private NamedFunctionDescriptorImpl createFunctionDescriptor(
JetFunctionLiteralExpression expression,
ExpressionTypingContext context,
boolean functionTypeExpected) {
JetFunctionLiteral functionLiteral = expression.getFunctionLiteral();
JetTypeReference receiverTypeRef = functionLiteral.getReceiverTypeRef();
NamedFunctionDescriptorImpl functionDescriptor =
new NamedFunctionDescriptorImpl(
context.scope.getContainingDeclaration(),
Collections.<AnnotationDescriptor>emptyList(),
"<anonymous>",
CallableMemberDescriptor.Kind.DECLARATION);
List<ValueParameterDescriptor> valueParameterDescriptors =
createValueParameterDescriptors(
context, functionLiteral, functionDescriptor, functionTypeExpected);
JetType effectiveReceiverType;
if (receiverTypeRef == null) {
if (functionTypeExpected) {
effectiveReceiverType = JetStandardClasses.getReceiverType(context.expectedType);
} else {
effectiveReceiverType = null;
}
} else {
effectiveReceiverType = context.getTypeResolver().resolveType(context.scope, receiverTypeRef);
}
functionDescriptor.initialize(
effectiveReceiverType,
NO_RECEIVER,
Collections.<TypeParameterDescriptor>emptyList(),
valueParameterDescriptors,
null,
Modality.FINAL,
Visibility.LOCAL);
context.trace.record(BindingContext.FUNCTION, expression, functionDescriptor);
return functionDescriptor;
}
@Override
public JetType visitFunctionLiteralExpression(
JetFunctionLiteralExpression expression, ExpressionTypingContext context) {
JetFunctionLiteral functionLiteral = expression.getFunctionLiteral();
JetBlockExpression bodyExpression = functionLiteral.getBodyExpression();
if (bodyExpression == null) return null;
JetType expectedType = context.expectedType;
boolean functionTypeExpected =
expectedType != TypeUtils.NO_EXPECTED_TYPE
&& JetStandardClasses.isFunctionType(expectedType);
NamedFunctionDescriptorImpl functionDescriptor =
createFunctionDescriptor(expression, context, functionTypeExpected);
List<JetType> parameterTypes = Lists.newArrayList();
List<ValueParameterDescriptor> valueParameters = functionDescriptor.getValueParameters();
for (ValueParameterDescriptor valueParameter : valueParameters) {
parameterTypes.add(valueParameter.getOutType());
}
ReceiverDescriptor receiverParameter = functionDescriptor.getReceiverParameter();
JetType receiver = receiverParameter != NO_RECEIVER ? receiverParameter.getType() : null;
JetType returnType = TypeUtils.NO_EXPECTED_TYPE;
JetScope functionInnerScope =
FunctionDescriptorUtil.getFunctionInnerScope(
context.scope, functionDescriptor, context.trace);
JetTypeReference returnTypeRef = functionLiteral.getReturnTypeRef();
if (returnTypeRef != null) {
returnType = context.getTypeResolver().resolveType(context.scope, returnTypeRef);
context
.getServices()
.checkFunctionReturnType(
expression,
context
.replaceScope(functionInnerScope)
.replaceExpectedType(returnType)
.replaceExpectedReturnType(returnType)
.replaceDataFlowInfo(context.dataFlowInfo));
} else {
if (functionTypeExpected) {
returnType = JetStandardClasses.getReturnTypeFromFunctionType(expectedType);
}
returnType =
context
.getServices()
.getBlockReturnedType(
functionInnerScope,
bodyExpression,
CoercionStrategy.COERCION_TO_UNIT,
context.replaceExpectedType(returnType).replaceExpectedReturnType(returnType));
}
JetType safeReturnType =
returnType == null ? ErrorUtils.createErrorType("<return type>") : returnType;
functionDescriptor.setReturnType(safeReturnType);
boolean hasDeclaredValueParameters = functionLiteral.getValueParameterList() != null;
if (!hasDeclaredValueParameters && functionTypeExpected) {
JetType expectedReturnType = JetStandardClasses.getReturnTypeFromFunctionType(expectedType);
if (JetStandardClasses.isUnit(expectedReturnType)) {
functionDescriptor.setReturnType(JetStandardClasses.getUnitType());
return DataFlowUtils.checkType(
JetStandardClasses.getFunctionType(
Collections.<AnnotationDescriptor>emptyList(),
receiver,
parameterTypes,
JetStandardClasses.getUnitType()),
expression,
context);
}
}
return DataFlowUtils.checkType(
JetStandardClasses.getFunctionType(
Collections.<AnnotationDescriptor>emptyList(),
receiver,
parameterTypes,
safeReturnType),
expression,
context);
}