UnqualifiedLookup::UnqualifiedLookup(DeclName Name, DeclContext *DC,
LazyResolver *TypeResolver,
bool IsKnownNonCascading,
SourceLoc Loc, bool IsTypeLookup,
bool AllowProtocolMembers) {
Module &M = *DC->getParentModule();
ASTContext &Ctx = M.getASTContext();
const SourceManager &SM = Ctx.SourceMgr;
DebuggerClient *DebugClient = M.getDebugClient();
NamedDeclConsumer Consumer(Name, Results, IsTypeLookup);
Optional<bool> isCascadingUse;
if (IsKnownNonCascading)
isCascadingUse = false;
SmallVector<UnqualifiedLookupResult, 4> UnavailableInnerResults;
// Never perform local lookup for operators.
if (Name.isOperator()) {
if (!isCascadingUse.hasValue()) {
isCascadingUse =
DC->isCascadingContextForLookup(/*excludeFunctions=*/true);
}
DC = DC->getModuleScopeContext();
} else {
// If we are inside of a method, check to see if there are any ivars in
// scope, and if so, whether this is a reference to one of them.
// FIXME: We should persist this information between lookups.
while (!DC->isModuleScopeContext()) {
ValueDecl *BaseDecl = 0;
ValueDecl *MetaBaseDecl = 0;
GenericParamList *GenericParams = nullptr;
Type ExtendedType;
if (auto *AFD = dyn_cast<AbstractFunctionDecl>(DC)) {
// Look for local variables; normally, the parser resolves these
// for us, but it can't do the right thing inside local types.
// FIXME: when we can parse and typecheck the function body partially
// for code completion, AFD->getBody() check can be removed.
if (Loc.isValid() && AFD->getBody()) {
if (!isCascadingUse.hasValue()) {
isCascadingUse =
!SM.rangeContainsTokenLoc(AFD->getBodySourceRange(), Loc);
}
namelookup::FindLocalVal localVal(SM, Loc, Consumer);
localVal.visit(AFD->getBody());
if (!Results.empty())
return;
for (auto *PL : AFD->getParameterLists())
localVal.checkParameterList(PL);
if (!Results.empty())
return;
}
if (!isCascadingUse.hasValue() || isCascadingUse.getValue())
isCascadingUse = AFD->isCascadingContextForLookup(false);
if (AFD->getExtensionType()) {
if (AFD->getDeclContext()->getAsProtocolOrProtocolExtensionContext()) {
ExtendedType = AFD->getDeclContext()->getSelfTypeInContext();
// Fallback path.
if (!ExtendedType)
ExtendedType = AFD->getExtensionType();
} else {
ExtendedType = AFD->getExtensionType();
}
BaseDecl = AFD->getImplicitSelfDecl();
MetaBaseDecl = AFD->getExtensionType()->getAnyNominal();
DC = DC->getParent();
if (auto *FD = dyn_cast<FuncDecl>(AFD))
if (FD->isStatic())
ExtendedType = MetatypeType::get(ExtendedType);
// If we're not in the body of the function, the base declaration
// is the nominal type, not 'self'.
if (Loc.isValid() &&
AFD->getBodySourceRange().isValid() &&
!SM.rangeContainsTokenLoc(AFD->getBodySourceRange(), Loc)) {
BaseDecl = MetaBaseDecl;
}
}
// Look in the generic parameters after checking our local declaration.
GenericParams = AFD->getGenericParams();
} else if (auto *ACE = dyn_cast<AbstractClosureExpr>(DC)) {
// Look for local variables; normally, the parser resolves these
// for us, but it can't do the right thing inside local types.
if (Loc.isValid()) {
if (auto *CE = dyn_cast<ClosureExpr>(ACE)) {
namelookup::FindLocalVal localVal(SM, Loc, Consumer);
localVal.visit(CE->getBody());
if (!Results.empty())
return;
localVal.checkParameterList(CE->getParameters());
if (!Results.empty())
return;
}
}
if (!isCascadingUse.hasValue())
isCascadingUse = ACE->isCascadingContextForLookup(false);
} else if (ExtensionDecl *ED = dyn_cast<ExtensionDecl>(DC)) {
ExtendedType = ED->getSelfTypeInContext();
BaseDecl = ED->getAsNominalTypeOrNominalTypeExtensionContext();
MetaBaseDecl = BaseDecl;
if (!isCascadingUse.hasValue())
isCascadingUse = ED->isCascadingContextForLookup(false);
} else if (NominalTypeDecl *ND = dyn_cast<NominalTypeDecl>(DC)) {
ExtendedType = ND->getDeclaredType();
BaseDecl = ND;
MetaBaseDecl = BaseDecl;
if (!isCascadingUse.hasValue())
isCascadingUse = ND->isCascadingContextForLookup(false);
} else if (auto I = dyn_cast<DefaultArgumentInitializer>(DC)) {
// In a default argument, skip immediately out of both the
// initializer and the function.
isCascadingUse = false;
DC = I->getParent()->getParent();
continue;
} else {
assert(isa<TopLevelCodeDecl>(DC) || isa<Initializer>(DC));
if (!isCascadingUse.hasValue())
isCascadingUse = DC->isCascadingContextForLookup(false);
}
// Check the generic parameters for something with the given name.
if (GenericParams) {
namelookup::FindLocalVal localVal(SM, Loc, Consumer);
localVal.checkGenericParams(GenericParams);
if (!Results.empty())
return;
}
if (BaseDecl) {
if (TypeResolver)
TypeResolver->resolveDeclSignature(BaseDecl);
NLOptions options = NL_UnqualifiedDefault;
if (isCascadingUse.getValue())
options |= NL_KnownCascadingDependency;
else
options |= NL_KnownNonCascadingDependency;
if (AllowProtocolMembers)
options |= NL_ProtocolMembers;
if (IsTypeLookup)
options |= NL_OnlyTypes;
if (!ExtendedType)
ExtendedType = ErrorType::get(Ctx);
SmallVector<ValueDecl *, 4> Lookup;
DC->lookupQualified(ExtendedType, Name, options, TypeResolver, Lookup);
bool isMetatypeType = ExtendedType->is<AnyMetatypeType>();
bool FoundAny = false;
for (auto Result : Lookup) {
// If we're looking into an instance, skip static functions.
if (!isMetatypeType &&
isa<FuncDecl>(Result) &&
cast<FuncDecl>(Result)->isStatic())
continue;
// Classify this declaration.
FoundAny = true;
// Types are local or metatype members.
if (auto TD = dyn_cast<TypeDecl>(Result)) {
if (isa<GenericTypeParamDecl>(TD))
Results.push_back(UnqualifiedLookupResult(Result));
else
Results.push_back(UnqualifiedLookupResult(MetaBaseDecl, Result));
continue;
} else if (auto FD = dyn_cast<FuncDecl>(Result)) {
if (FD->isStatic() && !isMetatypeType)
continue;
} else if (isa<EnumElementDecl>(Result)) {
Results.push_back(UnqualifiedLookupResult(BaseDecl, Result));
continue;
}
Results.push_back(UnqualifiedLookupResult(BaseDecl, Result));
}
if (FoundAny) {
// Predicate that determines whether a lookup result should
// be unavailable except as a last-ditch effort.
auto unavailableLookupResult =
[&](const UnqualifiedLookupResult &result) {
return result.getValueDecl()->getAttrs()
.isUnavailableInCurrentSwift();
};
// If all of the results we found are unavailable, keep looking.
if (std::all_of(Results.begin(), Results.end(),
unavailableLookupResult)) {
UnavailableInnerResults.append(Results.begin(), Results.end());
Results.clear();
FoundAny = false;
} else {
if (DebugClient)
filterForDiscriminator(Results, DebugClient);
return;
}
}
// Check the generic parameters if our context is a generic type or
// extension thereof.
GenericParamList *dcGenericParams = nullptr;
if (auto nominal = dyn_cast<NominalTypeDecl>(DC))
dcGenericParams = nominal->getGenericParams();
else if (auto ext = dyn_cast<ExtensionDecl>(DC))
dcGenericParams = ext->getGenericParams();
if (dcGenericParams) {
namelookup::FindLocalVal localVal(SM, Loc, Consumer);
localVal.checkGenericParams(dcGenericParams);
if (!Results.empty())
return;
}
}
DC = DC->getParent();
}
if (!isCascadingUse.hasValue())
isCascadingUse = true;
}
if (auto SF = dyn_cast<SourceFile>(DC)) {
if (Loc.isValid()) {
// Look for local variables in top-level code; normally, the parser
// resolves these for us, but it can't do the right thing for
// local types.
namelookup::FindLocalVal localVal(SM, Loc, Consumer);
localVal.checkSourceFile(*SF);
if (!Results.empty())
return;
}
}
// TODO: Does the debugger client care about compound names?
if (Name.isSimpleName()
&& DebugClient && DebugClient->lookupOverrides(Name.getBaseName(), DC,
Loc, IsTypeLookup, Results))
return;
recordLookupOfTopLevelName(DC, Name, isCascadingUse.getValue());
// Add private imports to the extra search list.
SmallVector<Module::ImportedModule, 8> extraImports;
if (auto FU = dyn_cast<FileUnit>(DC))
FU->getImportedModules(extraImports, Module::ImportFilter::Private);
using namespace namelookup;
SmallVector<ValueDecl *, 8> CurModuleResults;
auto resolutionKind =
IsTypeLookup ? ResolutionKind::TypesOnly : ResolutionKind::Overloadable;
lookupInModule(&M, {}, Name, CurModuleResults, NLKind::UnqualifiedLookup,
resolutionKind, TypeResolver, DC, extraImports);
for (auto VD : CurModuleResults)
Results.push_back(UnqualifiedLookupResult(VD));
if (DebugClient)
filterForDiscriminator(Results, DebugClient);
// Now add any names the DebugClient knows about to the lookup.
if (Name.isSimpleName() && DebugClient)
DebugClient->lookupAdditions(Name.getBaseName(), DC, Loc, IsTypeLookup,
Results);
// If we've found something, we're done.
if (!Results.empty())
return;
// If we still haven't found anything, but we do have some
// declarations that are "unavailable in the current Swift", drop
// those in.
if (!UnavailableInnerResults.empty()) {
Results = std::move(UnavailableInnerResults);
return;
}
if (!Name.isSimpleName())
return;
// Look for a module with the given name.
if (Name.isSimpleName(M.getName())) {
Results.push_back(UnqualifiedLookupResult(&M));
return;
}
Module *desiredModule = Ctx.getLoadedModule(Name.getBaseName());
if (!desiredModule && Name == Ctx.TheBuiltinModule->getName())
desiredModule = Ctx.TheBuiltinModule;
if (desiredModule) {
forAllVisibleModules(DC, [&](const Module::ImportedModule &import) -> bool {
if (import.second == desiredModule) {
Results.push_back(UnqualifiedLookupResult(import.second));
return false;
}
return true;
});
}
}
