generateForAnnotatedElement method

@override String generateForAnnotatedElement(Element element, ConstantReader annotation, BuildStep buildStep)

Implement to return source code to generate for element.

This method is invoked based on finding elements annotated with an instance of T. The annotation is provided as a ConstantReader.

Supported return values include a single String or multiple String instances within an Iterable or Stream. It is also valid to return a Future of String, Iterable, or Stream.

Implementations should return null when no content is generated. Empty or whitespace-only String instances are also ignored.

Implementation

@override
String generateForAnnotatedElement(
    Element element, ConstantReader annotation, BuildStep buildStep) {
  if (element is! ClassElement) {
    throw InvalidGenerationSourceError(
      redError(
        'expected ClassElement, found ${element.runtimeType}\n${StackTrace.current}',
      ),
      element: element,
      todo: "only classes can be notated with `generateIsolate`",
    );
  }

  final isSharedIsolate = annotation.read("_isSharedIsolate").boolValue;

  if (isSharedIsolate) {
    final sharedIsolate = annotation.read("sharedIsolate").objectValue;

    final Set<DartType> sharedInstanse = HashSet();

    for (var field in element.fields)
      for (ElementAnnotation meta in field.metadata)
        if (meta.element?.displayName == "FromIsolate")
          sharedInstanse.add(field.declaration.type);

    final String key = sharedIsolate.getField("isolateId")!.toStringValue()!;
    final SharedIsolateElement sharedIsolateElement =
        SharedIsolateElement.generate(
      classElement: element,
      sharedIsolate: sharedIsolate,
      annotation: annotation,
      sharedInstanse: sharedInstanse,
    );

    final int count = sharedIsolate.getField("classCount")!.toIntValue()!;

    sharedIsolateMap.update(
      key,
      (value) => value..add(sharedIsolateElement),
      ifAbsent: () => [sharedIsolateElement],
    );

    if (sharedIsolateMap[key]!.length == count) {
      final classBuffer = StringBuffer();

      writeSharedIsolateWarperClasses(
        classBuffer,
        sharedIsolateMap[key]!,
        key.toLowerCase(),
      );

      writeSharedIsolateEntryPoint(
        classBuffer,
        sharedIsolateMap[key]!,
        key,
      );

      return classBuffer.toString();
    }

    return "";
  }

  final bool isSameType = annotation.read("isSameType").boolValue;

  final ClassElement classElement = element;

  final classBuffer = StringBuffer();

  final String isolateFuncName = "_${classElement.name}Isolate".toLowerCase();

  writeIsolateWarperClass(
    classBuffer,
    classElement,
    isolateFuncName,
    isSameType,
  );

  writeIsolateEntryPoint(classBuffer, classElement, isolateFuncName);

  return classBuffer.toString();
}