charleskorn · charleskorn · Jan 14, 2024 · Dec 14, 2023 · Jan 9, 2024 · Jan 9, 2024
diff --git a/src/commonMain/kotlin/com/charleskorn/kaml/YamlConfiguration.kt b/src/commonMain/kotlin/com/charleskorn/kaml/YamlConfiguration.kt
@@ -35,7 35,7 @@ package com.charleskorn.kaml
  * * [sequenceBlockIndent]: number of spaces to use as indentation for sequences, if [sequenceStyle] set to [SequenceStyle.Block]
  * * [allowAnchorsAndAliases]: set to true to allow anchors and aliases when decoding YAML (defaults to `false`)
  */
-public data class YamlConfiguration constructor(
 public data class YamlConfiguration(
  internal val encodeDefaults: Boolean = true,
  internal val strictMode: Boolean = true,
  internal val extensionDefinitionPrefix: String? = null,
@@ -55,6 55,7 @@ public data class YamlConfiguration constructor(
 public enum class PolymorphismStyle {
  Tag,
  Property,
  None,
 }
 
 public enum class SequenceStyle {

diff --git a/src/commonMain/kotlin/com/charleskorn/kaml/YamlInput.kt b/src/commonMain/kotlin/com/charleskorn/kaml/YamlInput.kt
@@ -63,14 63,21 @@ public sealed class YamlInput(
  is StructureKind.MAP -> YamlMapInput(node, yaml, context, configuration)
  is SerialKind.CONTEXTUAL -> YamlContextualInput(node, yaml, context, configuration)
  is PolymorphicKind -> when (configuration.polymorphismStyle) {
  PolymorphismStyle.None ->
  throw IncorrectTypeException("Encountered a polymorphic map descriptor but PolymorphismStyle is 'None'", node.path)
  PolymorphismStyle.Tag -> throw MissingTypeTagException(node.path)
  PolymorphismStyle.Property -> createPolymorphicMapDeserializer(node, yaml, context, configuration)
  }
  else -> throw IncorrectTypeException("Expected ${descriptor.kind.friendlyDescription}, but got a map", node.path)
  }
 
  is YamlTaggedNode -> when {
- descriptor.kind is PolymorphicKind && configuration.polymorphismStyle == PolymorphismStyle.Tag -> YamlPolymorphicInput(node.tag, node.path, node.innerNode, yaml, context, configuration)
  descriptor.kind is PolymorphicKind && configuration.polymorphismStyle == PolymorphismStyle.None -> {
  throw IncorrectTypeException("Encountered a tagged polymorphic descriptor but PolymorphismStyle is 'None'", node.path)
  }
  descriptor.kind is PolymorphicKind && configuration.polymorphismStyle == PolymorphismStyle.Tag -> {
  YamlPolymorphicInput(node.tag, node.path, node.innerNode, yaml, context, configuration)
  }
  else -> createFor(node.innerNode, yaml, context, configuration, descriptor)
  }
  }

diff --git a/src/commonTest/kotlin/com/charleskorn/kaml/YamlReadingTest.kt b/src/commonTest/kotlin/com/charleskorn/kaml/YamlReadingTest.kt
@@ -2029,6 2029,49 @@ class YamlReadingTest : DescribeSpec({
  }
  }
  }
 
  describe("given polymorphic inputs when PolymorphismStyle.None is used") {
  val polymorphicYaml = Yaml(serializersModule = polymorphicModule, configuration = YamlConfiguration(polymorphismStyle = PolymorphismStyle.None))
 
  context("given tagged input") {
  val input = """
  !<sealedString>
  value: "asdfg"
  """.trimIndent()
 
  context("parsing that input") {
  it("throws an appropriate exception") {
  val exception = shouldThrow<IncorrectTypeException> { polymorphicYaml.decodeFromString(TestSealedStructure.serializer(), input) }
 
  exception.asClue {
  it.message shouldBe "Encountered a tagged polymorphic descriptor but PolymorphismStyle is 'None'"
  it.line shouldBe 1
  it.column shouldBe 1
  it.path shouldBe YamlPath.root
  }
  }
  }
  }
  context("given property polymorphism input") {
  val input = """
  type: sealedString
  value: "asdfg"
  """.trimIndent()
 
  context("parsing that input") {
  it("throws an appropriate exception") {
  val exception = shouldThrow<IncorrectTypeException> { polymorphicYaml.decodeFromString(TestSealedStructure.serializer(), input) }
 
  exception.asClue {
  it.message shouldBe "Encountered a polymorphic map descriptor but PolymorphismStyle is 'None'"
  it.line shouldBe 1
  it.column shouldBe 1
  it.path shouldBe YamlPath.root
  }
  }
  }
  }
  }
  }
 
  describe("parsing values with a dynamically installed serializer") {

diff --git a/src/jsMain/kotlin/com/charleskorn/kaml/YamlOutput.kt b/src/jsMain/kotlin/com/charleskorn/kaml/YamlOutput.kt
@@ -130,6 130,9 @@ internal class YamlOutput(
  emitQuotedScalar(typeName, SingleLineStringStyle.DoubleQuoted.scalarStyle)
  }
  }
  PolymorphismStyle.None -> {
  emitter.emit(MappingStartEvent(null, null, true, FlowStyle.BLOCK))
  }
  }
  }
  else -> {

diff --git a/src/jvmMain/kotlin/com/charleskorn/kaml/YamlOutput.kt b/src/jvmMain/kotlin/com/charleskorn/kaml/YamlOutput.kt
@@ -131,6 131,9 @@ internal class YamlOutput(
  emitQuotedScalar(typeName.get(), SingleLineStringStyle.DoubleQuoted.scalarStyle)
  }
  }
  PolymorphismStyle.None -> {
  emitter.emit(MappingStartEvent(Optional.empty(), Optional.empty(), true, FlowStyle.BLOCK))
  }
  }
  }
  else -> {

diff --git a/src/jvmTest/kotlin/com/charleskorn/kaml/JvmYamlWritingTest.kt b/src/jvmTest/kotlin/com/charleskorn/kaml/JvmYamlWritingTest.kt
@@ -20,6 20,7 @@ package com.charleskorn.kaml
 
 import io.kotest.core.spec.style.DescribeSpec
 import io.kotest.matchers.shouldBe
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.builtins.serializer
 import java.io.ByteArrayOutputStream
 
@@ -103,6 104,68 @@ class JvmYamlWritingTest : DescribeSpec({
  """.trimMargin()
  }
  }
 
  it("should support polymorphic writing with property") {
  with(
  Yaml(
  configuration = YamlConfiguration(
  polymorphismStyle = PolymorphismStyle.Property,
  ),
  ),
  ) {
  val output = ByteArrayOutputStream()
  encodeToStream(Animals.serializer(), Animals(listOf(Animal.Dog("Spock"))), output)
 
  output.toString(Charsets.UTF_8) shouldBe
  """
  animals:
  - type: "com.charleskorn.kaml.Animal.Dog"
  name: "Spock"
 
  """.trimIndent()
  }
  }
 
  it("should support polymorphic writing with tag") {
  with(
  Yaml(
  configuration = YamlConfiguration(
  polymorphismStyle = PolymorphismStyle.Tag,
  ),
  ),
  ) {
  val output = ByteArrayOutputStream()
  encodeToStream(Animals.serializer(), Animals(listOf(Animal.Dog("Spock"))), output)
 
  output.toString(Charsets.UTF_8) shouldBe
  """
  animals:
  - !<com.charleskorn.kaml.Animal.Dog>
  name: "Spock"
 
  """.trimIndent()
  }
  }
 
  it("should support polymorphic writing no tag or property") {
  with(
  Yaml(
  configuration = YamlConfiguration(
  polymorphismStyle = PolymorphismStyle.None,
  ),
  ),
  ) {
  val output = ByteArrayOutputStream()
  encodeToStream(Animals.serializer(), Animals(listOf(Animal.Dog("Spock"))), output)
 
  output.toString(Charsets.UTF_8) shouldBe
  """
  animals:
  - name: "Spock"
 
  """.trimIndent()
  }
  }
  }
 
  describe("writing to a stream via generic extension function") {
@@ -115,3 178,15 @@ class JvmYamlWritingTest : DescribeSpec({
  }
  }
 })
 
 @Serializable
 class Animals(val animals: List<Animal>)
 
 @Serializable
 sealed interface Animal {
  @Serializable
  data class Dog(val name: String) : Animal
 
  @Serializable
  data class Cat(val name: String) : Animal
 }