Google Git
Sign in
fuchsia / third_party / swift / e9f71fd61c9e3ea09253347ebb3dafee36041951 / . / lib / Sema / TypeCheckType.cpp
blob: 793e97812f4fd02f30c3b04de543aac06fa37310 [file] [log] [blame]
//===--- TypeCheckType.cpp - Type Validation ------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2018 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file implements validation for Swift types, emitting semantic errors as
// appropriate and checking default initializer values.
//
//===----------------------------------------------------------------------===//
#include "TypeChecker.h"
#include "GenericTypeResolver.h"
#include "TypeCheckAvailability.h"
#include "swift/Strings.h"
#include "swift/AST/ASTVisitor.h"
#include "swift/AST/ASTWalker.h"
#include "swift/AST/ExistentialLayout.h"
#include "swift/AST/ForeignErrorConvention.h"
#include "swift/AST/GenericEnvironment.h"
#include "swift/AST/NameLookup.h"
#include "swift/AST/ParameterList.h"
#include "swift/AST/PrettyStackTrace.h"
#include "swift/AST/ProtocolConformance.h"
#include "swift/AST/TypeLoc.h"
#include "swift/Basic/SourceManager.h"
#include "swift/Basic/Statistic.h"
#include "swift/Basic/StringExtras.h"
#include "swift/ClangImporter/ClangImporter.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/SaveAndRestore.h"
using namespace swift;
#define DEBUG_TYPE "TypeCheckType"
GenericTypeResolver::~GenericTypeResolver() { }
Type TypeChecker::getArraySliceType(SourceLoc loc, Type elementType) {
if (!Context.getArrayDecl()) {
diagnose(loc, diag::sugar_type_not_found, 0);
return Type();
}
return ArraySliceType::get(elementType);
}
Type TypeChecker::getDictionaryType(SourceLoc loc, Type keyType,
Type valueType) {
if (!Context.getDictionaryDecl()) {
diagnose(loc, diag::sugar_type_not_found, 3);
return Type();
}
return DictionaryType::get(keyType, valueType);
}
Type TypeChecker::getOptionalType(SourceLoc loc, Type elementType) {
if (!Context.getOptionalDecl()) {
diagnose(loc, diag::sugar_type_not_found, 1);
return Type();
}
return OptionalType::get(elementType);
}
static Type getPointerType(TypeChecker &tc, SourceLoc loc, Type pointeeType,
PointerTypeKind kind) {
auto pointerDecl = [&] {
switch (kind) {
case PTK_UnsafeMutableRawPointer:
case PTK_UnsafeRawPointer:
llvm_unreachable("these pointer types don't take arguments");
case PTK_UnsafePointer:
return tc.Context.getUnsafePointerDecl();
case PTK_UnsafeMutablePointer:
return tc.Context.getUnsafeMutablePointerDecl();
case PTK_AutoreleasingUnsafeMutablePointer:
return tc.Context.getAutoreleasingUnsafeMutablePointerDecl();
}
llvm_unreachable("bad kind");
}();
if (!pointerDecl) {
tc.diagnose(loc, diag::pointer_type_not_found,
kind == PTK_UnsafePointer ? 0 :
kind == PTK_UnsafeMutablePointer ? 1 : 2);
return Type();
}
tc.validateDecl(pointerDecl);
if (pointerDecl->isInvalid())
return Type();
// TODO: validate generic signature?
return BoundGenericType::get(pointerDecl, nullptr, pointeeType);
}
Type TypeChecker::getUnsafePointerType(SourceLoc loc, Type pointeeType) {
return getPointerType(*this, loc, pointeeType, PTK_UnsafePointer);
}
Type TypeChecker::getUnsafeMutablePointerType(SourceLoc loc, Type pointeeType) {
return getPointerType(*this, loc, pointeeType, PTK_UnsafeMutablePointer);
}
static Type getStdlibType(TypeChecker &TC, Type &cached, DeclContext *dc,
StringRef name) {
if (cached.isNull()) {
ModuleDecl *stdlib = TC.Context.getStdlibModule();
LookupTypeResult lookup = TC.lookupMemberType(dc, ModuleType::get(stdlib),
TC.Context.getIdentifier(
name));
if (lookup)
cached = lookup.back().MemberType;
}
return cached;
}
Type TypeChecker::getStringType(DeclContext *dc) {
return ::getStdlibType(*this, StringType, dc, "String");
}
Type TypeChecker::getSubstringType(DeclContext *dc) {
return ::getStdlibType(*this, SubstringType, dc, "Substring");
}
Type TypeChecker::getIntType(DeclContext *dc) {
return ::getStdlibType(*this, IntType, dc, "Int");
}
Type TypeChecker::getInt8Type(DeclContext *dc) {
return ::getStdlibType(*this, Int8Type, dc, "Int8");
}
Type TypeChecker::getUInt8Type(DeclContext *dc) {
return ::getStdlibType(*this, UInt8Type, dc, "UInt8");
}
/// Returns the maximum-sized builtin integer type.
Type TypeChecker::getMaxIntegerType(DeclContext *dc) {
if (!MaxIntegerType.isNull())
return MaxIntegerType;
SmallVector<ValueDecl *, 1> lookupResults;
getStdlibModule(dc)->lookupValue(/*AccessPath=*/{},
Context.Id_MaxBuiltinIntegerType,
NLKind::QualifiedLookup, lookupResults);
if (lookupResults.size() != 1)
return MaxIntegerType;
auto *maxIntegerTypeDecl = dyn_cast<TypeAliasDecl>(lookupResults.front());
if (!maxIntegerTypeDecl)
return MaxIntegerType;
validateDecl(maxIntegerTypeDecl);
if (!maxIntegerTypeDecl->hasInterfaceType() ||
!maxIntegerTypeDecl->getDeclaredInterfaceType()->is<BuiltinIntegerType>())
return MaxIntegerType;
MaxIntegerType = maxIntegerTypeDecl->getUnderlyingTypeLoc().getType();
return MaxIntegerType;
}
/// Find the standard type of exceptions.
///
/// We call this the "exception type" to try to avoid confusion with
/// the AST's ErrorType node.
Type TypeChecker::getExceptionType(DeclContext *dc, SourceLoc loc) {
if (NominalTypeDecl *decl = Context.getErrorDecl())
return decl->getDeclaredType();
// Not really sugar, but the actual diagnostic text is fine.
diagnose(loc, diag::sugar_type_not_found, 4);
return Type();
}
Type
TypeChecker::getDynamicBridgedThroughObjCClass(DeclContext *dc,
Type dynamicType,
Type valueType) {
// We can only bridge from class or Objective-C existential types.
if (!dynamicType->satisfiesClassConstraint())
return Type();
// If the value type cannot be bridged, we're done.
if (!valueType->isPotentiallyBridgedValueType())
return Type();
return Context.getBridgedToObjC(dc, valueType);
}
Type TypeChecker::resolveTypeInContext(
TypeDecl *typeDecl,
DeclContext *foundDC,
DeclContext *fromDC,
TypeResolutionOptions options,
bool isSpecialized,
GenericTypeResolver *resolver) {
// If we're just resolving the structure, the decl itself is all we need to
// know: return the unbound generic type.
if (options.contains(TypeResolutionFlags::ResolveStructure))
return typeDecl->getDeclaredInterfaceType();
GenericTypeToArchetypeResolver defaultResolver(fromDC);
if (!resolver)
resolver = &defaultResolver;
// If we found a generic parameter, map to the archetype if there is one.
if (auto genericParam = dyn_cast<GenericTypeParamDecl>(typeDecl)) {
return resolver->mapTypeIntoContext(
genericParam->getDeclaredInterfaceType());
}
// If we are referring to a type within its own context, and we have either
// a generic type with no generic arguments or a non-generic type, use the
// type within the context.
if (auto nominalType = dyn_cast<NominalTypeDecl>(typeDecl)) {
if (!isa<ProtocolDecl>(nominalType) &&
(!nominalType->getGenericParams() || !isSpecialized)) {
for (auto parentDC = fromDC;
!parentDC->isModuleScopeContext();
parentDC = parentDC->getParent()) {
auto *parentNominal =
parentDC->getAsNominalTypeOrNominalTypeExtensionContext();
if (parentNominal == nominalType)
return resolver->mapTypeIntoContext(
parentDC->getSelfInterfaceType());
if (isa<ExtensionDecl>(parentDC)) {
auto *extendedType = parentNominal;
while (extendedType != nullptr) {
if (extendedType == nominalType)
return resolver->mapTypeIntoContext(
extendedType->getDeclaredInterfaceType());
extendedType = extendedType->getParent()
->getAsNominalTypeOrNominalTypeExtensionContext();
}
}
}
}
}
// Simple case -- the type is not nested inside of another type.
// However, it might be nested inside another generic context, so
// we do want to write the type in terms of interface types or
// context archetypes, depending on the resolver given to us.
if (!typeDecl->getDeclContext()->isTypeContext()) {
if (auto *aliasDecl = dyn_cast<TypeAliasDecl>(typeDecl)) {
// For a generic typealias, return the unbound generic form of the type.
if (aliasDecl->getGenericParams())
return aliasDecl->getUnboundGenericType();
// Otherwise, simply return the underlying type.
return resolver->mapTypeIntoContext(
aliasDecl->getDeclaredInterfaceType());
}
// When a nominal type used outside its context, return the unbound
// generic form of the type.
if (auto *nominalDecl = dyn_cast<NominalTypeDecl>(typeDecl))
return nominalDecl->getDeclaredType();
assert(isa<ModuleDecl>(typeDecl));
return typeDecl->getDeclaredInterfaceType();
}
assert(foundDC);
// selfType is the self type of the context, unless the
// context is a protocol type, in which case we might have
// to use the existential type or superclass bound as a
// parent type instead.
Type selfType;
if (isa<NominalTypeDecl>(typeDecl) &&
typeDecl->getDeclContext()->getAsProtocolOrProtocolExtensionContext()) {
// When looking up a nominal type declaration inside of a
// protocol extension, always use the nominal type and
// not the protocol 'Self' type.
if (!foundDC->getDeclaredInterfaceType())
return ErrorType::get(Context);
selfType = resolver->mapTypeIntoContext(
foundDC->getDeclaredInterfaceType());
} else {
// Otherwise, we want the protocol 'Self' type for
// substituting into alias types and associated types.
selfType = resolver->mapTypeIntoContext(
foundDC->getSelfInterfaceType());
if (selfType->is<GenericTypeParamType>() &&
typeDecl->getDeclContext()->getAsClassOrClassExtensionContext()) {
// We found a member of a class from a protocol or protocol
// extension.
//
// Get the superclass of the 'Self' type parameter.
auto *sig = foundDC->getGenericSignatureOfContext();
auto superclassType = sig->getSuperclassBound(selfType);
assert(superclassType);
selfType = superclassType;
}
}
// Finally, substitute the base type into the member type.
return substMemberTypeWithBase(fromDC->getParentModule(), typeDecl,
selfType, resolver->usesArchetypes());
}
static TypeResolutionOptions
adjustOptionsForGenericArgs(TypeResolutionOptions options) {
options -= TypeResolutionFlags::SILType;
options -= TypeResolutionFlags::FunctionInput;
options -= TypeResolutionFlags::TypeAliasUnderlyingType;
options -= TypeResolutionFlags::AllowUnavailableProtocol;
options -= TypeResolutionFlags::AllowIUO;
return options;
}
/// This function checks if a bound generic type is UnsafePointer<Void> or
/// UnsafeMutablePointer<Void>. For these two type representations, we should
/// warn users that they are deprecated and replace them with more handy
/// UnsafeRawPointer and UnsafeMutableRawPointer, respectively.
static bool isPointerToVoid(ASTContext &Ctx, Type Ty, bool &IsMutable) {
if (Ty.isNull())
return false;
auto *BGT = Ty->getAs<BoundGenericType>();
if (!BGT)
return false;
if (BGT->getDecl() != Ctx.getUnsafePointerDecl() &&
BGT->getDecl() != Ctx.getUnsafeMutablePointerDecl())
return false;
IsMutable = BGT->getDecl() == Ctx.getUnsafeMutablePointerDecl();
assert(BGT->getGenericArgs().size() == 1);
return BGT->getGenericArgs().front()->isVoid();
}
Type TypeChecker::applyGenericArguments(Type type,
SourceLoc loc, DeclContext *dc,
GenericIdentTypeRepr *generic,
TypeResolutionOptions options,
GenericTypeResolver *resolver) {
assert(!options.contains(TypeResolutionFlags::ResolveStructure) &&
"should not touch generic arguments when resolving structure");
if (type->hasError()) {
generic->setInvalid();
return type;
}
// We must either have an unbound generic type, or a generic type alias.
if (!type->is<UnboundGenericType>()) {
auto diag = diagnose(loc, diag::not_a_generic_type, type);
// Don't add fixit on module type; that isn't the right type regardless
// of whether it had generic arguments.
if (!type->is<ModuleType>()) {
// When turning a SourceRange into CharSourceRange the closing angle
// brackets on nested generics are lexed as one token.
SourceRange angles = generic->getAngleBrackets();
diag.fixItRemoveChars(angles.Start,
angles.End.getAdvancedLocOrInvalid(1));
}
generic->setInvalid();
return type;
}
auto *unboundType = type->castTo<UnboundGenericType>();
auto *decl = unboundType->getDecl();
// Make sure we have the right number of generic arguments.
// FIXME: If we have fewer arguments than we need, that might be okay, if
// we're allowed to deduce the remaining arguments from context.
auto genericDecl = cast<GenericTypeDecl>(decl);
auto genericArgs = generic->getGenericArgs();
auto genericParams = genericDecl->getGenericParams();
if (genericParams->size() != genericArgs.size()) {
diagnose(loc, diag::type_parameter_count_mismatch, decl->getName(),
genericParams->size(), genericArgs.size(),
genericArgs.size() < genericParams->size())
.highlight(generic->getAngleBrackets());
diagnose(decl, diag::kind_identifier_declared_here,
DescriptiveDeclKind::GenericType, decl->getName());
return ErrorType::get(Context);
}
// In SIL mode, Optional<T> interprets T as a SIL type.
if (options.contains(TypeResolutionFlags::SILType)) {
if (auto nominal = dyn_cast<NominalTypeDecl>(decl)) {
if (nominal->isOptionalDecl()) {
// Validate the generic argument.
TypeLoc arg = genericArgs[0];
if (validateType(arg, dc, withoutContext(options, true), resolver))
return nullptr;
Type objectType = arg.getType();
if (!objectType)
return nullptr;
return BoundGenericType::get(nominal, /*parent*/ Type(), objectType);
}
}
}
// Cannot extend a bound generic type.
if (options.contains(TypeResolutionFlags::ExtensionBinding)) {
diagnose(loc, diag::extension_specialization,
genericDecl->getName())
.highlight(generic->getSourceRange());
return ErrorType::get(Context);
}
// FIXME: More principled handling of circularity.
if (!genericDecl->hasValidSignature()) {
diagnose(loc, diag::recursive_type_reference,
genericDecl->getDescriptiveKind(), genericDecl->getName());
diagnose(genericDecl, diag::kind_declared_here,
DescriptiveDeclKind::Type);
return ErrorType::get(Context);
}
// Resolve the types of the generic arguments.
assert(!options.contains(TypeResolutionFlags::ResolveStructure) &&
"should not touch generic arguments when resolving structure");
options = adjustOptionsForGenericArgs(options);
SmallVector<Type, 2> args;
for (auto tyR : genericArgs) {
// Propagate failure.
TypeLoc genericArg = tyR;
if (validateType(genericArg, dc, options, resolver))
return ErrorType::get(Context);
auto substTy = genericArg.getType();
// Unsatisfied dependency case.
if (!substTy)
return nullptr;
args.push_back(substTy);
}
auto result = applyUnboundGenericArguments(unboundType, genericDecl, loc,
dc, args, resolver);
if (!result)
return result;
// Migration hack.
bool isMutablePointer;
if (isPointerToVoid(dc->getASTContext(), result, isMutablePointer)) {
if (isMutablePointer)
diagnose(loc, diag::use_of_void_pointer, "Mutable").
fixItReplace(generic->getSourceRange(), "UnsafeMutableRawPointer");
else
diagnose(loc, diag::use_of_void_pointer, "").
fixItReplace(generic->getSourceRange(), "UnsafeRawPointer");
}
return result;
}
/// Apply generic arguments to the given type.
Type TypeChecker::applyUnboundGenericArguments(
UnboundGenericType *unboundType, GenericTypeDecl *decl,
SourceLoc loc, DeclContext *dc,
ArrayRef<Type> genericArgs,
GenericTypeResolver *resolver) {
assert(genericArgs.size() == decl->getGenericParams()->size() &&
"invalid arguments, use applyGenericArguments for diagnostic emitting");
// Make sure we always have a resolver to use.
GenericTypeToArchetypeResolver defaultResolver(dc);
if (!resolver)
resolver = &defaultResolver;
auto genericSig = decl->getGenericSignature();
assert(genericSig != nullptr);
TypeSubstitutionMap subs;
// Get the interface type for the declaration. We will be substituting
// type parameters that appear inside this type with the provided
// generic arguments.
auto resultType = decl->getDeclaredInterfaceType();
bool hasTypeVariable = false;
// Get the substitutions for outer generic parameters from the parent
// type.
if (auto parentType = unboundType->getParent()) {
if (parentType->hasUnboundGenericType()) {
// If we're working with a nominal type declaration, just construct
// a bound generic type without checking the generic arguments.
if (auto *nominalDecl = dyn_cast<NominalTypeDecl>(decl)) {
return BoundGenericType::get(nominalDecl, parentType, genericArgs);
}
assert(!resultType->hasTypeParameter());
return resultType;
}
subs = parentType->getContextSubstitutions(decl->getDeclContext());
hasTypeVariable |= parentType->hasTypeVariable();
}
SourceLoc noteLoc = decl->getLoc();
if (noteLoc.isInvalid())
noteLoc = loc;
// Realize the types of the generic arguments and add them to the
// substitution map.
for (unsigned i = 0, e = genericArgs.size(); i < e; i++) {
auto origTy = genericSig->getInnermostGenericParams()[i];
auto substTy = genericArgs[i];
// Enter a substitution.
subs[origTy->getCanonicalType()->castTo<GenericTypeParamType>()] =
substTy;
hasTypeVariable |= substTy->hasTypeVariable();
}
// Check the generic arguments against the requirements of the declaration's
// generic signature.
if (!hasTypeVariable) {
auto result =
checkGenericArguments(dc, loc, noteLoc, unboundType,
genericSig->getGenericParams(),
genericSig->getRequirements(),
QueryTypeSubstitutionMap{subs},
LookUpConformance(*this, dc));
switch (result) {
case RequirementCheckResult::Failure:
case RequirementCheckResult::SubstitutionFailure:
return ErrorType::get(Context);
case RequirementCheckResult::Success:
break;
}
}
// For a typealias, use the underlying type. We'll wrap up the result
// later.
auto typealias = dyn_cast<TypeAliasDecl>(decl);
if (typealias) {
resultType = typealias->getUnderlyingTypeLoc().getType();
}
// Apply the substitution map to the interface type of the declaration.
resultType = resultType.subst(QueryTypeSubstitutionMap{subs},
LookUpConformance(*this, dc),
SubstFlags::UseErrorType);
// Form a sugared typealias reference.
Type parentType = unboundType->getParent();
if (typealias && (!parentType || !parentType->isAnyExistentialType())) {
auto genericSig = typealias->getGenericSignature();
auto subMap = SubstitutionMap::get(genericSig,
QueryTypeSubstitutionMap{subs},
LookUpConformance(*this, dc));
resultType = NameAliasType::get(typealias, parentType,
subMap, resultType);
}
if (isa<NominalTypeDecl>(decl) && resultType) {
(void)useObjectiveCBridgeableConformancesOfArgs(
dc, resultType->castTo<BoundGenericType>());
}
return resultType;
}
/// \brief Diagnose a use of an unbound generic type.
static void diagnoseUnboundGenericType(TypeChecker &tc, Type ty,SourceLoc loc) {
auto unbound = ty->castTo<UnboundGenericType>();
{
InFlightDiagnostic diag = tc.diagnose(loc,
diag::generic_type_requires_arguments, ty);
if (auto *genericD = unbound->getDecl()) {
SmallString<64> genericArgsToAdd;
if (tc.getDefaultGenericArgumentsString(genericArgsToAdd, genericD))
diag.fixItInsertAfter(loc, genericArgsToAdd);
}
}
tc.diagnose(unbound->getDecl(), diag::kind_identifier_declared_here,
DescriptiveDeclKind::GenericType, unbound->getDecl()->getName());
}
// Produce a diagnostic if the type we referenced was an
// associated type but the type itself was erroneous. We'll produce a
// diagnostic here if the diagnostic for the bad type witness would show up in
// a different context.
static void maybeDiagnoseBadConformanceRef(TypeChecker &tc,
DeclContext *dc,
Type parentTy,
SourceLoc loc,
AssociatedTypeDecl *assocType) {
// If we weren't given a conformance, go look it up.
ProtocolConformance *conformance = nullptr;
if (auto conformanceRef = tc.conformsToProtocol(
parentTy, assocType->getProtocol(), dc,
(ConformanceCheckFlags::InExpression |
ConformanceCheckFlags::SuppressDependencyTracking |
ConformanceCheckFlags::AllowUnavailableConditionalRequirements))) {
if (conformanceRef->isConcrete())
conformance = conformanceRef->getConcrete();
}
// If any errors have occurred, don't bother diagnosing this cross-file
// issue.
if (tc.Context.Diags.hadAnyError())
return;
auto diagCode =
(conformance && !conformance->getConditionalRequirementsIfAvailable())
? diag::unsupported_recursion_in_associated_type_reference
: diag::broken_associated_type_witness;
tc.diagnose(loc, diagCode, assocType->getFullName(), parentTy);
}
/// \brief Returns a valid type or ErrorType in case of an error.
static Type resolveTypeDecl(TypeChecker &TC, TypeDecl *typeDecl, SourceLoc loc,
DeclContext *foundDC,
DeclContext *fromDC,
GenericIdentTypeRepr *generic,
TypeResolutionOptions options,
GenericTypeResolver *resolver) {
assert(fromDC && "No declaration context for type resolution?");
// Don't validate nominal type declarations during extension binding.
if (!options.contains(TypeResolutionFlags::ExtensionBinding) ||
!isa<NominalTypeDecl>(typeDecl)) {
// Validate the declaration.
TC.validateDeclForNameLookup(typeDecl);
// If we were not able to validate recursively, bail out.
if (!typeDecl->hasInterfaceType()) {
TC.diagnose(loc, diag::recursive_type_reference,
typeDecl->getDescriptiveKind(), typeDecl->getName());
TC.diagnose(typeDecl->getLoc(), diag::kind_declared_here,
DescriptiveDeclKind::Type);
return ErrorType::get(TC.Context);
}
}
// Resolve the type declaration to a specific type. How this occurs
// depends on the current context and where the type was found.
Type type =
TC.resolveTypeInContext(typeDecl, foundDC, fromDC, options,
generic, resolver);
if (type->is<UnboundGenericType>() && !generic &&
!options.contains(TypeResolutionFlags::AllowUnboundGenerics) &&
!options.contains(TypeResolutionFlags::TypeAliasUnderlyingType) &&
!options.contains(TypeResolutionFlags::ResolveStructure)) {
diagnoseUnboundGenericType(TC, type, loc);
return ErrorType::get(TC.Context);
}
if (type->hasError() && isa<AssociatedTypeDecl>(typeDecl)) {
maybeDiagnoseBadConformanceRef(TC, fromDC,
foundDC->getDeclaredInterfaceType(),
loc, cast<AssociatedTypeDecl>(typeDecl));
}
if (generic && !options.contains(TypeResolutionFlags::ResolveStructure)) {
// Apply the generic arguments to the type.
type = TC.applyGenericArguments(type, loc, fromDC, generic,
options, resolver);
if (!type)
return nullptr;
}
assert(type);
return type;
}
static std::string getDeclNameFromContext(DeclContext *dc,
NominalTypeDecl *nominal) {
// We don't allow an unqualified reference to a type inside an
// extension if the type is itself nested inside another type,
// eg:
//
// extension A.B { ... B ... }
//
// Instead, you must write 'A.B'. Calculate the right name to use
// for fixits.
if (!isa<ExtensionDecl>(dc)) {
SmallVector<Identifier, 2> idents;
auto *parentNominal = nominal;
while (parentNominal != nullptr) {
idents.push_back(parentNominal->getName());
parentNominal = parentNominal->getDeclContext()
->getAsNominalTypeOrNominalTypeExtensionContext();
}
std::reverse(idents.begin(), idents.end());
std::string result;
for (auto ident : idents) {
if (!result.empty())
result += ".";
result += ident.str();
}
return result;
} else {
return nominal->getName().str();
}
}
/// Diagnose a reference to an unknown type.
///
/// This routine diagnoses a reference to an unknown type, and
/// attempts to fix the reference via various means.
///
/// \param tc The type checker through which we should emit the diagnostic.
/// \param dc The context in which name lookup occurred.
///
/// \returns either the corrected type, if possible, or an error type to
/// that correction failed.
static Type diagnoseUnknownType(TypeChecker &tc, DeclContext *dc,
Type parentType,
SourceRange parentRange,
ComponentIdentTypeRepr *comp,
TypeResolutionOptions options,
NameLookupOptions lookupOptions,
GenericTypeResolver *resolver) {
// Unqualified lookup case.
if (parentType.isNull()) {
if (comp->getIdentifier() == tc.Context.Id_Self &&
!isa<GenericIdentTypeRepr>(comp)) {
DeclContext *nominalDC = nullptr;
NominalTypeDecl *nominal = nullptr;
if ((nominalDC = dc->getInnermostTypeContext()) &&
(nominal = nominalDC->getAsNominalTypeOrNominalTypeExtensionContext())) {
// Attempt to refer to 'Self' within a non-protocol nominal
// type. Fix this by replacing 'Self' with the nominal type name.
assert(!isa<ProtocolDecl>(nominal) && "Cannot be a protocol");
// Produce a Fix-It replacing 'Self' with the nominal type name.
auto name = getDeclNameFromContext(dc, nominal);
tc.diagnose(comp->getIdLoc(), diag::self_in_nominal, name)
.fixItReplace(comp->getIdLoc(), name);
// If this is a requirement, replacing 'Self' with a valid type will
// result in additional unnecessary diagnostics (does not refer to a
// generic parameter or associated type). Simply return an error type.
if (options.contains(TypeResolutionFlags::GenericRequirement))
return ErrorType::get(tc.Context);
auto type = resolver->mapTypeIntoContext(
dc->getInnermostTypeContext()->getSelfInterfaceType());
comp->overwriteIdentifier(nominal->getName());
comp->setValue(nominal, nominalDC->getParent());
return type;
}
// Attempt to refer to 'Self' from a free function.
tc.diagnose(comp->getIdLoc(), diag::dynamic_self_non_method,
dc->getParent()->isLocalContext());
return ErrorType::get(tc.Context);
}
// Try ignoring access control.
DeclContext *lookupDC = dc;
if (options.contains(TypeResolutionFlags::GenericSignature))
lookupDC = dc->getParentForLookup();
NameLookupOptions relookupOptions = lookupOptions;
relookupOptions |= NameLookupFlags::KnownPrivate;
relookupOptions |= NameLookupFlags::IgnoreAccessControl;
auto inaccessibleResults =
tc.lookupUnqualifiedType(lookupDC, comp->getIdentifier(), comp->getIdLoc(),
relookupOptions);
if (!inaccessibleResults.empty()) {
// FIXME: What if the unviable candidates have different levels of access?
auto first = cast<TypeDecl>(inaccessibleResults.front().getValueDecl());
tc.diagnose(comp->getIdLoc(), diag::candidate_inaccessible,
comp->getIdentifier(), first->getFormalAccess());
// FIXME: If any of the candidates (usually just one) are in the same
// module we could offer a fix-it.
for (auto lookupResult : inaccessibleResults)
tc.diagnose(lookupResult.getValueDecl(), diag::kind_declared_here,
DescriptiveDeclKind::Type);
// Don't try to recover here; we'll get more access-related diagnostics
// downstream if we do.
return ErrorType::get(tc.Context);
}
// Fallback.
SourceLoc L = comp->getIdLoc();
SourceRange R = SourceRange(comp->getIdLoc());
// Check if the unknown type is in the type remappings.
auto &Remapped = tc.Context.RemappedTypes;
auto TypeName = comp->getIdentifier().str();
auto I = Remapped.find(TypeName);
if (I != Remapped.end()) {
auto RemappedTy = I->second->getString();
tc.diagnose(L, diag::use_undeclared_type_did_you_mean,
comp->getIdentifier(), RemappedTy)
.highlight(R)
.fixItReplace(R, RemappedTy);
// Replace the computed type with the suggested type.
comp->overwriteIdentifier(tc.Context.getIdentifier(RemappedTy));
// HACK: 'NSUInteger' suggests both 'UInt' and 'Int'.
if (TypeName
== tc.Context.getSwiftName(KnownFoundationEntity::NSUInteger)) {
tc.diagnose(L, diag::note_remapped_type, "UInt")
.fixItReplace(R, "UInt");
}
return I->second;
}
tc.diagnose(L, diag::use_undeclared_type,
comp->getIdentifier())
.highlight(R);
return ErrorType::get(tc.Context);
}
// Qualified lookup case.
if (!parentType->mayHaveMembers()) {
tc.diagnose(comp->getIdLoc(), diag::invalid_member_type,
comp->getIdentifier(), parentType)
.highlight(parentRange);
return ErrorType::get(tc.Context);
}
// Try ignoring access control.
NameLookupOptions relookupOptions = lookupOptions;
relookupOptions |= NameLookupFlags::KnownPrivate;
relookupOptions |= NameLookupFlags::IgnoreAccessControl;
auto inaccessibleMembers = tc.lookupMemberType(dc, parentType,
comp->getIdentifier(),
relookupOptions);
if (inaccessibleMembers) {
// FIXME: What if the unviable candidates have different levels of access?
const TypeDecl *first = inaccessibleMembers.front().Member;
tc.diagnose(comp->getIdLoc(), diag::candidate_inaccessible,
comp->getIdentifier(), first->getFormalAccess());
// FIXME: If any of the candidates (usually just one) are in the same module
// we could offer a fix-it.
for (auto lookupResult : inaccessibleMembers)
tc.diagnose(lookupResult.Member, diag::kind_declared_here,
DescriptiveDeclKind::Type);
// Don't try to recover here; we'll get more access-related diagnostics
// downstream if we do.
return ErrorType::get(tc.Context);
}
// FIXME: Typo correction!
// Lookup into a type.
if (auto moduleType = parentType->getAs<ModuleType>()) {
tc.diagnose(comp->getIdLoc(), diag::no_module_type,
comp->getIdentifier(), moduleType->getModule()->getName());
} else {
LookupResult memberLookup;
// Let's try to lookup given identifier as a member of the parent type,
// this allows for more precise diagnostic, which distinguishes between
// identifier not found as a member type vs. not found at all.
NameLookupOptions memberLookupOptions = lookupOptions;
memberLookupOptions |= NameLookupFlags::IgnoreAccessControl;
memberLookupOptions |= NameLookupFlags::KnownPrivate;
memberLookup = tc.lookupMember(dc, parentType, comp->getIdentifier(),
memberLookupOptions);
// Looks like this is not a member type, but simply a member of parent type.
if (!memberLookup.empty()) {
auto member = memberLookup[0].getValueDecl();
tc.diagnose(comp->getIdLoc(), diag::invalid_member_reference,
member->getDescriptiveKind(), comp->getIdentifier(),
parentType)
.highlight(parentRange);
} else {
tc.diagnose(comp->getIdLoc(), diag::invalid_member_type,
comp->getIdentifier(), parentType)
.highlight(parentRange);
}
}
return ErrorType::get(tc.Context);
}
static Type
resolveTopLevelIdentTypeComponent(TypeChecker &TC, DeclContext *DC,
ComponentIdentTypeRepr *comp,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver);
static Type
resolveGenericSignatureComponent(TypeChecker &TC, DeclContext *DC,
ComponentIdentTypeRepr *comp,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver) {
if (!DC->isInnermostContextGeneric())
return Type();
auto *genericParams = DC->getGenericParamsOfContext();
if (!isa<ExtensionDecl>(DC)) {
auto matchingParam =
std::find_if(genericParams->begin(), genericParams->end(),
[comp](const GenericTypeParamDecl *param) {
return param->getFullName().matchesRef(comp->getIdentifier());
});
if (matchingParam == genericParams->end())
return Type();
comp->setValue(*matchingParam, nullptr);
return resolveTopLevelIdentTypeComponent(TC, DC, comp, options,
diagnoseErrors, resolver);
}
// If we are inside an extension of a nested type, we have to visit
// all outer parameter lists. Otherwise, we will visit them when
// name lookup goes ahead and checks the outer DeclContext.
for (auto *outerParams = genericParams;
outerParams != nullptr;
outerParams = outerParams->getOuterParameters()) {
auto matchingParam =
std::find_if(outerParams->begin(), outerParams->end(),
[comp](const GenericTypeParamDecl *param) {
return param->getFullName().matchesRef(comp->getIdentifier());
});
if (matchingParam != outerParams->end()) {
comp->setValue(*matchingParam, nullptr);
return resolveTopLevelIdentTypeComponent(TC, DC, comp, options,
diagnoseErrors, resolver);
}
}
// If the lookup occurs from within a trailing 'where' clause of
// a constrained extension, also look for associated types and typealiases
// in the protocol.
if (genericParams->hasTrailingWhereClause() &&
comp->getIdLoc().isValid() &&
TC.Context.SourceMgr.rangeContainsTokenLoc(
genericParams->getTrailingWhereClauseSourceRange(),
comp->getIdLoc())) {
auto nominal = DC->getAsNominalTypeOrNominalTypeExtensionContext();
SmallVector<ValueDecl *, 4> decls;
if (DC->lookupQualified(nominal->getDeclaredInterfaceType(),
comp->getIdentifier(),
NL_OnlyTypes|NL_QualifiedDefault|NL_ProtocolMembers,
&TC,
decls)) {
for (const auto decl : decls) {
// FIXME: Better ambiguity handling.
auto typeDecl = cast<TypeDecl>(decl);
if (!isa<ProtocolDecl>(typeDecl->getDeclContext())) continue;
comp->setValue(typeDecl, DC);
return resolveTopLevelIdentTypeComponent(TC, DC, comp, options,
diagnoseErrors, resolver);
}
}
}
return Type();
}
/// Resolve the given identifier type representation as an unqualified type,
/// returning the type it references.
///
/// \returns Either the resolved type or a null type, the latter of
/// which indicates that some dependencies were unsatisfied.
static Type
resolveTopLevelIdentTypeComponent(TypeChecker &TC, DeclContext *DC,
ComponentIdentTypeRepr *comp,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver) {
// Short-circuiting.
if (comp->isInvalid()) return ErrorType::get(TC.Context);
// If the component has already been bound to a declaration, handle
// that now.
if (auto *typeDecl = comp->getBoundDecl()) {
// Resolve the type declaration within this context.
return resolveTypeDecl(TC, typeDecl, comp->getIdLoc(),
comp->getDeclContext(), DC,
dyn_cast<GenericIdentTypeRepr>(comp), options,
resolver);
}
// Resolve the first component, which is the only one that requires
// unqualified name lookup.
DeclContext *lookupDC = DC;
// Dynamic 'Self' in the result type of a function body.
if (options.contains(TypeResolutionFlags::DynamicSelfResult) &&
comp->getIdentifier() == TC.Context.Id_Self) {
auto func = cast<FuncDecl>(DC);
assert(func->hasDynamicSelf() && "Not marked as having dynamic Self?");
// FIXME: The passed-in TypeRepr should get 'typechecked' as well.
// The issue is though that ComponentIdentTypeRepr only accepts a ValueDecl
// while the 'Self' type is more than just a reference to a TypeDecl.
auto selfType = resolver->mapTypeIntoContext(
func->getDeclContext()->getSelfInterfaceType());
return DynamicSelfType::get(selfType, TC.Context);
}
// For lookups within the generic signature, look at the generic
// parameters (only), then move up to the enclosing context.
if (options.contains(TypeResolutionFlags::GenericSignature)) {
Type type = resolveGenericSignatureComponent(
TC, DC, comp, options, diagnoseErrors, resolver);
if (type)
return type;
if (!DC->isCascadingContextForLookup(/*excludeFunctions*/false))
options |= TypeResolutionFlags::KnownNonCascadingDependency;
lookupDC = DC->getParentForLookup();
}
auto id = comp->getIdentifier();
NameLookupOptions lookupOptions = defaultUnqualifiedLookupOptions;
if (options.contains(TypeResolutionFlags::KnownNonCascadingDependency))
lookupOptions |= NameLookupFlags::KnownPrivate;
auto globals = TC.lookupUnqualifiedType(lookupDC,
id,
comp->getIdLoc(),
lookupOptions);
// Process the names we found.
Type current;
TypeDecl *currentDecl = nullptr;
DeclContext *currentDC = nullptr;
bool isAmbiguous = false;
for (const auto entry : globals) {
auto *foundDC = entry.getDeclContext();
auto *typeDecl = cast<TypeDecl>(entry.getValueDecl());
Type type = resolveTypeDecl(TC, typeDecl, comp->getIdLoc(),
foundDC, DC,
dyn_cast<GenericIdentTypeRepr>(comp), options,
resolver);
if (!type)
return type;
if (type->is<ErrorType>())
return type;
// If this is the first result we found, record it.
if (current.isNull()) {
current = type;
currentDecl = typeDecl;
currentDC = foundDC;
continue;
}
// Otherwise, check for an ambiguity.
if (!resolver->areSameType(current, type)) {
isAmbiguous = true;
break;
}
// We have a found multiple type aliases that refer to the same thing.
// Ignore the duplicate.
}
// Complain about any ambiguities we detected.
// FIXME: We could recover by looking at later components.
if (isAmbiguous) {
if (diagnoseErrors) {
TC.diagnose(comp->getIdLoc(), diag::ambiguous_type_base,
comp->getIdentifier())
.highlight(comp->getIdLoc());
for (auto entry : globals) {
TC.diagnose(entry.getValueDecl(), diag::found_candidate);
}
}
comp->setInvalid();
return ErrorType::get(TC.Context);
}
// If we found nothing, complain and give ourselves a chance to recover.
if (current.isNull()) {
// If we're not allowed to complain or we couldn't fix the
// source, bail out.
if (!diagnoseErrors)
return ErrorType::get(TC.Context);
return diagnoseUnknownType(TC, DC, nullptr, SourceRange(), comp, options,
lookupOptions, resolver);
}
comp->setValue(currentDecl, currentDC);
return current;
}
/// Resolve the given identifier type representation as a qualified
/// lookup within the given parent type, returning the type it
/// references.
static Type resolveNestedIdentTypeComponent(
TypeChecker &TC, DeclContext *DC,
Type parentTy,
SourceRange parentRange,
ComponentIdentTypeRepr *comp,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver) {
auto maybeApplyGenericArgs = [&](Type memberType) {
// If there are generic arguments, apply them now.
if (!options.contains(TypeResolutionFlags::ResolveStructure)) {
if (auto genComp = dyn_cast<GenericIdentTypeRepr>(comp)) {
return TC.applyGenericArguments(memberType, comp->getIdLoc(),
DC, genComp, options, resolver);
}
}
if (memberType->is<UnboundGenericType>() &&
!options.contains(TypeResolutionFlags::AllowUnboundGenerics) &&
!options.contains(TypeResolutionFlags::TypeAliasUnderlyingType) &&
!options.contains(TypeResolutionFlags::ResolveStructure)) {
diagnoseUnboundGenericType(TC, memberType, comp->getLoc());
return ErrorType::get(TC.Context);
}
return memberType;
};
auto maybeDiagnoseBadMemberType = [&](TypeDecl *member, Type memberType,
AssociatedTypeDecl *inferredAssocType) {
// Diagnose invalid cases.
if (TC.isUnsupportedMemberTypeAccess(parentTy, member)) {
if (diagnoseErrors) {
if (parentTy->is<UnboundGenericType>())
diagnoseUnboundGenericType(TC, parentTy, parentRange.End);
else if (parentTy->isExistentialType() &&
isa<AssociatedTypeDecl>(member)) {
TC.diagnose(comp->getIdLoc(), diag::assoc_type_outside_of_protocol,
comp->getIdentifier());
} else if (parentTy->isExistentialType() &&
isa<TypeAliasDecl>(member)) {
TC.diagnose(comp->getIdLoc(), diag::typealias_outside_of_protocol,
comp->getIdentifier());
}
}
return ErrorType::get(TC.Context);
}
// Only the last component of the underlying type of a type alias may
// be an unbound generic.
if (options & TypeResolutionFlags::TypeAliasUnderlyingType) {
if (parentTy->is<UnboundGenericType>()) {
if (diagnoseErrors)
diagnoseUnboundGenericType(TC, parentTy, parentRange.End);
return ErrorType::get(TC.Context);
}
}
// Diagnose a bad conformance reference if we need to.
if (inferredAssocType && diagnoseErrors && memberType &&
memberType->hasError()) {
maybeDiagnoseBadConformanceRef(TC, DC, parentTy, comp->getLoc(),
inferredAssocType);
}
// If we found a reference to an associated type or other member type that
// was marked invalid, just return ErrorType to silence downstream errors.
if (member->isInvalid())
return ErrorType::get(TC.Context);
// At this point, we need to have resolved the type of the member.
if (!memberType || memberType->hasError())
return memberType;
// If there are generic arguments, apply them now.
return maybeApplyGenericArgs(memberType);
};
// Short-circuiting.
if (comp->isInvalid()) return ErrorType::get(TC.Context);
// If the parent is a type parameter, the member is a dependent member,
// and we skip much of the work below.
if (parentTy->isTypeParameter()) {
if (auto memberType = resolver->resolveDependentMemberType(
parentTy, DC, parentRange, comp)) {
// Hack -- if we haven't resolved this to a declaration yet, don't
// attempt to apply generic arguments, since this will emit a
// diagnostic, and its possible that this type will become a concrete
// type later on.
if (!memberType->is<DependentMemberType>() ||
memberType->castTo<DependentMemberType>()->getAssocType()) {
return maybeApplyGenericArgs(memberType);
}
return memberType;
}
}
// Phase 2: If a declaration has already been bound, use it.
if (auto *typeDecl = comp->getBoundDecl()) {
auto memberType = TC.substMemberTypeWithBase(DC->getParentModule(),
typeDecl, parentTy);
return maybeDiagnoseBadMemberType(typeDecl, memberType, nullptr);
}
// Phase 1: Find and bind the component decl.
// Look for member types with the given name.
bool isKnownNonCascading = options.contains(TypeResolutionFlags::KnownNonCascadingDependency);
if (!isKnownNonCascading && options.contains(TypeResolutionFlags::InExpression)) {
// Expressions cannot affect a function's signature.
isKnownNonCascading = isa<AbstractFunctionDecl>(DC);
}
NameLookupOptions lookupOptions = defaultMemberLookupOptions;
if (isKnownNonCascading)
lookupOptions |= NameLookupFlags::KnownPrivate;
// FIXME: Lift the restriction for TypeResolutionFlags::InheritanceClause
if (options.contains(TypeResolutionFlags::ExtensionBinding) ||
options.contains(TypeResolutionFlags::InheritanceClause))
lookupOptions -= NameLookupFlags::ProtocolMembers;
LookupTypeResult memberTypes;
if (parentTy->mayHaveMembers())
memberTypes = TC.lookupMemberType(DC, parentTy, comp->getIdentifier(),
lookupOptions);
// Name lookup was ambiguous. Complain.
// FIXME: Could try to apply generic arguments first, and see whether
// that resolves things. But do we really want that to succeed?
if (memberTypes.size() > 1) {
if (diagnoseErrors)
TC.diagnoseAmbiguousMemberType(parentTy, parentRange,
comp->getIdentifier(), comp->getIdLoc(),
memberTypes);
return ErrorType::get(TC.Context);
}
// If we didn't find anything, complain.
Type memberType;
TypeDecl *member = nullptr;
AssociatedTypeDecl *inferredAssocType = nullptr;
if (!memberTypes) {
// If we're not allowed to complain or we couldn't fix the
// source, bail out.
if (!diagnoseErrors)
return ErrorType::get(TC.Context);
memberType = diagnoseUnknownType(TC, DC, parentTy, parentRange, comp,
options, lookupOptions, resolver);
member = comp->getBoundDecl();
if (!member)
return ErrorType::get(TC.Context);
} else {
memberType = memberTypes.back().MemberType;
member = memberTypes.back().Member;
inferredAssocType = memberTypes.back().InferredAssociatedType;
comp->setValue(member, nullptr);
}
return maybeDiagnoseBadMemberType(member, memberType, inferredAssocType);
}
static Type resolveIdentTypeComponent(
TypeChecker &TC, DeclContext *DC,
ArrayRef<ComponentIdentTypeRepr *> components,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver) {
auto comp = components.back();
// The first component uses unqualified lookup.
auto parentComps = components.slice(0, components.size()-1);
if (parentComps.empty()) {
return resolveTopLevelIdentTypeComponent(TC, DC, comp, options,
diagnoseErrors, resolver);
}
// All remaining components use qualified lookup.
// Resolve the parent type.
Type parentTy = resolveIdentTypeComponent(TC, DC, parentComps, options,
diagnoseErrors, resolver);
if (!parentTy || parentTy->hasError()) return parentTy;
SourceRange parentRange(parentComps.front()->getIdLoc(),
parentComps.back()->getSourceRange().End);
// Resolve the nested type.
return resolveNestedIdentTypeComponent(TC, DC, parentTy,
parentRange, comp,
options, diagnoseErrors,
resolver);
}
static bool diagnoseAvailability(IdentTypeRepr *IdType,
DeclContext *DC, TypeChecker &TC,
bool AllowPotentiallyUnavailableProtocol) {
auto componentRange = IdType->getComponentRange();
for (auto comp : componentRange) {
if (auto *typeDecl = comp->getBoundDecl()) {
// In Swift 3, components other than the last one were not properly
// checked for availability.
// FIXME: We should try to downgrade these errors to warnings, not just
// skip diagnosing them.
if (TC.getLangOpts().isSwiftVersion3() && comp != componentRange.back())
continue;
if (diagnoseDeclAvailability(typeDecl, TC, DC, comp->getIdLoc(),
AllowPotentiallyUnavailableProtocol,
/*SignalOnPotentialUnavailability*/false)) {
return true;
}
}
}
return false;
}
// Hack to apply context-specific @escaping to an AST function type.
static Type applyNonEscapingFromContext(DeclContext *DC,
Type ty,
TypeResolutionOptions options) {
// Remember whether this is a function parameter.
bool defaultNoEscape =
!options.contains(TypeResolutionFlags::EnumCase) &&
options.contains(TypeResolutionFlags::FunctionInput);
// Desugar here
auto *funcTy = ty->castTo<FunctionType>();
auto extInfo = funcTy->getExtInfo();
if (defaultNoEscape && !extInfo.isNoEscape()) {
extInfo = extInfo.withNoEscape();
// We lost the sugar to flip the isNoEscape bit.
//
// FIXME: It would be better to add a new AttributedType sugared type,
// which would wrap the NameAliasType or ParenType, and apply the
// isNoEscape bit when de-sugaring.
// <https://bugs.swift.org/browse/SR-2520>
return FunctionType::get(funcTy->getParams(), funcTy->getResult(), extInfo);
}
// Note: original sugared type
return ty;
}
/// \brief Returns a valid type or ErrorType in case of an error.
Type TypeChecker::resolveIdentifierType(
DeclContext *DC,
IdentTypeRepr *IdType,
TypeResolutionOptions options,
bool diagnoseErrors,
GenericTypeResolver *resolver) {
assert(resolver && "Missing generic type resolver");
auto ComponentRange = IdType->getComponentRange();
auto Components = llvm::makeArrayRef(ComponentRange.begin(),
ComponentRange.end());
Type result = resolveIdentTypeComponent(*this, DC, Components, options,
diagnoseErrors, resolver);
if (!result) return nullptr;
if (auto moduleTy = result->getAs<ModuleType>()) {
if (diagnoseErrors) {
auto moduleName = moduleTy->getModule()->getName();
diagnose(Components.back()->getIdLoc(),
diag::use_undeclared_type, moduleName);
diagnose(Components.back()->getIdLoc(),
diag::note_module_as_type, moduleName);
}
Components.back()->setInvalid();
return ErrorType::get(Context);
}
// Hack to apply context-specific @escaping to a typealias with an underlying
// function type.
if (result->is<FunctionType>())
result = applyNonEscapingFromContext(DC, result, options);
// Check the availability of the type.
// We allow a type to conform to a protocol that is less available than
// the type itself. This enables a type to retroactively model or directly
// conform to a protocol only available on newer OSes and yet still be used on
// older OSes.
// To support this, inside inheritance clauses we allow references to
// protocols that are unavailable in the current type refinement context.
if (!(options & TypeResolutionFlags::AllowUnavailable) &&
diagnoseAvailability(IdType, DC, *this,
options.contains(TypeResolutionFlags::AllowUnavailableProtocol))) {
Components.back()->setInvalid();
return ErrorType::get(Context);
}
return result;
}
bool TypeChecker::validateType(TypeLoc &Loc, DeclContext *DC,
TypeResolutionOptions options,
GenericTypeResolver *resolver) {
// FIXME: Verify that these aren't circular and infinite size.
assert(!options.contains(TypeResolutionFlags::ResolveStructure) &&
"ResolveStructure does not do full validation");
// If we've already validated this type, don't do so again.
if (Loc.wasValidated())
return Loc.isError();
if (Context.Stats)
Context.Stats->getFrontendCounters().NumTypesValidated++;
Type type = Loc.getType();
if (type.isNull()) {
type = resolveType(Loc.getTypeRepr(), DC, options, resolver);
if (!type) {
type = ErrorType::get(Context);
// Diagnose types that are illegal in SIL.
} else if (options.contains(TypeResolutionFlags::SILType)
&& !type->isLegalSILType()) {
diagnose(Loc.getLoc(), diag::illegal_sil_type, type);
Loc.setInvalidType(Context);
return true;
}
}
Loc.setType(type);
return type->hasError();
}
namespace {
const auto DefaultParameterConvention = ParameterConvention::Direct_Unowned;
const auto DefaultResultConvention = ResultConvention::Unowned;
class TypeResolver {
TypeChecker &TC;
ASTContext &Context;
DeclContext *DC;
GenericTypeResolver *Resolver;
public:
TypeResolver(TypeChecker &tc, DeclContext *DC,
GenericTypeResolver *resolver)
: TC(tc), Context(tc.Context), DC(DC), Resolver(resolver)
{
assert(resolver);
}
Type resolveType(TypeRepr *repr, TypeResolutionOptions options);
private:
Type resolveAttributedType(AttributedTypeRepr *repr,
TypeResolutionOptions options);
Type resolveAttributedType(TypeAttributes &attrs, TypeRepr *repr,
TypeResolutionOptions options);
Type resolveASTFunctionType(FunctionTypeRepr *repr,
TypeResolutionOptions options,
FunctionType::ExtInfo extInfo
= FunctionType::ExtInfo());
bool
resolveASTFunctionTypeParams(TupleTypeRepr *inputRepr,
TypeResolutionOptions options,
bool requiresMappingOut,
SmallVectorImpl<AnyFunctionType::Param> &ps);
Type resolveSILFunctionType(FunctionTypeRepr *repr,
TypeResolutionOptions options,
SILCoroutineKind coroutineKind
= SILCoroutineKind::None,
SILFunctionType::ExtInfo extInfo
= SILFunctionType::ExtInfo(),
ParameterConvention calleeConvention
= DefaultParameterConvention,
TypeRepr *witnessmethodProtocol = nullptr);
SILParameterInfo resolveSILParameter(TypeRepr *repr,
TypeResolutionOptions options);
SILYieldInfo resolveSILYield(TypeAttributes &remainingAttrs,
TypeRepr *repr, TypeResolutionOptions options);
bool resolveSILResults(TypeRepr *repr, TypeResolutionOptions options,
SmallVectorImpl<SILYieldInfo> &yields,
SmallVectorImpl<SILResultInfo> &results,
Optional<SILResultInfo> &errorResult);
bool resolveSingleSILResult(TypeRepr *repr, TypeResolutionOptions options,
SmallVectorImpl<SILYieldInfo> &yields,
SmallVectorImpl<SILResultInfo> &results,
Optional<SILResultInfo> &errorResult);
Type resolveSpecifierTypeRepr(SpecifierTypeRepr *repr,
TypeResolutionOptions options);
Type resolveArrayType(ArrayTypeRepr *repr,
TypeResolutionOptions options);
Type resolveDictionaryType(DictionaryTypeRepr *repr,
TypeResolutionOptions options);
Type resolveOptionalType(OptionalTypeRepr *repr,
TypeResolutionOptions options);
Type resolveImplicitlyUnwrappedOptionalType(ImplicitlyUnwrappedOptionalTypeRepr *repr,
TypeResolutionOptions options);
Type resolveTupleType(TupleTypeRepr *repr,
TypeResolutionOptions options);
Type resolveCompositionType(CompositionTypeRepr *repr,
TypeResolutionOptions options);
Type resolveMetatypeType(MetatypeTypeRepr *repr,
TypeResolutionOptions options);
Type resolveProtocolType(ProtocolTypeRepr *repr,
TypeResolutionOptions options);
Type resolveSILBoxType(SILBoxTypeRepr *repr,
TypeResolutionOptions options);
Type buildMetatypeType(MetatypeTypeRepr *repr,
Type instanceType,
Optional<MetatypeRepresentation> storedRepr);
Type buildProtocolType(ProtocolTypeRepr *repr,
Type instanceType,
Optional<MetatypeRepresentation> storedRepr);
};
} // end anonymous namespace
Type TypeChecker::resolveType(TypeRepr *TyR, DeclContext *DC,
TypeResolutionOptions options,
GenericTypeResolver *resolver) {
PrettyStackTraceTypeRepr stackTrace(Context, "resolving", TyR);
// Make sure we always have a resolver to use.
GenericTypeToArchetypeResolver defaultResolver(DC);
if (!resolver)
resolver = &defaultResolver;
TypeResolver typeResolver(*this, DC, resolver);
auto result = typeResolver.resolveType(TyR, options);
// If we resolved down to an error, make sure to mark the typeRepr as invalid
// so we don't produce a redundant diagnostic.
if (result && result->hasError())
TyR->setInvalid();
return result;
}
Type TypeResolver::resolveType(TypeRepr *repr, TypeResolutionOptions options) {
assert(repr && "Cannot validate null TypeReprs!");
// If we know the type representation is invalid, just return an
// error type.
if (repr->isInvalid()) return ErrorType::get(TC.Context);
// Strip the "is function input" bits unless this is a type that knows about
// them.
if (!isa<SpecifierTypeRepr>(repr) && !isa<TupleTypeRepr>(repr) &&
!isa<AttributedTypeRepr>(repr) && !isa<FunctionTypeRepr>(repr) &&
!isa<IdentTypeRepr>(repr)) {
options -= TypeResolutionFlags::FunctionInput;
options -= TypeResolutionFlags::TypeAliasUnderlyingType;
}
if (Context.LangOpts.DisableAvailabilityChecking)
options |= TypeResolutionFlags::AllowUnavailable;
switch (repr->getKind()) {
case TypeReprKind::Error:
return ErrorType::get(Context);
case TypeReprKind::Attributed:
return resolveAttributedType(cast<AttributedTypeRepr>(repr), options);
case TypeReprKind::InOut:
case TypeReprKind::Shared:
case TypeReprKind::Owned:
return resolveSpecifierTypeRepr(cast<SpecifierTypeRepr>(repr), options);
case TypeReprKind::SimpleIdent:
case TypeReprKind::GenericIdent:
case TypeReprKind::CompoundIdent:
return TC.resolveIdentifierType(DC, cast<IdentTypeRepr>(repr), options,
/*diagnoseErrors*/ true, Resolver);
case TypeReprKind::Function: {
if (!(options & TypeResolutionFlags::SILType)) {
// Default non-escaping for closure parameters
auto result =
resolveASTFunctionType(cast<FunctionTypeRepr>(repr), options);
if (result && result->is<FunctionType>())
return applyNonEscapingFromContext(DC, result, options);
return result;
}
return resolveSILFunctionType(cast<FunctionTypeRepr>(repr), options);
}
case TypeReprKind::SILBox:
assert((options & TypeResolutionFlags::SILType) && "SILBox repr in non-SIL type context?!");
return resolveSILBoxType(cast<SILBoxTypeRepr>(repr), options);
case TypeReprKind::Array:
return resolveArrayType(cast<ArrayTypeRepr>(repr), options);
case TypeReprKind::Dictionary:
return resolveDictionaryType(cast<DictionaryTypeRepr>(repr), options);
case TypeReprKind::Optional:
return resolveOptionalType(cast<OptionalTypeRepr>(repr), options);
case TypeReprKind::ImplicitlyUnwrappedOptional:
return resolveImplicitlyUnwrappedOptionalType(
cast<ImplicitlyUnwrappedOptionalTypeRepr>(repr),
options);
case TypeReprKind::Tuple:
return resolveTupleType(cast<TupleTypeRepr>(repr), options);
case TypeReprKind::Composition:
return resolveCompositionType(cast<CompositionTypeRepr>(repr), options);
case TypeReprKind::Metatype:
return resolveMetatypeType(cast<MetatypeTypeRepr>(repr), options);
case TypeReprKind::Protocol:
return resolveProtocolType(cast<ProtocolTypeRepr>(repr), options);
case TypeReprKind::Fixed:
return cast<FixedTypeRepr>(repr)->getType();
}
llvm_unreachable("all cases should be handled");
}
static Type rebuildWithDynamicSelf(ASTContext &Context, Type ty) {
if (auto metatypeTy = ty->getAs<MetatypeType>()) {
return MetatypeType::get(
rebuildWithDynamicSelf(Context, metatypeTy->getInstanceType()),
metatypeTy->getRepresentation());
} else if (auto optionalTy = ty->getOptionalObjectType()) {
return OptionalType::get(rebuildWithDynamicSelf(Context, optionalTy));
} else {
return DynamicSelfType::get(ty, Context);
}
}
Type TypeResolver::resolveAttributedType(AttributedTypeRepr *repr,
TypeResolutionOptions options) {
// Copy the attributes, since we're about to start hacking on them.
TypeAttributes attrs = repr->getAttrs();
assert(!attrs.empty());
return resolveAttributedType(attrs, repr->getTypeRepr(), options);
}
Type TypeResolver::resolveAttributedType(TypeAttributes &attrs,
TypeRepr *repr,
TypeResolutionOptions options) {
// Convenience to grab the source range of a type attribute.
auto getTypeAttrRangeWithAt = [](TypeChecker &TC, SourceLoc attrLoc) {
return SourceRange(attrLoc.getAdvancedLoc(-1),
Lexer::getLocForEndOfToken(TC.Context.SourceMgr,
attrLoc));
};
// Remember whether this is a function parameter.
bool isParam = options.contains(TypeResolutionFlags::FunctionInput);
bool isVariadicFunctionParam =
!options.contains(TypeResolutionFlags::EnumCase) &&
options.contains(TypeResolutionFlags::VariadicFunctionInput);
// The type we're working with, in case we want to build it differently
// based on the attributes we see.
Type ty;
// In SIL *only*, allow @thin, @thick, or @objc_metatype to apply to
// a metatype.
if (attrs.has(TAK_thin) || attrs.has(TAK_thick) ||
attrs.has(TAK_objc_metatype)) {
if (auto SF = DC->getParentSourceFile()) {
if (SF->Kind == SourceFileKind::SIL) {
TypeRepr *base;
if (auto metatypeRepr = dyn_cast<MetatypeTypeRepr>(repr)) {
base = metatypeRepr->getBase();
} else if (auto protocolRepr = dyn_cast<ProtocolTypeRepr>(repr)) {
base = protocolRepr->getBase();
} else {
base = nullptr;
}
if (base) {
Optional<MetatypeRepresentation> storedRepr;
// The instance type is not a SIL type.
auto instanceOptions = options;
instanceOptions -= TypeResolutionFlags::SILType;
instanceOptions -= TypeResolutionFlags::FunctionInput;
instanceOptions -= TypeResolutionFlags::TypeAliasUnderlyingType;
auto instanceTy = resolveType(base, instanceOptions);
if (!instanceTy || instanceTy->hasError())
return instanceTy;
// Check for @thin.
if (attrs.has(TAK_thin)) {
storedRepr = MetatypeRepresentation::Thin;
attrs.clearAttribute(TAK_thin);
}
// Check for @thick.
if (attrs.has(TAK_thick)) {
if (storedRepr)
TC.diagnose(repr->getStartLoc(),
diag::sil_metatype_multiple_reprs);
storedRepr = MetatypeRepresentation::Thick;
attrs.clearAttribute(TAK_thick);
}
// Check for @objc_metatype.
if (attrs.has(TAK_objc_metatype)) {
if (storedRepr)
TC.diagnose(repr->getStartLoc(),
diag::sil_metatype_multiple_reprs);
storedRepr = MetatypeRepresentation::ObjC;
attrs.clearAttribute(TAK_objc_metatype);
}
if (instanceTy->hasError()) {
ty = instanceTy;
} else if (auto metatype = dyn_cast<MetatypeTypeRepr>(repr)) {
ty = buildMetatypeType(metatype, instanceTy, storedRepr);
} else {
ty = buildProtocolType(cast<ProtocolTypeRepr>(repr),
instanceTy, storedRepr);
}
}
}
}
}
// Pass down the variable function type attributes to the
// function-type creator.
static const TypeAttrKind FunctionAttrs[] = {
TAK_convention, TAK_noreturn, TAK_pseudogeneric,
TAK_callee_owned, TAK_callee_guaranteed, TAK_noescape, TAK_autoclosure,
TAK_escaping, TAK_yield_once, TAK_yield_many
};
auto checkUnsupportedAttr = [&](TypeAttrKind attr) {
if (attrs.has(attr)) {
TC.diagnose(attrs.getLoc(attr), diag::attribute_not_supported);
attrs.clearAttribute(attr);
}
};
// Some function representation attributes are not supported at source level;
// only SIL knows how to handle them. Reject them unless this is a SIL input.
if (!(options & TypeResolutionFlags::SILType)) {
for (auto silOnlyAttr : {TAK_callee_owned, TAK_callee_guaranteed}) {
checkUnsupportedAttr(silOnlyAttr);
}
}
// Other function representation attributes are not normally supported at
// source level, but we want to support them there in SIL files.
auto SF = DC->getParentSourceFile();
if (!SF || SF->Kind != SourceFileKind::SIL) {
for (auto silOnlyAttr : {TAK_thin, TAK_thick}) {
checkUnsupportedAttr(silOnlyAttr);
}
}
bool hasFunctionAttr = false;
for (auto i : FunctionAttrs)
if (attrs.has(i)) {
hasFunctionAttr = true;
break;
}
// Function attributes require a syntactic function type.
auto *fnRepr = dyn_cast<FunctionTypeRepr>(repr);
if (!fnRepr) {
if (attrs.has(TAK_autoclosure)) {
TC.diagnose(attrs.getLoc(TAK_autoclosure),
diag::autoclosure_function_type);
attrs.clearAttribute(TAK_autoclosure);
}
// Fall through to diagnose below.
} else if (hasFunctionAttr && (options & TypeResolutionFlags::SILType)) {
SILFunctionType::Representation rep;
TypeRepr *witnessMethodProtocol = nullptr;
auto coroutineKind = SILCoroutineKind::None;
if (attrs.has(TAK_yield_once)) {
coroutineKind = SILCoroutineKind::YieldOnce;
} else if (attrs.has(TAK_yield_many)) {
coroutineKind = SILCoroutineKind::YieldMany;
}
auto calleeConvention = ParameterConvention::Direct_Unowned;
if (attrs.has(TAK_callee_owned)) {
if (attrs.has(TAK_callee_guaranteed)) {
TC.diagnose(attrs.getLoc(TAK_callee_owned),
diag::sil_function_repeat_convention, /*callee*/ 2);
}
calleeConvention = ParameterConvention::Direct_Owned;
} else if (attrs.has(TAK_callee_guaranteed)) {
calleeConvention = ParameterConvention::Direct_Guaranteed;
}
if (!attrs.hasConvention()) {
rep = SILFunctionType::Representation::Thick;
} else {
auto convention = attrs.getConvention();
// SIL exposes a greater number of conventions than Swift source.
auto parsedRep =
llvm::StringSwitch<Optional<SILFunctionType::Representation>>(
convention)
.Case("thick", SILFunctionType::Representation::Thick)
.Case("block", SILFunctionType::Representation::Block)
.Case("thin", SILFunctionType::Representation::Thin)
.Case("c", SILFunctionType::Representation::CFunctionPointer)
.Case("method", SILFunctionType::Representation::Method)
.Case("objc_method", SILFunctionType::Representation::ObjCMethod)
.Case("witness_method",
SILFunctionType::Representation::WitnessMethod)
.Default(None);
if (!parsedRep) {
TC.diagnose(attrs.getLoc(TAK_convention),
diag::unsupported_sil_convention, attrs.getConvention());
rep = SILFunctionType::Representation::Thin;
} else {
rep = *parsedRep;
}
if (rep == SILFunctionType::Representation::WitnessMethod) {
auto protocolName = *attrs.conventionWitnessMethodProtocol;
witnessMethodProtocol = new (TC.Context) SimpleIdentTypeRepr(
SourceLoc(), TC.Context.getIdentifier(protocolName));
}
}
// Resolve the function type directly with these attributes.
SILFunctionType::ExtInfo extInfo(rep, attrs.has(TAK_pseudogeneric),
attrs.has(TAK_noescape));
ty = resolveSILFunctionType(fnRepr, options, coroutineKind,
extInfo, calleeConvention,
witnessMethodProtocol);
if (!ty || ty->hasError()) return ty;
} else if (hasFunctionAttr) {
FunctionType::Representation rep = FunctionType::Representation::Swift;
if (attrs.hasConvention()) {
auto parsedRep =
llvm::StringSwitch<Optional<FunctionType::Representation>>
(attrs.getConvention())
.Case("swift", FunctionType::Representation::Swift)
.Case("block", FunctionType::Representation::Block)
.Case("thin", FunctionType::Representation::Thin)
.Case("c", FunctionType::Representation::CFunctionPointer)
.Default(None);
if (!parsedRep) {
TC.diagnose(attrs.getLoc(TAK_convention),
diag::unsupported_convention, attrs.getConvention());
rep = FunctionType::Representation::Swift;
} else {
rep = *parsedRep;
}
}
// @autoclosure is only valid on parameters.
if (!isParam && attrs.has(TAK_autoclosure)) {
TC.diagnose(attrs.getLoc(TAK_autoclosure),
isVariadicFunctionParam
? diag::attr_not_on_variadic_parameters
: diag::attr_only_on_parameters, "@autoclosure");
attrs.clearAttribute(TAK_autoclosure);
}
auto *FuncTyInput = fnRepr->getArgsTypeRepr();
if ((!FuncTyInput || FuncTyInput->getNumElements() != 0)
&& attrs.has(TAK_autoclosure)) {
TC.diagnose(attrs.getLoc(TAK_autoclosure),
diag::autoclosure_function_input_nonunit);
attrs.clearAttribute(TAK_autoclosure);
}
// @noreturn has been replaced with a 'Never' return type.
if (attrs.has(TAK_noreturn)) {
auto loc = attrs.getLoc(TAK_noreturn);
auto attrRange = getTypeAttrRangeWithAt(TC, loc);
auto resultRange = fnRepr->getResultTypeRepr()->getSourceRange();
TC.diagnose(loc, diag::noreturn_not_supported)
.fixItRemove(attrRange)
.fixItReplace(resultRange, "Never");
}
// Resolve the function type directly with these attributes.
FunctionType::ExtInfo extInfo(rep,
attrs.has(TAK_autoclosure),
attrs.has(TAK_noescape),
fnRepr->throws());
ty = resolveASTFunctionType(fnRepr, options, extInfo);
if (!ty || ty->hasError()) return ty;
}
auto instanceOptions = options;
instanceOptions -= TypeResolutionFlags::FunctionInput;
instanceOptions -= TypeResolutionFlags::TypeAliasUnderlyingType;
// If we didn't build the type differently above, we might have
// a typealias pointing at a function type with the @escaping
// attribute. Resolve the type as if it were in non-parameter
// context, and then set isNoEscape if @escaping is not present.
if (!ty) ty = resolveType(repr, instanceOptions);
if (!ty || ty->hasError()) return ty;
// Handle @escaping
if (hasFunctionAttr && ty->is<FunctionType>()) {
if (attrs.has(TAK_escaping)) {
// The attribute is meaningless except on parameter types.
bool isEnum = options.contains(TypeResolutionFlags::EnumCase);
if (isEnum || !isParam) {
auto loc = attrs.getLoc(TAK_escaping);
auto attrRange = getTypeAttrRangeWithAt(TC, loc);
TC.diagnose(loc, diag::escaping_non_function_parameter)
.fixItRemove(attrRange);
// Try to find a helpful note based on how the type is being used
if (options.contains(TypeResolutionFlags::ImmediateOptionalTypeArgument)) {
TC.diagnose(repr->getLoc(), diag::escaping_optional_type_argument);
}
}
attrs.clearAttribute(TAK_escaping);
} else {
// No attribute; set the isNoEscape bit if we're in parameter context.
ty = applyNonEscapingFromContext(DC, ty, options);
}
}
if (hasFunctionAttr && !fnRepr) {
// @autoclosure usually auto-implies @noescape, don't complain about both
// of them.
if (attrs.has(TAK_autoclosure))
attrs.clearAttribute(TAK_noescape);
for (auto i : FunctionAttrs) {
if (!attrs.has(i))
continue;
auto diag = TC.diagnose(attrs.getLoc(i),
diag::attribute_requires_function_type,
TypeAttributes::getAttrName(i));
// If we see @escaping among the attributes on this type, because it isn't
// a function type, we'll remove it.
if (i == TAK_escaping) {
diag.fixItRemove(getTypeAttrRangeWithAt(TC,
attrs.getLoc(TAK_escaping)));
// Specialize the diagnostic for Optionals.
if (ty->getOptionalObjectType()) {
diag.flush();
TC.diagnose(repr->getLoc(), diag::escaping_optional_type_argument);
}
}
attrs.clearAttribute(i);
}
} else if (hasFunctionAttr && fnRepr) {
// Remove the function attributes from the set so that we don't diagnose.
for (auto i : FunctionAttrs)
attrs.clearAttribute(i);
attrs.convention = None;
}
// In SIL, handle @opened (n), which creates an existential archetype.
if (attrs.has(TAK_opened)) {
if (!ty->isExistentialType()) {
TC.diagnose(attrs.getLoc(TAK_opened), diag::opened_non_protocol, ty);
} else {
ty = ArchetypeType::getOpened(ty, attrs.OpenedID);
}
attrs.clearAttribute(TAK_opened);
}
// In SIL files *only*, permit @weak and @unowned to apply directly to types.
if (attrs.hasOwnership()) {
if (auto SF = DC->getParentSourceFile()) {
if (SF->Kind == SourceFileKind::SIL) {
if (((attrs.has(TAK_sil_weak) || attrs.has(TAK_sil_unmanaged)) &&
ty->getOptionalObjectType()) ||
(!attrs.has(TAK_sil_weak) && ty->hasReferenceSemantics())) {
ty = ReferenceStorageType::get(ty, attrs.getOwnership(), Context);
attrs.clearOwnership();
}
}
}
}
// In SIL *only*, allow @block_storage to specify a block storage type.
if ((options & TypeResolutionFlags::SILType) && attrs.has(TAK_block_storage)) {
ty = SILBlockStorageType::get(ty->getCanonicalType());
attrs.clearAttribute(TAK_block_storage);
}
// In SIL *only*, allow @box to specify a box type.
if ((options & TypeResolutionFlags::SILType) && attrs.has(TAK_box)) {
ty = SILBoxType::get(ty->getCanonicalType());
attrs.clearAttribute(TAK_box);
}
// In SIL *only*, allow @dynamic_self to specify a dynamic Self type.
if ((options & TypeResolutionFlags::SILMode) && attrs.has(TAK_dynamic_self)) {
ty = rebuildWithDynamicSelf(TC.Context, ty);
attrs.clearAttribute(TAK_dynamic_self);
}
for (unsigned i = 0; i != TypeAttrKind::TAK_Count; ++i)
if (attrs.has((TypeAttrKind)i))
TC.diagnose(attrs.getLoc((TypeAttrKind)i),
diag::attribute_does_not_apply_to_type);
return ty;
}
bool TypeResolver::resolveASTFunctionTypeParams(
TupleTypeRepr *inputRepr, TypeResolutionOptions options,
bool requiresMappingOut,
SmallVectorImpl<AnyFunctionType::Param> &elements) {
elements.reserve(inputRepr->getNumElements());
const auto elementOptions = withoutContext(options, true)
| TypeResolutionFlags::FunctionInput;
for (unsigned i = 0, end = inputRepr->getNumElements(); i != end; ++i) {
auto *eltTypeRepr = inputRepr->getElementType(i);
// If the element is a variadic parameter, resolve the parameter type as if
// it were in non-parameter position, since we want functions to be
// @escaping in this case.
auto thisElementOptions = elementOptions;
bool variadic = false;
if (inputRepr->hasEllipsis() &&
elements.size() == inputRepr->getEllipsisIndex()) {
thisElementOptions = withoutContext(elementOptions);
thisElementOptions |= TypeResolutionFlags::VariadicFunctionInput;
variadic = true;
}
Type ty = resolveType(eltTypeRepr, thisElementOptions);
if (!ty) return true;
if (ty->hasError()) {
elements.emplace_back(ErrorType::get(Context), Identifier(),
ParameterTypeFlags());
continue;
}
// Parameters of polymorphic functions speak in terms of interface types.
if (requiresMappingOut) {
ty = ty->mapTypeOutOfContext();
}
ValueOwnership ownership;
switch (eltTypeRepr->getKind()) {
case TypeReprKind::Shared:
ownership = ValueOwnership::Shared;
break;
case TypeReprKind::InOut:
ownership = ValueOwnership::InOut;
break;
case TypeReprKind::Owned:
ownership = ValueOwnership::Owned;
break;
default:
ownership = ValueOwnership::Default;
break;
}
ParameterTypeFlags paramFlags =
ParameterTypeFlags::fromParameterType(ty, variadic, ownership);
elements.emplace_back(ty->getInOutObjectType(), Identifier(), paramFlags);
}
return false;
}
Type TypeResolver::resolveASTFunctionType(FunctionTypeRepr *repr,
TypeResolutionOptions options,
FunctionType::ExtInfo extInfo) {
options -= TypeResolutionFlags::FunctionInput;
options -= TypeResolutionFlags::TypeAliasUnderlyingType;
options -= TypeResolutionFlags::AllowIUO;
SmallVector<AnyFunctionType::Param, 8> params;
if (resolveASTFunctionTypeParams(repr->getArgsTypeRepr(), options,
repr->getGenericEnvironment() != nullptr, params)) {
return Type();
}
Type outputTy = resolveType(repr->getResultTypeRepr(), options);
if (!outputTy || outputTy->hasError()) return outputTy;
extInfo = extInfo.withThrows(repr->throws());
// If this is a function type without parens around the parameter list,
// diagnose this and produce a fixit to add them.
if (!repr->isWarnedAbout()) {
// If someone wrote (Void) -> () in Swift 3, they probably meant
// () -> (), but (Void) -> () is (()) -> () so emit a warning
// asking if they meant () -> ().
auto args = repr->getArgsTypeRepr();
if (args->getNumElements() == 1) {
if (const auto Void =
dyn_cast<SimpleIdentTypeRepr>(args->getElementType(0))) {
if (Void->getIdentifier().str() == "Void") {
TC.diagnose(args->getStartLoc(), diag::paren_void_probably_void)
.fixItReplace(args->getSourceRange(), "()");
repr->setWarned();
}
}
}
}
// SIL uses polymorphic function types to resolve overloaded member functions.
if (auto genericEnv = repr->getGenericEnvironment()) {
outputTy = outputTy->mapTypeOutOfContext();
return GenericFunctionType::get(genericEnv->getGenericSignature(),
params, outputTy, extInfo);
}
auto fnTy = FunctionType::get(params, outputTy, extInfo);
// If the type is a block or C function pointer, it must be representable in
// ObjC.
switch (auto rep = extInfo.getRepresentation()) {
case AnyFunctionType::Representation::Block:
case AnyFunctionType::Representation::CFunctionPointer:
if (!fnTy->isRepresentableIn(ForeignLanguage::ObjectiveC, DC)) {
StringRef strName =
rep == AnyFunctionType::Representation::Block ? "block" : "c";
auto extInfo2 =
extInfo.withRepresentation(AnyFunctionType::Representation::Swift);
auto simpleFnTy = FunctionType::get(params, outputTy, extInfo2);
TC.diagnose(repr->getStartLoc(), diag::objc_convention_invalid,
simpleFnTy, strName);
}
break;
case AnyFunctionType::Representation::Thin:
case AnyFunctionType::Representation::Swift:
break;
}
return fnTy;
}
Type TypeResolver::resolveSILBoxType(SILBoxTypeRepr *repr,
TypeResolutionOptions options) {
// Resolve the field types.
SmallVector<SILField, 4> fields;
{
// Resolve field types using the box type's generic environment, if it
// has one. (TODO: Field types should never refer to generic parameters
// outside the box's own environment; we should really validate that...)
Optional<GenericTypeToArchetypeResolver>
resolveSILBoxGenericParams;
Optional<llvm::SaveAndRestore<GenericTypeResolver*>>
useSILBoxGenericEnv;
if (auto env = repr->getGenericEnvironment()) {
resolveSILBoxGenericParams = GenericTypeToArchetypeResolver(env);
useSILBoxGenericEnv.emplace(Resolver, &*resolveSILBoxGenericParams);
}
for (auto &fieldRepr : repr->getFields()) {
auto fieldTy = resolveType(fieldRepr.getFieldType(), options);
fields.push_back({fieldTy->getCanonicalType(), fieldRepr.isMutable()});
}
}
// Substitute out parsed context types into interface types.
CanGenericSignature genericSig;
if (auto *genericEnv = repr->getGenericEnvironment()) {
genericSig = genericEnv->getGenericSignature()->getCanonicalSignature();
for (auto &field : fields) {
auto transTy = field.getLoweredType()->mapTypeOutOfContext();
field = {transTy->getCanonicalType(), field.isMutable()};
}
}
// Resolve the generic arguments.
// Start by building a TypeSubstitutionMap.
SubstitutionMap subMap;
if (genericSig) {
TypeSubstitutionMap genericArgMap;
auto params = genericSig->getGenericParams();
if (repr->getGenericArguments().size()
!= genericSig->getGenericParams().size()) {
TC.diagnose(repr->getLoc(), diag::sil_box_arg_mismatch);
return ErrorType::get(Context);
}
for (unsigned i : indices(params)) {
auto argTy = resolveType(repr->getGenericArguments()[i], options);
genericArgMap.insert({params[i], argTy->getCanonicalType()});
}
bool ok = true;
subMap = SubstitutionMap::get(
genericSig,
QueryTypeSubstitutionMap{genericArgMap},
[&](CanType depTy, Type replacement, ProtocolDecl *proto)
-> ProtocolConformanceRef {
auto result = TC.conformsToProtocol(replacement, proto, DC,
ConformanceCheckOptions());
// TODO: getSubstitutions callback ought to return Optional.
if (!result) {
ok = false;
return ProtocolConformanceRef(proto);
}
return *result;
});
if (!ok)
return ErrorType::get(Context);
}
auto layout = SILLayout::get(Context, genericSig, fields);
return SILBoxType::get(Context, layout, subMap);
}
Type TypeResolver::resolveSILFunctionType(FunctionTypeRepr *repr,
TypeResolutionOptions options,
SILCoroutineKind coroutineKind,
SILFunctionType::ExtInfo extInfo,
ParameterConvention callee,
TypeRepr *witnessMethodProtocol) {
options -= TypeResolutionFlags::FunctionInput;
options -= TypeResolutionFlags::TypeAliasUnderlyingType;
bool hasError = false;
// Resolve parameter and result types using the function's generic
// environment.
SmallVector<SILParameterInfo, 4> params;
SmallVector<SILYieldInfo, 4> yields;
SmallVector<SILResultInfo, 4> results;
Optional<SILResultInfo> errorResult;
{
Optional<GenericTypeToArchetypeResolver>
resolveSILFunctionGenericParams;
Optional<llvm::SaveAndRestore<GenericTypeResolver*>>
useSILFunctionGenericEnv;
// Resolve generic params using the function's generic environment, if it
// has one.
if (auto env = repr->getGenericEnvironment()) {
resolveSILFunctionGenericParams = GenericTypeToArchetypeResolver(env);
useSILFunctionGenericEnv.emplace(Resolver,
&*resolveSILFunctionGenericParams);
}
auto argsTuple = repr->getArgsTypeRepr();
// SIL functions cannot be variadic.
if (argsTuple->hasEllipsis()) {
TC.diagnose(argsTuple->getEllipsisLoc(), diag::sil_function_ellipsis);
}
// SIL functions cannot have parameter names.
for (auto &element : argsTuple->getElements()) {
if (element.UnderscoreLoc.isValid())
TC.diagnose(element.UnderscoreLoc, diag::sil_function_input_label);
}
for (auto elt : argsTuple->getElements()) {
auto param = resolveSILParameter(elt.Type,
options | TypeResolutionFlags::FunctionInput);
params.push_back(param);
if (!param.getType()) return nullptr;
if (param.getType()->hasError())
hasError = true;
}
{
// FIXME: Deal with unsatisfied dependencies.
if (resolveSILResults(repr->getResultTypeRepr(), options, yields,
results, errorResult)) {
hasError = true;
}
// Diagnose non-coroutines that declare yields.
if (coroutineKind == SILCoroutineKind::None && !yields.empty()) {
TC.diagnose(repr->getResultTypeRepr()->getLoc(),
diag::sil_non_coro_yields);
hasError = true;
}
}
} // restore generic type resolver
if (hasError) {
return ErrorType::get(Context);
}
// FIXME: Remap the parsed context types to interface types.
CanGenericSignature genericSig;
SmallVector<SILParameterInfo, 4> interfaceParams;
SmallVector<SILYieldInfo, 4> interfaceYields;
SmallVector<SILResultInfo, 4> interfaceResults;
Optional<SILResultInfo> interfaceErrorResult;
if (auto *genericEnv = repr->getGenericEnvironment()) {
genericSig = genericEnv->getGenericSignature()->getCanonicalSignature();
for (auto &param : params) {
auto transParamType = param.getType()->mapTypeOutOfContext()
->getCanonicalType();
interfaceParams.push_back(param.getWithType(transParamType));
}
for (auto &yield : yields) {
auto transYieldType = yield.getType()->mapTypeOutOfContext()
->getCanonicalType();
interfaceYields.push_back(yield.getWithType(transYieldType));
}
for (auto &result : results) {
auto transResultType = result.getType()->mapTypeOutOfContext()
->getCanonicalType();
interfaceResults.push_back(result.getWithType(transResultType));
}
if (errorResult) {
auto transErrorResultType = errorResult->getType()->mapTypeOutOfContext()
->getCanonicalType();
interfaceErrorResult =
errorResult->getWithType(transErrorResultType);
}
} else {
interfaceParams = params;
interfaceYields = yields;
interfaceResults = results;
interfaceErrorResult = errorResult;
}
Optional<ProtocolConformanceRef> witnessMethodConformance;
if (witnessMethodProtocol) {
auto resolved = resolveType(witnessMethodProtocol, options);
if (resolved->hasError())
return resolved;
auto protocolType = resolved->getAs<ProtocolType>();
if (!protocolType)
return ErrorType::get(Context);
Type selfType = params.back().getType();
// The Self type can be nested in a few layers of metatypes (etc.), e.g. for
// a mutable static variable the materializeForSet currently has its last
// argument as a Self.Type.Type metatype.
while (1) {
auto next = selfType->getRValueInstanceType();
if (next->isEqual(selfType))
break;
selfType = next;
}
witnessMethodConformance = TC.conformsToProtocol(
selfType, protocolType->getDecl(), DC, ConformanceCheckOptions());
assert(witnessMethodConformance &&
"found witness_method without matching conformance");
}
return SILFunctionType::get(genericSig, extInfo, coroutineKind,
callee,
interfaceParams, interfaceYields,
interfaceResults, interfaceErrorResult,
Context, witnessMethodConformance);
}
SILYieldInfo TypeResolver::resolveSILYield(TypeAttributes &attrs,
TypeRepr *repr,
TypeResolutionOptions options) {
AttributedTypeRepr attrRepr(attrs, repr);
SILParameterInfo paramInfo =
resolveSILParameter(&attrRepr,
options | TypeResolutionFlags::FunctionInput);
return SILYieldInfo(paramInfo.getType(), paramInfo.getConvention());
}
SILParameterInfo TypeResolver::resolveSILParameter(
TypeRepr *repr,
TypeResolutionOptions options) {
assert(options.contains(TypeResolutionFlags::FunctionInput)
&& "Parameters should be marked as inputs");
auto convention = DefaultParameterConvention;
Type type;
bool hadError = false;
if (auto attrRepr = dyn_cast<AttributedTypeRepr>(repr)) {
auto attrs = attrRepr->getAttrs();
auto checkFor = [&](TypeAttrKind tak, ParameterConvention attrConv) {
if (!attrs.has(tak)) return;
if (convention != DefaultParameterConvention) {
TC.diagnose(attrs.getLoc(tak), diag::sil_function_repeat_convention,
/*input*/ 0);
hadError = true;
}
attrs.clearAttribute(tak);
convention = attrConv;
};
checkFor(TypeAttrKind::TAK_in_guaranteed,
ParameterConvention::Indirect_In_Guaranteed);
checkFor(TypeAttrKind::TAK_in, ParameterConvention::Indirect_In);
checkFor(TypeAttrKind::TAK_in_constant,
ParameterConvention::Indirect_In_Constant);
checkFor(TypeAttrKind::TAK_inout, ParameterConvention::Indirect_Inout);
checkFor(TypeAttrKind::TAK_inout_aliasable,
ParameterConvention::Indirect_InoutAliasable);
checkFor(TypeAttrKind::TAK_owned, ParameterConvention::Direct_Owned);
checkFor(TypeAttrKind::TAK_guaranteed,
ParameterConvention::Direct_Guaranteed);
type = resolveAttributedType(attrs, attrRepr->getTypeRepr(), options);
} else {
type = resolveType(repr, options);
}
if (!type || type->hasError()) {
hadError = true;
// Diagnose types that are illegal in SIL.
} else if (!type->isLegalSILType()) {
TC.diagnose(repr->getLoc(), diag::illegal_sil_type, type);
hadError = true;
}
if (hadError) type = ErrorType::get(Context);
return SILParameterInfo(type->getCanonicalType(), convention);
}
bool TypeResolver::resolveSingleSILResult(TypeRepr *repr,
TypeResolutionOptions options,
SmallVectorImpl<SILYieldInfo> &yields,
SmallVectorImpl<SILResultInfo> &ordinaryResults,
Optional<SILResultInfo> &errorResult) {
Type type;
auto convention = DefaultResultConvention;
bool isErrorResult = false;
if (auto attrRepr = dyn_cast<AttributedTypeRepr>(repr)) {
// Copy the attributes out; we're going to destructively modify them.
auto attrs = attrRepr->getAttrs();
// Recognize @yields.
if (attrs.has(TypeAttrKind::TAK_yields)) {
attrs.clearAttribute(TypeAttrKind::TAK_yields);
// The treatment from this point on is basically completely different.
auto yield = resolveSILYield(attrs, attrRepr->getTypeRepr(), options);
if (yield.getType()->hasError())
return true;
yields.push_back(yield);
return false;
}
// Recognize @error.
if (attrs.has(TypeAttrKind::TAK_error)) {
attrs.clearAttribute(TypeAttrKind::TAK_error);
isErrorResult = true;
// Error results are always implicitly @owned.
convention = ResultConvention::Owned;
}
// Recognize result conventions.
bool hadError = false;
auto checkFor = [&](TypeAttrKind tak, ResultConvention attrConv) {
if (!attrs.has(tak)) return;
if (convention != DefaultResultConvention) {
TC.diagnose(attrs.getLoc(tak), diag::sil_function_repeat_convention,
/*result*/ 1);
hadError = true;
}
attrs.clearAttribute(tak);
convention = attrConv;
};
checkFor(TypeAttrKind::TAK_out, ResultConvention::Indirect);
checkFor(TypeAttrKind::TAK_owned, ResultConvention::Owned);
checkFor(TypeAttrKind::TAK_unowned_inner_pointer,
ResultConvention::UnownedInnerPointer);
checkFor(TypeAttrKind::TAK_autoreleased, ResultConvention::Autoreleased);
if (hadError) return true;
type = resolveAttributedType(attrs, attrRepr->getTypeRepr(), options);
} else {
type = resolveType(repr, options);
}
// Propagate type-resolution errors out.
if (!type || type->hasError()) return true;
// Diagnose types that are illegal in SIL.
if (!type->isLegalSILType()) {
TC.diagnose(repr->getStartLoc(), diag::illegal_sil_type, type);
return false;
}
assert(!isErrorResult || convention == ResultConvention::Owned);
SILResultInfo resolvedResult(type->getCanonicalType(), convention);
if (!isErrorResult) {
ordinaryResults.push_back(resolvedResult);
return false;
}
// Error result types must have pointer-like representation.
// FIXME: check that here?
// We don't expect to have a reason to support multiple independent
// error results. (Would this be disjunctive or conjunctive?)
if (errorResult.hasValue()) {
TC.diagnose(repr->getStartLoc(),
diag::sil_function_multiple_error_results);
return true;
}
errorResult = resolvedResult;
return false;
}
bool TypeResolver::resolveSILResults(TypeRepr *repr,
TypeResolutionOptions options,
SmallVectorImpl<SILYieldInfo> &yields,
SmallVectorImpl<SILResultInfo> &ordinaryResults,
Optional<SILResultInfo> &errorResult) {
if (auto tuple = dyn_cast<TupleTypeRepr>(repr)) {
bool hadError = false;
for (auto &element : tuple->getElements()) {
if (element.UnderscoreLoc.isValid())
TC.diagnose(element.UnderscoreLoc, diag::sil_function_output_label);
}
for (auto elt : tuple->getElements()) {
if (resolveSingleSILResult(elt.Type, options,
yields, ordinaryResults, errorResult))
hadError = true;
}
return hadError;
}
return resolveSingleSILResult(repr, options,
yields, ordinaryResults, errorResult);
}
Type TypeResolver::resolveSpecifierTypeRepr(SpecifierTypeRepr *repr,
TypeResolutionOptions options) {
// inout is only valid for (non-Subscript and non-EnumCaseDecl)
// function parameters.
if ((options & TypeResolutionFlags::SubscriptParameters) ||
(options & TypeResolutionFlags::EnumCase) ||
(!(options & TypeResolutionFlags::FunctionInput))) {
decltype(diag::attr_only_on_parameters) diagID;
if (options & TypeResolutionFlags::SubscriptParameters) {
diagID = diag::attr_not_on_subscript_parameters;
} else if (options & TypeResolutionFlags::VariadicFunctionInput) {
diagID = diag::attr_not_on_variadic_parameters;
} else {
diagID = diag::attr_only_on_parameters;
}
StringRef name;
switch (repr->getKind()) {
case TypeReprKind::InOut:
name = "inout";
break;
case TypeReprKind::Shared:
name = "__shared";
break;
case TypeReprKind::Owned:
name = "__owned";
break;
default:
llvm_unreachable("unknown SpecifierTypeRepr kind");
}
TC.diagnose(repr->getSpecifierLoc(), diagID, name);
repr->setInvalid();
return ErrorType::get(Context);
}
// Anything within the inout isn't a parameter anymore.
options -= TypeResolutionFlags::FunctionInput;
options -= TypeResolutionFlags::TypeAliasUnderlyingType;
Type ty = resolveType(repr->getBase(), options);
if (!ty || ty->hasError()) return ty;
if (repr->getKind() == TypeReprKind::InOut) return InOutType::get(ty);
return ty;
}
Type TypeResolver::resolveArrayType(ArrayTypeRepr *repr,
TypeResolutionOptions options) {
// FIXME: diagnose non-materializability of element type!
Type baseTy = resolveType(repr->getBase(), withoutContext(options));
if (!baseTy || baseTy->hasError()) return baseTy;
auto sliceTy = TC.getArraySliceType(repr->getBrackets().Start, baseTy);
if (!sliceTy)
return ErrorType::get(Context);
if (!options.contains(TypeResolutionFlags::ResolveStructure)) {
// Check for _ObjectiveCBridgeable conformances in the element type.
TC.useObjectiveCBridgeableConformances(DC, baseTy);
}
return sliceTy;
}
Type TypeResolver::resolveDictionaryType(DictionaryTypeRepr *repr,
TypeResolutionOptions options) {
options = adjustOptionsForGenericArgs(options);
// FIXME: diagnose non-materializability of key/value type?
Type keyTy = resolveType(repr->getKey(), withoutContext(options));
if (!keyTy || keyTy->hasError()) return keyTy;
Type valueTy = resolveType(repr->getValue(), withoutContext(options));
if (!valueTy || valueTy->hasError()) return valueTy;
auto dictDecl = TC.Context.getDictionaryDecl();
if (auto dictTy = TC.getDictionaryType(repr->getBrackets().Start, keyTy,
valueTy)) {
// Check the requirements on the generic arguments.
auto unboundTy = dictDecl->getDeclaredType()->castTo<UnboundGenericType>();
if (!options.contains(TypeResolutionFlags::ResolveStructure)) {
Type args[] = {keyTy, valueTy};
if (!TC.applyUnboundGenericArguments(
unboundTy, dictDecl, repr->getStartLoc(), DC, args,
Resolver)) {
return nullptr;
}
// Check for _ObjectiveCBridgeable conformances in the key and value
// types.
TC.useObjectiveCBridgeableConformances(DC, keyTy);
TC.useObjectiveCBridgeableConformances(DC, valueTy);
}
return dictTy;
}
return ErrorType::get(Context);
}
Type TypeResolver::resolveOptionalType(OptionalTypeRepr *repr,
TypeResolutionOptions options) {
auto elementOptions = withoutContext(options, true);
elementOptions |= TypeResolutionFlags::ImmediateOptionalTypeArgument;
// The T in T? is a generic type argument and therefore always an AST type.
// FIXME: diagnose non-materializability of element type!
Type baseTy = resolveType(repr->getBase(), elementOptions);
if (!baseTy || baseTy->hasError()) return baseTy;
auto optionalTy = TC.getOptionalType(repr->getQuestionLoc(), baseTy);
if (!optionalTy) return ErrorType::get(Context);
return optionalTy;
}
Type TypeResolver::resolveImplicitlyUnwrappedOptionalType(
ImplicitlyUnwrappedOptionalTypeRepr *repr,
TypeResolutionOptions options) {
if (!options.contains(TypeResolutionFlags::AllowIUO)) {
if (options.contains(TypeResolutionFlags::AllowIUODeprecated)) {
TC.diagnose(
repr->getStartLoc(),
diag::implicitly_unwrapped_optional_deprecated_in_this_position);
} else if (!TC.Context.isSwiftVersionAtLeast(5)) {
TC.diagnose(
repr->getStartLoc(),
diag::
implicitly_unwrapped_optional_in_illegal_position_interpreted_as_optional)
.fixItReplace(repr->getExclamationLoc(), "?");
} else {
TC.diagnose(repr->getStartLoc(),
diag::implicitly_unwrapped_optional_in_illegal_position)
.fixItReplace(repr->getExclamationLoc(), "?");
}
}
auto elementOptions = withoutContext(options, true);
elementOptions |= TypeResolutionFlags::ImmediateOptionalTypeArgument;
// The T in T! is a generic type argument and therefore always an AST type.
// FIXME: diagnose non-materializability of element type!
Type baseTy = resolveType(repr->getBase(), elementOptions);
if (!baseTy || baseTy->hasError()) return baseTy;
Type uncheckedOptionalTy;
uncheckedOptionalTy = TC.getOptionalType(repr->getExclamationLoc(), baseTy);
if (!uncheckedOptionalTy)
return ErrorType::get(Context);
return uncheckedOptionalTy;
}
Type TypeResolver::resolveTupleType(TupleTypeRepr *repr,
TypeResolutionOptions options) {
SmallVector<TupleTypeElt, 8> elements;
elements.reserve(repr->getNumElements());
auto elementOptions = options;
if (repr->isParenType()) {
// We also want to disallow IUO within even a paren.
elementOptions -= TypeResolutionFlags::AllowIUO;
} else {
elementOptions = withoutContext(elementOptions, true);
}
// Variadic tuples are not permitted.
bool complained = false;
if (repr->hasEllipsis()) {
TC.diagnose(repr->getEllipsisLoc(), diag::tuple_ellipsis);
repr->removeEllipsis();
complained = true;
}
for (unsigned i = 0, end = repr->getNumElements(); i != end; ++i) {
auto *tyR = repr->getElementType(i);
Type ty = resolveType(tyR, elementOptions);
if (!ty || ty->hasError()) return ty;
elements.emplace_back(ty->getInOutObjectType(),
repr->getElementName(i), ParameterTypeFlags());
}
// Single-element labeled tuples are not permitted outside of declarations
// or SIL, either.
if (elements.size() == 1 && elements[0].hasName()
&& !(options & TypeResolutionFlags::SILType)) {
if (!complained) {
TC.diagnose(repr->getElementNameLoc(0),
diag::tuple_single_element)
.fixItRemoveChars(repr->getElementNameLoc(0),
repr->getElementType(0)->getStartLoc());
}
elements[0] = TupleTypeElt(elements[0].getType());
}
return TupleType::get(elements, Context);
}
Type TypeResolver::resolveCompositionType(CompositionTypeRepr *repr,
TypeResolutionOptions options) {
// Note that the superclass type will appear as part of one of the
// types in 'Members', so it's not used when constructing the
// fully-realized type below -- but we just record it to make sure
// there is only one superclass.
Type SuperclassType;
SmallVector<Type, 4> Members;
// Whether we saw at least one protocol. A protocol composition
// must either be empty (in which case it is Any or AnyObject),
// or if it has a superclass constraint, have at least one protocol.
bool HasProtocol = false;
auto checkSuperclass = [&](SourceLoc loc, Type t) -> bool {
if (SuperclassType && !SuperclassType->isEqual(t)) {
TC.diagnose(loc, diag::protocol_composition_one_class, t,
SuperclassType);
return true;
}
SuperclassType = t;
return false;
};
for (auto tyR : repr->getTypes()) {
Type ty = resolveType(tyR, withoutContext(options));
if (!ty || ty->hasError()) return ty;
auto nominalDecl = ty->getAnyNominal();
if (nominalDecl && isa<ClassDecl>(nominalDecl)) {
if (checkSuperclass(tyR->getStartLoc(), ty))
continue;
Members.push_back(ty);
continue;
}
if (ty->isExistentialType()) {
auto layout = ty->getExistentialLayout();
if (auto superclass = layout.explicitSuperclass)
if (checkSuperclass(tyR->getStartLoc(), superclass))
continue;
if (!layout.getProtocols().empty())
HasProtocol = true;
Members.push_back(ty);
continue;
}
TC.diagnose(tyR->getStartLoc(),
diag::invalid_protocol_composition_member,
ty);
}
// Avoid confusing diagnostics ('MyClass' not convertible to 'MyClass',
// etc) by collapsing a composition consisting of a single class down
// to the class itself.
if (SuperclassType && !HasProtocol)
return SuperclassType;
// In user-written types, AnyObject constraints always refer to the
// AnyObject type in the standard library.
return ProtocolCompositionType::get(Context, Members,
/*HasExplicitAnyObject=*/false);
}
Type TypeResolver::resolveMetatypeType(MetatypeTypeRepr *repr,
TypeResolutionOptions options) {
// The instance type of a metatype is always abstract, not SIL-lowered.
Type ty = resolveType(repr->getBase(), withoutContext(options));
if (!ty || ty->hasError()) return ty;
Optional<MetatypeRepresentation> storedRepr;
// In SIL mode, a metatype must have a @thin, @thick, or
// @objc_metatype attribute, so metatypes should have been lowered
// in resolveAttributedType.
if (options & TypeResolutionFlags::SILType) {
TC.diagnose(repr->getStartLoc(), diag::sil_metatype_without_repr);
storedRepr = MetatypeRepresentation::Thick;
}
return buildMetatypeType(repr, ty, storedRepr);
}
Type TypeResolver::buildMetatypeType(
MetatypeTypeRepr *repr,
Type instanceType,
Optional<MetatypeRepresentation> storedRepr) {
if (instanceType->isAnyExistentialType()) {
// TODO: diagnose invalid representations?
return ExistentialMetatypeType::get(instanceType, storedRepr);
} else {
return MetatypeType::get(instanceType, storedRepr);
}
}
Type TypeResolver::resolveProtocolType(ProtocolTypeRepr *repr,
TypeResolutionOptions options) {
// The instance type of a metatype is always abstract, not SIL-lowered.
Type ty = resolveType(repr->getBase(), withoutContext(options));
if (!ty || ty->hasError()) return ty;
Optional<MetatypeRepresentation> storedRepr;
// In SIL mode, a metatype must have a @thin, @thick, or
// @objc_metatype attribute, so metatypes should have been lowered
// in resolveAttributedType.
if (options & TypeResolutionFlags::SILType) {
TC.diagnose(repr->getStartLoc(), diag::sil_metatype_without_repr);
storedRepr = MetatypeRepresentation::Thick;
}
return buildProtocolType(repr, ty, storedRepr);
}
Type TypeResolver::buildProtocolType(
ProtocolTypeRepr *repr,
Type instanceType,
Optional<MetatypeRepresentation> storedRepr) {
if (!instanceType->isAnyExistentialType()) {
TC.diagnose(repr->getProtocolLoc(), diag::dot_protocol_on_non_existential,
instanceType);
return ErrorType::get(TC.Context);
}
return MetatypeType::get(instanceType, storedRepr);
}
Type TypeChecker::substMemberTypeWithBase(ModuleDecl *module,
TypeDecl *member,
Type baseTy,
bool useArchetypes) {
Type sugaredBaseTy = baseTy;
// For type members of a base class, make sure we use the right
// derived class as the parent type.
if (auto *ownerClass = member->getDeclContext()
->getAsClassOrClassExtensionContext()) {
baseTy = baseTy->getSuperclassForDecl(ownerClass, useArchetypes);
}
if (baseTy->is<ModuleType>()) {
baseTy = Type();
sugaredBaseTy = Type();
}
// The declared interface type for a generic type will have the type
// arguments; strip them off.
if (auto *nominalDecl = dyn_cast<NominalTypeDecl>(member)) {
// If the base type is not a nominal type, we might be looking up a
// nominal member of a generic parameter. This is not supported right
// now, but at least don't crash.
if (member->getDeclContext()->getAsProtocolOrProtocolExtensionContext())
return nominalDecl->getDeclaredType();
if (!isa<ProtocolDecl>(nominalDecl) &&
nominalDecl->getGenericParams()) {
return UnboundGenericType::get(
nominalDecl, baseTy,
nominalDecl->getASTContext());
}
return NominalType::get(
nominalDecl, baseTy,
nominalDecl->getASTContext());
}
auto *aliasDecl = dyn_cast<TypeAliasDecl>(member);
if (aliasDecl) {
// FIXME: If this is a protocol typealias and we haven't built the
// protocol's generic environment yet, do so now, to ensure the
// typealias's underlying type has fully resolved dependent
// member types.
if (auto *protoDecl = dyn_cast<ProtocolDecl>(aliasDecl->getDeclContext()))
if (protoDecl->getGenericEnvironment() == nullptr)
validateDecl(protoDecl);
if (aliasDecl->getGenericParams()) {
return UnboundGenericType::get(
aliasDecl, baseTy,
aliasDecl->getASTContext());
}
}
Type resultType;
auto memberType = aliasDecl ? aliasDecl->getUnderlyingTypeLoc().getType()
: member->getDeclaredInterfaceType();
SubstitutionMap subs;
if (baseTy) {
// Cope with the presence of unbound generic types, which are ill-formed
// at this point but break the invariants of getContextSubstitutionMap().
if (baseTy->hasUnboundGenericType()) {
if (memberType->hasTypeParameter())
return ErrorType::get(memberType);
return memberType;
}
subs = baseTy->getContextSubstitutionMap(module, member->getDeclContext());
resultType = memberType.subst(subs, SubstFlags::UseErrorType);
} else {
resultType = memberType;
}
// If we're referring to a typealias within a generic context, build
// a sugared alias type.
if (aliasDecl && (!sugaredBaseTy || !sugaredBaseTy->isAnyExistentialType())) {
resultType = NameAliasType::get(aliasDecl, sugaredBaseTy, subs,
resultType);
}
return resultType;
}
Type TypeChecker::getSuperClassOf(Type type) {
if (auto *parenTy = dyn_cast<ParenType>(type.getPointer())) {
auto superclassTy = getSuperClassOf(parenTy->getUnderlyingType());
if (!superclassTy)
return Type();
return ParenType::get(Context, superclassTy);
}
return type->getSuperclass();
}
namespace {
class UnsupportedProtocolVisitor
: public TypeReprVisitor<UnsupportedProtocolVisitor>, public ASTWalker
{
TypeChecker &TC;
bool checkStatements;
bool hitTopStmt;
public:
UnsupportedProtocolVisitor(TypeChecker &tc, bool checkStatements)
: TC(tc), checkStatements(checkStatements), hitTopStmt(false) { }
bool walkToTypeReprPre(TypeRepr *T) override {
if (T->isInvalid())
return false;
if (auto compound = dyn_cast<CompoundIdentTypeRepr>(T)) {
// Only visit the last component to check, because nested typealiases in
// existentials are okay.
visit(compound->getComponentRange().back());
return false;
}
visit(T);
return true;
}
std::pair<bool, Stmt*> walkToStmtPre(Stmt *S) override {
if (checkStatements && !hitTopStmt) {
hitTopStmt = true;
return { true, S };
}
return { false, S };
}
bool walkToDeclPre(Decl *D) override {
return !checkStatements;
}
void visitIdentTypeRepr(IdentTypeRepr *T) {
if (T->isInvalid())
return;
auto comp = T->getComponentRange().back();
if (auto *proto = dyn_cast_or_null<ProtocolDecl>(comp->getBoundDecl())) {
if (!proto->existentialTypeSupported(&TC)) {
TC.diagnose(comp->getIdLoc(), diag::unsupported_existential_type,
proto->getName());
T->setInvalid();
}
} else if (auto *alias = dyn_cast_or_null<TypeAliasDecl>(comp->getBoundDecl())) {
if (!alias->hasInterfaceType())
return;
auto type = Type(alias->getDeclaredInterfaceType()->getDesugaredType());
type.findIf([&](Type type) -> bool {
if (T->isInvalid())
return false;
if (type->isExistentialType()) {
auto layout = type->getExistentialLayout();
for (auto *proto : layout.getProtocols()) {
auto *protoDecl = proto->getDecl();
if (protoDecl->existentialTypeSupported(&TC))
continue;
TC.diagnose(comp->getIdLoc(), diag::unsupported_existential_type,
protoDecl->getName());
T->setInvalid();
}
}
return false;
});
}
}
};
} // end anonymous namespace
void TypeChecker::checkUnsupportedProtocolType(Decl *decl) {
if (!decl || decl->isInvalid())
return;
// Type declarations are okay.
if (isa<TypeDecl>(decl))
return;
// Extensions are okay.
if (isa<ExtensionDecl>(decl))
return;
UnsupportedProtocolVisitor visitor(*this, /*checkStatements=*/false);
decl->walk(visitor);
}
void TypeChecker::checkUnsupportedProtocolType(Stmt *stmt) {
if (!stmt)
return;
UnsupportedProtocolVisitor visitor(*this, /*checkStatements=*/true);
stmt->walk(visitor);
}