json.ErrorEmpty

errors.go

@@ -0,0 +1,9 @@
+package opt
+
+import (
+	"github.com/reiver/go-erorr"
+)
+
+const (
+	errBadReflection = erorr.Error("opt: bad reflection")
+)

go.mod

@@ -1,5 +1,10 @@
 module github.com/reiver/go-opt
 
-go 1.18
+go 1.22.4
 
-require github.com/reiver/go-erorr v0.0.0-20240704145350-0485e21eaa82
+require (
+	github.com/reiver/go-erorr v0.0.0-20240801233437-8cbde6d1fa3f
+	github.com/reiver/go-json v0.0.0-20240808163155-5fb56b49f847
+)
+
+require github.com/reiver/go-lck v0.0.0-20240808133902-b56df221c39f // indirect

go.sum

@@ -1,2 +1,6 @@
-github.com/reiver/go-erorr v0.0.0-20240704145350-0485e21eaa82 h1:xxt7qL+7ZfRysXWXU2MpULOg/zWe5P+Fmw9VyUFCmZE=
-github.com/reiver/go-erorr v0.0.0-20240704145350-0485e21eaa82/go.mod h1:F0HbBf+Ak2ZlE8YkDW4Y+KxaUmT0KaaIJK6CXY3cJxE=
+github.com/reiver/go-erorr v0.0.0-20240801233437-8cbde6d1fa3f h1:D1QSxKHm8U73XhjsW3SFLkT0zT5pKJi+1KGboMhY1Rk=
+github.com/reiver/go-erorr v0.0.0-20240801233437-8cbde6d1fa3f/go.mod h1:F0HbBf+Ak2ZlE8YkDW4Y+KxaUmT0KaaIJK6CXY3cJxE=
+github.com/reiver/go-json v0.0.0-20240808163155-5fb56b49f847 h1:Y8BYW4keqqtdEWECdG7Pg60U0awT3DioXiIfcXvWhMY=
+github.com/reiver/go-json v0.0.0-20240808163155-5fb56b49f847/go.mod h1:ns4kpzbK+OyMUZYT8UmBxrsYWNmvB/irZGmyIh99cxY=
+github.com/reiver/go-lck v0.0.0-20240808133902-b56df221c39f h1:KBVWBoNIM8mHkUR3dP64hm2p2vxoD5xHZ6wUllCjFTc=
+github.com/reiver/go-lck v0.0.0-20240808133902-b56df221c39f/go.mod h1:PFseSi8S0CBkc+YB6jYWtogPk83LumclnYJZZBQJJhs=

optional_marshaljson.go

@@ -1,7 +1,11 @@
 package opt
 
 import (
-	"encoding/json"
+	"encoding"
+	"fmt"
+	"reflect"
+
+	"github.com/reiver/go-json"
 
 	"github.com/reiver/go-erorr"
 )
@@ -11,15 +15,22 @@ var _ json.Marshaler = Nothing[string]()
 
 // MarshalJSON makes it so json.Marshaler is implemented.
 func (receiver Optional[T]) MarshalJSON() ([]byte, error) {
+
 	switch interface{}(receiver.value).(type) {
-	case bool, string, json.Marshaler:
+	case json.Marshaler, encoding.TextMarshaler, bool, int, int8, int16, int32, int64, string, uint, uint8, uint16, uint32, uint64:
 		// these are OK.
 	default:
-		return nil, erorr.Errorf("opt: cannot marshal something of type %T into JSON because parameterized type is ‘%T’ rather than ‘bool’, ‘string’, or ‘json.Marshaler’", receiver, receiver.value)
+		var reflectedType reflect.Type = reflect.TypeOf(receiver.value)
+		if nil == reflectedType {
+			return nil, errBadReflection
+		}
+		if reflect.Struct != reflectedType.Kind() {
+			return nil, erorr.Errorf("opt: cannot marshal something of type %T into JSON because parameterized type is ‘%T’ is not supported", receiver, receiver.value)
+		}
 	}
 
 	if receiver.IsNothing() {
-		return nil, erorr.Errorf("opt: cannot marshal opt.Nothing[%T]() into JSON", receiver.value)
+		return nil, json.ErrEmpty(fmt.Sprintf("opt: cannot marshal opt.Nothing[%T]() into JSON", receiver.value))
 	}
 
 	return json.Marshal(receiver.value)

optional_marshaljson_int_test.go

@@ -10,88 +10,118 @@ func TestOptional_MarshalJSON_int(t *testing.T) {
 
 	tests := []struct{
 		Value opt.Optional[int]
+		Expected string
 	}{
 		{
 			Value: opt.Something(-65536),
+			Expected:           `-65536`,
 		},
 		{
 			Value: opt.Something(-65535),
+			Expected:           `-65535`,
 		},
 
 
 
 		{
 			Value: opt.Something(-256),
+			Expected:           `-256`,
 		},
 		{
 			Value: opt.Something(-255),
+			Expected:           `-255`,
 		},
 
 
 
 		{
 			Value: opt.Something(-5),
+			Expected:           `-5`,
 		},
 		{
 			Value: opt.Something(-4),
+			Expected:           `-4`,
 		},
 		{
 			Value: opt.Something(-3),
+			Expected:           `-3`,
 		},
 		{
 			Value: opt.Something(-2),
+			Expected:           `-2`,
 		},
 		{
 			Value: opt.Something(-1),
+			Expected:           `-1`,
 		},
 		{
 			Value: opt.Something(0),
+			Expected:           `0`,
 		},
 		{
 			Value: opt.Something(1),
+			Expected:           `1`,
 		},
 		{
 			Value: opt.Something(2),
+			Expected:           `2`,
 		},
 		{
 			Value: opt.Something(3),
+			Expected:           `3`,
 		},
 		{
 			Value: opt.Something(4),
+			Expected:           `4`,
 		},
 		{
 			Value: opt.Something(5),
+			Expected:           `5`,
 		},
 
 
 
 		{
 			Value: opt.Something(255),
+			Expected:           `255`,
 		},
 		{
 			Value: opt.Something(256),
+			Expected:           `256`,
 		},
 
 
 
 		{
 			Value: opt.Something(65535),
+			Expected:           `65535`,
 		},
 		{
 			Value: opt.Something(65536),
+			Expected:           `65536`,
 		},
 	}
 
 	for testNumber, test := range tests {
 
 		actualBytes, err := test.Value.MarshalJSON()
-		if nil == err {
-			t.Errorf("For test #%d, expected an error but did not actually get one." , testNumber)
-			t.Logf("ACTUAL BYTES: %q", actualBytes)
+		if nil != err {
+			t.Errorf("For test #%d, did not expect an error but actually got one." , testNumber)
 			t.Logf("ERROR: (%T) %s", err, err)
 			t.Logf("VALUE: %#v", test.Value)
 			continue
 		}
+
+		actual := string(actualBytes)
+		expected := test.Expected
+
+		if expected != actual {
+			t.Errorf("For test #%d, the actual value for the JSON marshaling is not what was expected.", testNumber)
+			t.Logf("EXPECTED: %q", expected)
+			t.Logf("ACTUAL:   %q", actual)
+			t.Logf("VALUE: %#v", test.Value)
+			continue
+		}
 	}
 }