Expression _dummyValue()

in lib/src/builder.dart [1064:1130]
56 lines of code
18 McCabe index (conditional complexity)

  Expression _dummyValue(analyzer.DartType type) {
    if (type is analyzer.FunctionType) {
      return _dummyFunctionValue(type);
    }

    if (type is! analyzer.InterfaceType) {
      // TODO(srawlins): This case is not known.
      return literalNull;
    }

    var typeArguments = type.typeArguments;
    if (type.isDartCoreBool) {
      return literalFalse;
    } else if (type.isDartCoreDouble) {
      return literalNum(0.0);
    } else if (type.isDartCoreFunction) {
      return refer('() {}');
    } else if (type.isDartAsyncFuture || type.isDartAsyncFutureOr) {
      final typeArgument = typeArguments.first;
      final futureValueArguments =
          typeSystem.isPotentiallyNonNullable(typeArgument)
              ? [_dummyValue(typeArgument)]
              : <Expression>[];
      return _futureReference(_typeReference(typeArgument))
          .property('value')
          .call(futureValueArguments);
    } else if (type.isDartCoreInt) {
      return literalNum(0);
    } else if (type.isDartCoreIterable || type.isDartCoreList) {
      assert(typeArguments.length == 1);
      final elementType = _typeReference(typeArguments[0]);
      return literalList([], elementType);
    } else if (type.isDartCoreMap) {
      assert(typeArguments.length == 2);
      final keyType = _typeReference(typeArguments[0]);
      final valueType = _typeReference(typeArguments[1]);
      return literalMap({}, keyType, valueType);
    } else if (type.isDartCoreNum) {
      return literalNum(0);
    } else if (type.isDartCoreSet) {
      assert(typeArguments.length == 1);
      final elementType = _typeReference(typeArguments[0]);
      return literalSet({}, elementType);
    } else if (type.element.declaration == typeProvider.streamElement) {
      assert(typeArguments.length == 1);
      final elementType = _typeReference(typeArguments[0]);
      return TypeReference((b) {
        b
          ..symbol = 'Stream'
          ..types.add(elementType);
      }).property('empty').call([]);
    } else if (type.isDartCoreString) {
      return literalString('');
    } else if (type.isDartTypedDataList) {
      // These "List" types from dart:typed_data are "non-subtypeable", but they
      // have predicatble constructors; each has an unnamed constructor which
      // takes a single int argument.
      return referImported(type.displayName, 'dart:typed_data')
          .call([literalNum(0)]);
      // TODO(srawlins): Do other types from typed_data have a "non-subtypeable"
      // restriction as well?
    }

    // This class is unknown; we must likely generate a fake class, and return
    // an instance here.
    return _dummyValueImplementing(type);
  }