Merge pull request #247 from nefilim/main

Add quoted scalar and multi line Style configurable support

Author: charleskorn

src/commonMain/kotlin/com/charleskorn/kaml/YamlConfiguration.kt

@@ -40,7 +40,9 @@ public data class YamlConfiguration constructor(
     internal val polymorphismPropertyName: String = "type",
     internal val encodingIndentationSize: Int = 2,
     internal val breakScalarsAt: Int = 80,
-    internal val sequenceStyle: SequenceStyle = SequenceStyle.Block
+    internal val sequenceStyle: SequenceStyle = SequenceStyle.Block,
+    internal val singleLineScalarStyle: SingleLineStringStyle = SingleLineStringStyle.DoubleQuoted,
+    internal val multiLineStringStyle: MultiLineStringStyle = singleLineScalarStyle.multiLineStringStyle,
 )
 
 public enum class PolymorphismStyle {
@@ -67,3 +69,20 @@ public enum class SequenceStyle {
      */
     Flow
 }
+
+public enum class MultiLineStringStyle {
+    Literal,
+    DoubleQuoted,
+    SingleQuoted,
+}
+
+public enum class SingleLineStringStyle {
+    DoubleQuoted,
+    SingleQuoted;
+
+    public val multiLineStringStyle: MultiLineStringStyle
+        get() = when (this) {
+            DoubleQuoted -> MultiLineStringStyle.DoubleQuoted
+            SingleQuoted -> MultiLineStringStyle.SingleQuoted
+        }
+}

src/jvmMain/kotlin/com/charleskorn/kaml/YamlOutput.kt

@@ -66,7 +66,7 @@ internal class YamlOutput(
     override fun encodeNull() = emitPlainScalar("null")
     override fun encodeBoolean(value: Boolean) = emitPlainScalar(value.toString())
     override fun encodeByte(value: Byte) = emitPlainScalar(value.toString())
-    override fun encodeChar(value: Char) = emitQuotedScalar(value.toString())
+    override fun encodeChar(value: Char) = emitQuotedScalar(value.toString(), configuration.singleLineScalarStyle.scalarStyle)
     override fun encodeDouble(value: Double) = emitPlainScalar(value.toString())
     override fun encodeFloat(value: Float) = emitPlainScalar(value.toString())
     override fun encodeInt(value: Int) = emitPlainScalar(value.toString())
@@ -77,14 +77,17 @@ internal class YamlOutput(
             currentTypeName = value
             shouldReadTypeName = false
         } else {
-            emitQuotedScalar(value)
+            when {
+                value.contains('\n') -> emitQuotedScalar(value, configuration.multiLineStringStyle.scalarStyle)
+                else -> emitQuotedScalar(value, configuration.singleLineScalarStyle.scalarStyle)
+            }
         }
     }
 
-    override fun encodeEnum(enumDescriptor: SerialDescriptor, index: Int) = emitQuotedScalar(enumDescriptor.getElementName(index))
+    override fun encodeEnum(enumDescriptor: SerialDescriptor, index: Int) = emitQuotedScalar(enumDescriptor.getElementName(index), configuration.singleLineScalarStyle.scalarStyle)
 
     private fun emitPlainScalar(value: String) = emitScalar(value, ScalarStyle.PLAIN)
-    private fun emitQuotedScalar(value: String) = emitScalar(value, ScalarStyle.DOUBLE_QUOTED)
+    private fun emitQuotedScalar(value: String, scalarStyle: ScalarStyle) = emitScalar(value, scalarStyle)
 
     override fun encodeElement(descriptor: SerialDescriptor, index: Int): Boolean {
         if (descriptor.kind is StructureKind.CLASS) {
@@ -111,7 +114,7 @@ internal class YamlOutput(
 
                         if (typeName.isPresent) {
                             emitPlainScalar(configuration.polymorphismPropertyName)
-                            emitQuotedScalar(typeName.get())
+                            emitQuotedScalar(typeName.get(), SingleLineStringStyle.DoubleQuoted.scalarStyle)
                         }
                     }
                 }
@@ -162,6 +165,19 @@ internal class YamlOutput(
             SequenceStyle.Flow -> FlowStyle.FLOW
         }
 
+    private val MultiLineStringStyle.scalarStyle: ScalarStyle
+        get() = when (this) {
+            MultiLineStringStyle.DoubleQuoted -> ScalarStyle.DOUBLE_QUOTED
+            MultiLineStringStyle.SingleQuoted -> ScalarStyle.SINGLE_QUOTED
+            MultiLineStringStyle.Literal -> ScalarStyle.LITERAL
+        }
+
+    private val SingleLineStringStyle.scalarStyle: ScalarStyle
+        get() = when (this) {
+            SingleLineStringStyle.DoubleQuoted -> ScalarStyle.DOUBLE_QUOTED
+            SingleLineStringStyle.SingleQuoted -> ScalarStyle.SINGLE_QUOTED
+        }
+
     companion object {
         private val ALL_IMPLICIT = ImplicitTuple(true, true)
         private val ALL_EXPLICIT = ImplicitTuple(false, false)

src/jvmTest/kotlin/com/charleskorn/kaml/JvmYamlWritingTest.kt

@@ -28,12 +28,87 @@ import java.io.ByteArrayOutputStream
 object JvmYamlWritingTest : Spek({
     describe("JVM-specific extensions for YAML writing") {
         describe("writing to a stream") {
-            val output = ByteArrayOutputStream()
-            Yaml.default.encodeToStream(String.serializer(), "hello world", output)
-
             it("returns the value serialized in the expected YAML form") {
+                val output = ByteArrayOutputStream()
+                Yaml.default.encodeToStream(String.serializer(), "hello world", output)
+
                 expect(output.toString(Charsets.UTF_8)).toEqual("\"hello world\"\n")
             }
+
+            it("should support block literal style output for multiline strings when configured") {
+                with(
+                    Yaml(
+                        configuration = YamlConfiguration(
+                            multiLineStringStyle = MultiLineStringStyle.Literal,
+                        )
+                    )
+                ) {
+                    val output = ByteArrayOutputStream()
+                    encodeToStream(String.serializer(), "hello\nworld\nhow are | you?\n", output)
+
+                    expect(output.toString(Charsets.UTF_8)).toEqual(
+                        """
+                           |
+                             hello
+                             world
+                             how are | you?
+
+                        """.trimIndent()
+                    )
+                }
+
+                with(
+                    Yaml(
+                        configuration = YamlConfiguration(
+                            multiLineStringStyle = MultiLineStringStyle.DoubleQuoted,
+                        )
+                    )
+                ) {
+                    val output = ByteArrayOutputStream()
+                    encodeToStream(String.serializer(), "hello\nworld\nhow are | you?\n", output)
+                    expect(output.toString(Charsets.UTF_8)).toEqual(
+                        """|"hello\nworld\nhow are | you?\n"
+                           |
+                        """.trimMargin()
+                    )
+                }
+            }
+
+            it("should support configurable scalar quoting") {
+                with(
+                    Yaml(
+                        configuration = YamlConfiguration(
+                            singleLineScalarStyle = SingleLineStringStyle.SingleQuoted
+                        )
+                    )
+                ) {
+                    val output = ByteArrayOutputStream()
+                    encodeToStream(String.serializer(), "hello, world", output)
+
+                    expect(output.toString(Charsets.UTF_8)).toEqual(
+                        """|'hello, world'
+                           |
+                        """.trimMargin()
+                    )
+                }
+
+                with(
+                    Yaml(
+                        configuration = YamlConfiguration(
+                            singleLineScalarStyle = SingleLineStringStyle.DoubleQuoted
+                        )
+                    )
+                ) {
+                    val output = ByteArrayOutputStream()
+                    encodeToStream(String.serializer(), "hello, world", output)
+
+                    expect(output.toString(Charsets.UTF_8)).toEqual(
+                        """|"hello, world"
+                           |
+                        """.trimMargin()
+                    )
+                }
+            }
         }
     }
 })