/**
* Infer the parameter and return types of a function from the parameter and return types of the
* function it is overriding.
*
* @param oldType The function being overridden. Does nothing if this is null.
* @param paramsParent The LP node of the function that we're assigning to. If null, that just
* means we're not initializing this to a function literal.
*/
FunctionTypeBuilder inferFromOverriddenFunction(
@Nullable FunctionType oldType, @Nullable Node paramsParent) {
if (oldType == null) {
return this;
}
returnType = oldType.getReturnType();
returnTypeInferred = oldType.isReturnTypeInferred();
if (paramsParent == null) {
// Not a function literal.
parametersNode = oldType.getParametersNode();
if (parametersNode == null) {
parametersNode = new FunctionParamBuilder(typeRegistry).build();
}
} else {
// We're overriding with a function literal. Apply type information
// to each parameter of the literal.
FunctionParamBuilder paramBuilder = new FunctionParamBuilder(typeRegistry);
Iterator<Node> oldParams = oldType.getParameters().iterator();
boolean warnedAboutArgList = false;
boolean oldParamsListHitOptArgs = false;
for (Node currentParam = paramsParent.getFirstChild();
currentParam != null;
currentParam = currentParam.getNext()) {
if (oldParams.hasNext()) {
Node oldParam = oldParams.next();
Node newParam = paramBuilder.newParameterFromNode(oldParam);
oldParamsListHitOptArgs =
oldParamsListHitOptArgs || oldParam.isVarArgs() || oldParam.isOptionalArg();
// The subclass method might right its var_args as individual
// arguments.
if (currentParam.getNext() != null && newParam.isVarArgs()) {
newParam.setVarArgs(false);
newParam.setOptionalArg(true);
}
} else {
warnedAboutArgList |=
addParameter(
paramBuilder,
typeRegistry.getNativeType(UNKNOWN_TYPE),
warnedAboutArgList,
codingConvention.isOptionalParameter(currentParam) || oldParamsListHitOptArgs,
codingConvention.isVarArgsParameter(currentParam));
}
}
parametersNode = paramBuilder.build();
}
return this;
}
