[kotlinx-metadata] Add extensions for type aliases.

libraries/kotlinx-metadata/klib/src/kotlinx/metadata/klib/impl/klibExtensionNodes.kt

@@ -33,6 +33,9 @@ internal val KmPackage.klibExtensions: KlibPackageExtension
 internal val KmModuleFragment.klibExtensions: KlibModuleFragmentExtension
     get() = visitExtensions(KlibModuleFragmentExtensionVisitor.TYPE) as KlibModuleFragmentExtension
 
+internal val KmTypeAlias.klibExtensions: KlibTypeAliasExtension
+    get() = visitExtensions(KlibTypeAliasExtensionVisitor.TYPE) as KlibTypeAliasExtension
+
 internal class KlibFunctionExtension : KlibFunctionExtensionVisitor(), KmFunctionExtension {
 
     val annotations: MutableList<KmAnnotation> = mutableListOf()
@@ -221,4 +224,17 @@ internal class KlibModuleFragmentExtension : KlibModuleFragmentExtensionVisitor(
         fqName?.let(visitor::visitFqName)
         className.forEach(visitor::visitClassName)
     }
+}
+
+internal class KlibTypeAliasExtension : KlibTypeAliasExtensionVisitor(), KmTypeAliasExtension {
+    var uniqId: UniqId? = null
+
+    override fun visitUniqId(uniqId: UniqId) {
+        this.uniqId = uniqId
+    }
+
+    override fun accept(visitor: KmTypeExtensionVisitor) {
+        require(visitor is KlibTypeAliasExtensionVisitor)
+        uniqId?.let(visitor::visitUniqId)
+    }
 }

libraries/kotlinx-metadata/klib/src/kotlinx/metadata/klib/impl/klibMetadataExtensions.kt

@@ -126,6 +126,14 @@ internal class KlibMetadataExtensions : MetadataExtensions {
         }
     }
 
+    override fun readTypeAliasExtensions(v: KmTypeAliasVisitor, proto: ProtoBuf.TypeAlias, c: ReadContext) {
+        val extension = v.visitExtensions(KlibTypeAliasExtensionVisitor.TYPE) as? KlibTypeAliasExtensionVisitor ?: return
+
+        proto.getExtension(KlibMetadataProtoBuf.typeAliasUniqId).let { descriptorUniqId ->
+            extension.visitUniqId(descriptorUniqId.readUniqId())
+        }
+    }
+
     override fun writeClassExtensions(type: KmExtensionType, proto: ProtoBuf.Class.Builder, c: WriteContext): KmClassExtensionVisitor? {
         if (type != KlibClassExtensionVisitor.TYPE) return null
         return object : KlibClassExtensionVisitor() {
@@ -324,6 +332,22 @@ internal class KlibMetadataExtensions : MetadataExtensions {
         }
     }
 
+    override fun writeTypeAliasExtensions(
+        type: KmExtensionType,
+        proto: ProtoBuf.TypeAlias.Builder,
+        c: WriteContext
+    ): KmTypeAliasExtensionVisitor? {
+        if (type != KlibTypeAliasExtensionVisitor.TYPE) return null
+        return object : KlibTypeAliasExtensionVisitor() {
+            override fun visitUniqId(uniqId: UniqId) {
+                proto.setExtension(
+                    KlibMetadataProtoBuf.typeAliasUniqId,
+                    uniqId.writeUniqId().build()
+                )
+            }
+        }
+    }
+
     override fun createClassExtension(): KmClassExtension =
         KlibClassExtension()
 
@@ -347,4 +371,7 @@ internal class KlibMetadataExtensions : MetadataExtensions {
 
     override fun createTypeExtension(): KmTypeExtension =
         KlibTypeExtension()
+
+    override fun createTypeAliasExtension(): KmTypeAliasExtension =
+        KlibTypeAliasExtension()
 }

libraries/kotlinx-metadata/klib/src/kotlinx/metadata/klib/klibExtensions.kt

@@ -99,6 +99,12 @@ val KmTypeParameter.annotations: MutableList<KmAnnotation>
     get() = klibExtensions.annotations
 
 var KmTypeParameter.uniqId: UniqId?
+    get() = klibExtensions.uniqId
+    set(value) {
+        klibExtensions.uniqId = value
+    }
+
+var KmTypeAlias.uniqId: UniqId?
     get() = klibExtensions.uniqId
     set(value) {
         klibExtensions.uniqId = value

libraries/kotlinx-metadata/klib/src/kotlinx/metadata/klib/klibMetadataExtensionVisitors.kt

@@ -127,4 +127,16 @@ abstract class KlibModuleFragmentExtensionVisitor : KmModuleFragmentExtensionVis
     companion object {
         val TYPE = KmExtensionType(KlibModuleFragmentExtensionVisitor::class)
     }
+}
+
+abstract class KlibTypeAliasExtensionVisitor : KmTypeAliasExtensionVisitor {
+
+    abstract fun visitUniqId(uniqId: UniqId)
+
+    override val type: KmExtensionType
+        get() = TYPE
+
+    companion object {
+        val TYPE = KmExtensionType(KlibTypeAliasExtensionVisitor::class)
+    }
 }