 )
 
-// ErrCannotDecode is a generic error type that holds information about
+// DecodeError is a generic error type that holds information about
 // a decoding error together with the name of the field that caused the error.
-type ErrCannotDecode struct {
-	Name string
-	Err  error
+type DecodeError struct {
+	name string
+	err  error
 }
 
-func (e *ErrCannotDecode) Error() string {
-	return fmt.Sprintf("'%s': %s", e.Name, e.Err)
+func newDecodeError(name string, err error) *DecodeError {
+	return &DecodeError{
+		name: name,
+		err:  err,
+	}
 }
 
-// ErrCannotParse extends ErrCannotDecode to include additional information
-// about the expected type and the actual value that could not be parsed.
-type ErrCannotParse struct {
-	ErrCannotDecode
+func (e *DecodeError) Name() string {
+	return e.name
+}
+
+func (e *DecodeError) Unwrap() error {
+	return e.err
+}
+
+func (e *DecodeError) Error() string {
+	return fmt.Sprintf("'%s' %s", e.name, e.err)
+}
+
+// ParseError is an error type that indicates a value could not be parsed
+// into the expected type.
+type ParseError struct {
 	Expected reflect.Value
 	Value    interface{}
+	Err      error
 }
 
-func (e *ErrCannotParse) Error() string {
-	return fmt.Sprintf("'%s' cannot parse '%s' as '%s': %s",
-		e.Name, e.Value, e.Expected.Type(), e.Err)
+func (e *ParseError) Error() string {
+	return fmt.Sprintf("cannot parse '%s' as '%s': %s",
+		e.Value, e.Expected.Type(), e.Err)
 }
 
-// ErrUnconvertibleType is an error type that indicates a value could not be
-// converted to the expected type. It includes the name of the field, the
-// expected type, and the actual value that was attempted to be converted.
-type ErrUnconvertibleType struct {
-	Name     string
+// UnconvertibleTypeError is an error type that indicates a value could not be
+// converted to the expected type.
+type UnconvertibleTypeError struct {
 	Expected reflect.Value
 	Value    interface{}
 }
 
-func (e *ErrUnconvertibleType) Error() string {
-	return fmt.Sprintf("'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
-		e.Name, e.Expected.Type(), reflect.TypeOf(e.Value), e.Value)
+func (e *UnconvertibleTypeError) Error() string {
+	return fmt.Sprintf("expected type '%s', got unconvertible type '%s', value: '%v'",
+		e.Expected.Type(), reflect.TypeOf(e.Value), e.Value)
 }