Add more utils

lib/src/main/kotlin/me/eugeniomarletti/kotlin/metadata/Constants.kt

@@ -4,3 +4,4 @@ package me.eugeniomarletti.kotlin.metadata
 
 const val kaptGeneratedOption = "kapt.kotlin.generated"
 const val kotlinMetadataAnnotation = "kotlin.Metadata"
+const val kotlinPropertyAnnotationsFunPostfix = "\$annotations"

lib/src/main/kotlin/me/eugeniomarletti/kotlin/metadata/JvmUtils.kt

@@ -0,0 +1,18 @@
+package me.eugeniomarletti.kotlin.metadata
+
+import org.jetbrains.kotlin.serialization.ProtoBuf
+import org.jetbrains.kotlin.serialization.deserialization.NameResolver
+import org.jetbrains.kotlin.serialization.deserialization.TypeTable
+import org.jetbrains.kotlin.serialization.jvm.JvmProtoBufUtil
+
+/**
+ * Returns JVM signature in the format: "equals(Ljava/lang/Object;)Z"
+ */
+fun ProtoBuf.Function.getJvmMethodSignature(nameResolver: NameResolver, typeTable: ProtoBuf.TypeTable = this.typeTable) =
+    JvmProtoBufUtil.getJvmMethodSignature(this, nameResolver, TypeTable(typeTable))
+
+fun ProtoBuf.Constructor.getJvmConstructorSignature(nameResolver: NameResolver, typeTable: ProtoBuf.TypeTable) =
+    JvmProtoBufUtil.getJvmConstructorSignature(this, nameResolver, TypeTable(typeTable))
+
+fun ProtoBuf.Property.getJvmFieldSignature(nameResolver: NameResolver, typeTable: ProtoBuf.TypeTable) =
+    JvmProtoBufUtil.getJvmFieldSignature(this, nameResolver, TypeTable(typeTable))

lib/src/main/kotlin/me/eugeniomarletti/kotlin/metadata/ProcessingUtils.kt

@@ -0,0 +1,71 @@
+package me.eugeniomarletti.kotlin.metadata
+
+import me.eugeniomarletti.kotlin.processing.KotlinProcessingUtils
+import javax.lang.model.element.ExecutableElement
+import javax.lang.model.element.TypeElement
+import javax.lang.model.type.ArrayType
+import javax.lang.model.type.DeclaredType
+import javax.lang.model.type.ErrorType
+import javax.lang.model.type.ExecutableType
+import javax.lang.model.type.NoType
+import javax.lang.model.type.NullType
+import javax.lang.model.type.PrimitiveType
+import javax.lang.model.type.TypeKind
+import javax.lang.model.type.TypeMirror
+import javax.lang.model.type.TypeVariable
+import javax.lang.model.type.WildcardType
+import javax.lang.model.util.AbstractTypeVisitor6
+import javax.lang.model.util.Types
+
+interface KotlinMetadataUtils : KotlinProcessingUtils {
+
+    val ExecutableElement.jvmMethodSignature: String get() {
+        fun TypeMirror.jvmDeclaration(): String = accept(JvmDeclarationTypeVisitor, typeUtils)
+        val params = parameters.joinToString(separator = "") { it.asType().jvmDeclaration() }
+        val returnType = returnType.jvmDeclaration()
+        return "$simpleName($params)$returnType"
+    }
+}
+
+/**
+ * When applied over a method, it returns the JVM signature in the form "name(descriptor)returnValue", for example: "equals(Ljava/lang/Object;)Z".
+ *
+ * See the [JVM specification, section 4.3](http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.3)
+ * @see getJvmMethodSignature
+ */
+private object JvmDeclarationTypeVisitor : AbstractTypeVisitor6<String, Types>() {
+
+    override fun visitTypeVariable(t: TypeVariable, typeUtils: Types): String =
+        typeUtils.erasure(t).accept(this, typeUtils)
+
+    override fun visitArray(t: ArrayType, typeUtils: Types): String =
+        "[" + t.componentType.accept(this, typeUtils)
+
+    override fun visitNoType(t: NoType, typeUtils: Types): String =
+        "V"
+
+    override fun visitDeclared(t: DeclaredType, typeUtils: Types): String {
+        val internalName = (t.asElement() as TypeElement).qualifiedName.toString().replace('.', '/')
+        return "L$internalName;"
+    }
+
+    override fun visitPrimitive(t: PrimitiveType, typeUtils: Types): String =
+        when (t.kind) {
+            TypeKind.BYTE -> "B"
+            TypeKind.CHAR -> "C"
+            TypeKind.DOUBLE -> "D"
+            TypeKind.FLOAT -> "F"
+            TypeKind.INT -> "I"
+            TypeKind.LONG -> "J"
+            TypeKind.SHORT -> "S"
+            TypeKind.BOOLEAN -> "Z"
+            else -> error("Unknown primitive type $t")
+        }
+
+    override fun visitExecutable(t: ExecutableType, typeUtils: Types): String = visitUnknown(t, typeUtils)
+    override fun visitWildcard(t: WildcardType, typeUtils: Types): String = visitUnknown(t, typeUtils)
+    override fun visitError(t: ErrorType, typeUtils: Types): String = visitUnknown(t, typeUtils)
+    override fun visitNull(t: NullType, typeUtils: Types): String = visitUnknown(t, typeUtils)
+
+    override fun visitUnknown(t: TypeMirror, typeUtils: Types): String = error("Unsupported type $t")
+}

lib/src/main/kotlin/me/eugeniomarletti/kotlin/metadata/ProtoExtensions.kt

@@ -0,0 +1,19 @@
+package me.eugeniomarletti.kotlin.metadata
+
+import org.jetbrains.kotlin.protobuf.GeneratedMessageLite.ExtendableMessage
+import org.jetbrains.kotlin.protobuf.GeneratedMessageLite.GeneratedExtension
+import org.jetbrains.kotlin.serialization.ProtoBuf
+import org.jetbrains.kotlin.serialization.jvm.JvmProtoBuf
+
+fun <MessageType : ExtendableMessage<MessageType>, Type>
+    MessageType.getExtensionOrNull(extension: GeneratedExtension<MessageType, Type>)
+    = takeIf { hasExtension(extension) }?.let { getExtension(extension) }
+
+val ProtoBuf.Constructor.jvmConstructorSignature get() = getExtensionOrNull(JvmProtoBuf.constructorSignature)
+val ProtoBuf.Function.jvmMethodSignature get() = getExtensionOrNull(JvmProtoBuf.methodSignature)
+val ProtoBuf.Property.jvmPropertySignature get() = getExtensionOrNull(JvmProtoBuf.propertySignature)
+val ProtoBuf.Type.jvmTypeAnnotation get() = getExtensionOrNull(JvmProtoBuf.typeAnnotation) as List<ProtoBuf.Annotation>?
+val ProtoBuf.Type.jvmIsRaw get() = getExtensionOrNull(JvmProtoBuf.isRaw)
+val ProtoBuf.TypeParameter.jvmTypeParameterAnnotation get() = getExtensionOrNull(JvmProtoBuf.typeParameterAnnotation) as List<ProtoBuf.Annotation>?
+val ProtoBuf.Class.jvmClassModuleName get() = getExtensionOrNull(JvmProtoBuf.classModuleName)
+val ProtoBuf.Package.jvmPackageModuleName get() = getExtensionOrNull(JvmProtoBuf.packageModuleName)

lib/src/main/kotlin/me/eugeniomarletti/kotlin/processing/KotlinAbstractProcessor.kt

@@ -0,0 +1,42 @@
+package me.eugeniomarletti.kotlin.processing
+
+import java.util.Locale
+import javax.annotation.processing.AbstractProcessor
+import javax.annotation.processing.Completion
+import javax.annotation.processing.Filer
+import javax.annotation.processing.Messager
+import javax.annotation.processing.ProcessingEnvironment
+import javax.annotation.processing.RoundEnvironment
+import javax.lang.model.SourceVersion
+import javax.lang.model.element.AnnotationMirror
+import javax.lang.model.element.Element
+import javax.lang.model.element.ExecutableElement
+import javax.lang.model.element.TypeElement
+import javax.lang.model.util.Elements
+import javax.lang.model.util.Types
+
+abstract class KotlinAbstractProcessor : AbstractProcessor(), KotlinProcessingUtils {
+
+    override fun getSupportedOptions(): Set<String> = super.getSupportedOptions()
+    override fun getSupportedSourceVersion(): SourceVersion = super.getSupportedSourceVersion()
+    override fun getSupportedAnnotationTypes(): Set<String> = super.getSupportedAnnotationTypes()
+    override fun init(processingEnv: ProcessingEnvironment) = super.init(processingEnv)
+
+    override fun getCompletions(
+        element: Element?,
+        annotation: AnnotationMirror?,
+        member: ExecutableElement?,
+        userText: String?
+    ): Iterable<Completion>
+        = super.getCompletions(element, annotation, member, userText)
+
+    override abstract fun process(annotations: Set<TypeElement>, roundEnv: RoundEnvironment): Boolean
+
+    override val options: Map<String, String> get() = processingEnv.options
+    override val messager: Messager get() = processingEnv.messager
+    override val filer: Filer get() = processingEnv.filer
+    override val elementUtils: Elements get() = processingEnv.elementUtils
+    override val typeUtils: Types get() = processingEnv.typeUtils
+    override val sourceVersion: SourceVersion get() = processingEnv.sourceVersion
+    override val locale: Locale get() = processingEnv.locale
+}

lib/src/main/kotlin/me/eugeniomarletti/kotlin/processing/KotlinProcessingUtils.kt

@@ -0,0 +1,18 @@
+package me.eugeniomarletti.kotlin.processing
+
+import java.util.Locale
+import javax.annotation.processing.Filer
+import javax.annotation.processing.Messager
+import javax.lang.model.SourceVersion
+import javax.lang.model.util.Elements
+import javax.lang.model.util.Types
+
+interface KotlinProcessingUtils {
+    val options: Map<String, String>
+    val messager: Messager
+    val filer: Filer
+    val elementUtils: Elements
+    val typeUtils: Types
+    val sourceVersion: SourceVersion
+    val locale: Locale
+}