/**
* @param function
* @return the Definition object for the function.
*/
private Definition getFunctionDefinition(Node function) {
DefinitionSite definitionSite = defFinder.getDefinitionForFunction(function);
Preconditions.checkNotNull(definitionSite);
Definition definition = definitionSite.definition;
Preconditions.checkState(!definitionSite.inExterns);
Preconditions.checkState(definition.getRValue() == function);
return definition;
}
/**
* @return Whether the definitionSite represents a function whose call signature can be
* modified.
*/
private boolean canChangeSignature(Node function) {
Definition definition = getFunctionDefinition(function);
CodingConvention convention = compiler.getCodingConvention();
Preconditions.checkState(!definition.isExtern());
Collection<UseSite> useSites = defFinder.getUseSites(definition);
for (UseSite site : useSites) {
Node parent = site.node.getParent();
// This was a use site removed by something else before we run.
// 1. By another pass before us which means the definition graph is
// no updated properly.
// 2. By the continuations algorithm above.
if (parent == null) {
continue; // Ignore it.
}
// Ignore references within goog.inherits calls.
if (NodeUtil.isCall(parent) && convention.getClassesDefinedByCall(parent) != null) {
continue;
}
// Accessing the property directly prevents rewrite.
if (!SimpleDefinitionFinder.isCallOrNewSite(site)) {
if (!(NodeUtil.isGetProp(parent) && NodeUtil.isFunctionObjectCall(parent.getParent()))) {
return false;
}
}
if (NodeUtil.isFunctionObjectApply(parent)) {
return false;
}
// TODO(johnlenz): support specialization
// Multiple definitions prevent rewrite.
// Attempt to validate the state of the simple definition finder.
Node nameNode = site.node;
Collection<Definition> singleSiteDefinitions =
defFinder.getDefinitionsReferencedAt(nameNode);
Preconditions.checkState(singleSiteDefinitions.size() == 1);
Preconditions.checkState(singleSiteDefinitions.contains(definition));
}
return true;
}