Respect discriminators of object enums in Scala 3 (#1160)

zio · Sep 17, 2024 · e8b1b79 · e8b1b79
1 parent e88fcd9
commit e8b1b79
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Showing 3 changed files with 25 additions and 2 deletions.
diff --git a/zio-json/shared/src/main/scala-3/zio/json/macros.scala b/zio-json/shared/src/main/scala-3/zio/json/macros.scala
@@ -409,7 +409,7 @@ object DeriveJsonDecoder extends Derivation[JsonDecoder] { self =>
 
  def discrim = ctx.annotations.collectFirst { case jsonDiscriminator(n) => n }
 
- if (isEnumeration) {
+ if (isEnumeration && discrim.isEmpty) {
  new JsonDecoder[A] {
  def unsafeDecode(trace: List[JsonError], in: RetractReader): A = {
  val typeName = Lexer.string(trace, in).toString()
@@ -656,7 +656,7 @@ object DeriveJsonEncoder extends Derivation[JsonEncoder] { self =>
  case jsonDiscriminator(n) => n
  }
 
- if (isEnumeration) {
+ if (isEnumeration && discrim.isEmpty) {
  new JsonEncoder[A] {
  def unsafeEncode(a: A, indent: Option[Int], out: Write): Unit = {
  val typeName = ctx.choose(a) { sub =>

diff --git a/zio-json/shared/src/test/scala-3/zio/json/DerivedDecoderSpec.scala b/zio-json/shared/src/test/scala-3/zio/json/DerivedDecoderSpec.scala
@@ -36,6 +36,18 @@ object DerivedDecoderSpec extends ZIOSpecDefault {
 
  assertTrue(result == Right(Foo.Qux))
  },
+ test("Derives for a sum sealed trait Enumeration type with discriminator") {
+ @jsonDiscriminator("$type")
+ sealed trait Foo derives JsonDecoder
+ object Foo:
+ case object Bar extends Foo
+ case object Baz extends Foo
+ case object Qux extends Foo
+
+ val result = """{"$type":"Qux"}""".fromJson[Foo]
+
+ assertTrue(result == Right(Foo.Qux))
+ },
  test("Derives for a sum ADT type") {
  enum Foo derives JsonDecoder:
  case Bar

diff --git a/zio-json/shared/src/test/scala-3/zio/json/DerivedEncoderSpec.scala b/zio-json/shared/src/test/scala-3/zio/json/DerivedEncoderSpec.scala
@@ -24,6 +24,17 @@ object DerivedEncoderSpec extends ZIOSpecDefault {
 
  assertTrue(json == """"Qux"""")
  },
+ test("Derives for a sum enum Enumeration type with discriminator") {
+ @jsonDiscriminator("$type")
+ enum Foo derives JsonEncoder:
+ case Bar
+ case Baz
+ case Qux
+
+ val json = (Foo.Qux: Foo).toJson
+
+ assertTrue(json == """{"$type":"Qux"}""")
+ },
  test("Derives for a sum sealed trait Enumeration type") {
  sealed trait Foo derives JsonEncoder
  object Foo: