ast: default value support in generation

ast/src/main/ast/pork.yml

@@ -123,6 +123,7 @@ types:
       type: Symbol
     - name: multiple
       type: Boolean
+      defaultValue: "false"
   FunctionDefinition:
     parent: Definition
     values:

ast/src/main/kotlin/gay/pizza/pork/ast/ArgumentSpec.kt

@@ -6,4 +6,4 @@ import kotlinx.serialization.Serializable
 
 @Serializable
 @SerialName("argumentSpec")
-class ArgumentSpec(var symbol: Symbol, var multiple: Boolean)
+class ArgumentSpec(var symbol: Symbol, var multiple: Boolean = false)

buildext/src/main/kotlin/gay/pizza/pork/buildext/ast/AstCodegen.kt

@@ -241,6 +241,9 @@ class AstCodegen(val pkg: String, val outputDirectory: Path, val world: AstWorld
       for (value in type.values!!) {
         val member = KotlinMember(value.name, toKotlinType(value.typeRef))
         member.abstract = value.abstract
+        if (value.defaultValue != null) {
+          member.value = value.defaultValue
+        }
         if (type.isParentAbstract(value)) {
           member.overridden = true
         }
@@ -279,7 +282,9 @@ class AstCodegen(val pkg: String, val outputDirectory: Path, val world: AstWorld
         ),
         isImmediateExpression = true
       )
-      val anyListMembers = type.values?.any { it.typeRef.form == AstTypeRefForm.List } ?: false
+      val anyListMembers = type.values?.any {
+        it.typeRef.form == AstTypeRefForm.List
+      } ?: false
       val elideVisitChildren: Boolean
       if (anyListMembers) {
         val visitParameters = (type.values?.mapNotNull {

buildext/src/main/kotlin/gay/pizza/pork/buildext/ast/AstValue.kt

@@ -3,5 +3,6 @@ package gay.pizza.pork.buildext.ast
 class AstValue(
   val name: String,
   val typeRef: AstTypeRef,
-  val abstract: Boolean = false
+  val abstract: Boolean = false,
+  val defaultValue: String? = null
 )

buildext/src/main/kotlin/gay/pizza/pork/buildext/ast/AstValueDescription.kt

@@ -3,5 +3,6 @@ package gay.pizza.pork.buildext.ast
 data class AstValueDescription(
   val name: String,
   val type: String,
-  val required: Boolean = false
+  val required: Boolean = false,
+  val defaultValue: String? = null
 )

buildext/src/main/kotlin/gay/pizza/pork/buildext/ast/AstWorld.kt

@@ -59,7 +59,12 @@ class AstWorld {
           type.markHasValues()
           for (value in typeDescription.values) {
             val typeRef = AstTypeRef.parse(value.type, world.typeRegistry)
-            val typeValue = AstValue(value.name, typeRef, abstract = value.required)
+            val typeValue = AstValue(
+              value.name,
+              typeRef,
+              abstract = value.required,
+              defaultValue = value.defaultValue
+            )
             type.addValue(typeValue)
           }
         }