Files
swift-mirror/lib/Sema/DerivedConformanceRawRepresentable.cpp
Doug Gregor 41ae48b22e Start parsing 'throws' on initializers.
Introduce basic validation for throwing @objc initializers, e.g., a
failable @objc initializer cannot also be throwing. However,
Objective-C selector computation is broken.

Swift SVN r27292
2015-04-14 22:52:29 +00:00

545 lines
21 KiB
C++

//===--- DerivedConformanceRawRepresentable.cpp - Derived RawRepresentable ===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file implements implicit derivation of the RawRepresentable protocol
// for an enum.
//
//===----------------------------------------------------------------------===//
#include "TypeChecker.h"
#include "llvm/Support/raw_ostream.h"
#include "swift/AST/ArchetypeBuilder.h"
#include "swift/AST/Decl.h"
#include "swift/AST/Stmt.h"
#include "swift/AST/Expr.h"
#include "swift/AST/Pattern.h"
#include "swift/AST/Types.h"
#include "DerivedConformances.h"
using namespace swift;
using namespace DerivedConformance;
void DerivedConformance::_insertOperatorDecl(NominalTypeDecl *scope,
Decl *member) {
// Find the module.
auto &C = scope->getASTContext();
auto mod = scope->getModuleContext();
// Add it to the module in a DerivedFileUnit.
mod->getDerivedFileUnit().addDerivedDecl(cast<FuncDecl>(member));
// Add it as a derived global decl to the nominal type.
auto oldDerived = scope->getDerivedGlobalDecls();
auto oldSize = std::distance(oldDerived.begin(), oldDerived.end());
auto newDerived = C.Allocate<Decl*>(oldSize + 1);
std::move(oldDerived.begin(), oldDerived.end(), newDerived.begin());
newDerived[oldSize] = member;
scope->setDerivedGlobalDecls(newDerived);
}
static LiteralExpr *cloneRawLiteralExpr(ASTContext &C, LiteralExpr *expr) {
LiteralExpr *clone;
if (auto intLit = dyn_cast<IntegerLiteralExpr>(expr)) {
clone = new (C) IntegerLiteralExpr(intLit->getDigitsText(), SourceLoc(),
/*implicit*/ true);
if (intLit->isNegative())
cast<IntegerLiteralExpr>(clone)->setNegative(SourceLoc());
} else if (isa<NilLiteralExpr>(expr)) {
clone = new (C) NilLiteralExpr(SourceLoc());
} else if (auto charLit = dyn_cast<CharacterLiteralExpr>(expr)) {
clone = new (C) CharacterLiteralExpr(charLit->getValue(), SourceLoc());
} else if (auto stringLit = dyn_cast<StringLiteralExpr>(expr)) {
clone = new (C) StringLiteralExpr(stringLit->getValue(), SourceLoc());
} else if (auto floatLit = dyn_cast<FloatLiteralExpr>(expr)) {
clone = new (C) FloatLiteralExpr(floatLit->getDigitsText(), SourceLoc(),
/*implicit*/ true);
if (floatLit->isNegative())
cast<FloatLiteralExpr>(clone)->setNegative(SourceLoc());
} else {
llvm_unreachable("invalid raw literal expr");
}
clone->setImplicit();
return clone;
}
static TypeDecl *deriveRawRepresentable_Raw(TypeChecker &tc,
EnumDecl *enumDecl) {
// enum SomeEnum : SomeType {
// @derived
// typealias Raw = SomeType
// }
ASTContext &C = tc.Context;
auto rawInterfaceType = enumDecl->getRawType();
auto rawType = ArchetypeBuilder::mapTypeIntoContext(enumDecl,
rawInterfaceType);
auto rawTypeDecl = new (C) TypeAliasDecl(SourceLoc(),
C.Id_RawValue,
SourceLoc(),
TypeLoc::withoutLoc(rawType),
enumDecl);
rawTypeDecl->setImplicit();
rawTypeDecl->setType(rawType);
rawTypeDecl->setInterfaceType(rawInterfaceType);
rawTypeDecl->setAccessibility(enumDecl->getFormalAccess());
enumDecl->addMember(rawTypeDecl);
return rawTypeDecl;
}
DeclRefExpr *
DerivedConformance::createSelfDeclRef(AbstractFunctionDecl *fn) {
ASTContext &C = fn->getASTContext();
Pattern *curriedArgs = fn->getBodyParamPatterns().front();
auto selfPattern =
cast<NamedPattern>(curriedArgs->getSemanticsProvidingPattern());
auto selfDecl = selfPattern->getDecl();
return new (C) DeclRefExpr(selfDecl, SourceLoc(), /*implicit*/true);
}
static void deriveBodyRawRepresentable_raw(AbstractFunctionDecl *toRawDecl) {
// enum SomeEnum : SomeType {
// case A = 111, B = 222
// @derived
// var raw: SomeType {
// switch self {
// case A:
// return 111
// case B:
// return 222
// }
// }
// }
auto enumDecl = cast<EnumDecl>(toRawDecl->getDeclContext());
Type rawTy = enumDecl->getRawType();
assert(rawTy);
for (auto elt : enumDecl->getAllElements()) {
if (!elt->getTypeCheckedRawValueExpr() ||
!elt->getTypeCheckedRawValueExpr()->getType()->isEqual(rawTy)) {
return;
}
}
ASTContext &C = enumDecl->getASTContext();
Type enumType = enumDecl->getDeclaredTypeInContext();
SmallVector<CaseStmt*, 4> cases;
for (auto elt : enumDecl->getAllElements()) {
auto pat = new (C) EnumElementPattern(TypeLoc::withoutLoc(enumType),
SourceLoc(), SourceLoc(),
Identifier(), elt, nullptr);
pat->setImplicit();
auto labelItem =
CaseLabelItem(/*IsDefault=*/false, pat, SourceLoc(), nullptr);
auto returnExpr = cloneRawLiteralExpr(C, elt->getRawValueExpr());
auto returnStmt = new (C) ReturnStmt(SourceLoc(), returnExpr);
auto body = BraceStmt::create(C, SourceLoc(),
ASTNode(returnStmt), SourceLoc());
cases.push_back(CaseStmt::create(C, SourceLoc(), labelItem,
/*HasBoundDecls=*/false, SourceLoc(),
body));
}
auto selfRef = createSelfDeclRef(toRawDecl);
auto switchStmt = SwitchStmt::create(LabeledStmtInfo(), SourceLoc(), selfRef,
SourceLoc(), cases, SourceLoc(), C);
auto body = BraceStmt::create(C, SourceLoc(),
ASTNode(switchStmt),
SourceLoc());
toRawDecl->setBody(body);
}
FuncDecl *DerivedConformance::declareDerivedPropertyGetter(TypeChecker &tc,
NominalTypeDecl *typeDecl,
Type contextType,
Type propertyInterfaceType,
Type propertyContextType) {
auto &C = tc.Context;
VarDecl *selfDecl = new (C) ParamDecl(/*IsLet*/true,
SourceLoc(),
Identifier(),
SourceLoc(),
C.Id_self,
contextType,
typeDecl);
selfDecl->setImplicit();
Pattern *selfParam = new (C) NamedPattern(selfDecl, /*implicit*/ true);
selfParam->setType(contextType);
selfParam = new (C) TypedPattern(selfParam,
TypeLoc::withoutLoc(contextType));
selfParam->setType(contextType);
Pattern *methodParam = TuplePattern::create(C, SourceLoc(),{},SourceLoc());
methodParam->setType(TupleType::getEmpty(C));
Pattern *params[] = {selfParam, methodParam};
FuncDecl *getterDecl =
FuncDecl::create(C, SourceLoc(), StaticSpellingKind::None, SourceLoc(),
DeclName(), SourceLoc(), SourceLoc(), nullptr, Type(),
params, TypeLoc::withoutLoc(propertyContextType),
typeDecl);
getterDecl->setImplicit();
// Compute the type of the getter.
GenericParamList *genericParams = nullptr;
Type type = FunctionType::get(TupleType::getEmpty(C),
propertyContextType);
Type selfType = getterDecl->computeSelfType(&genericParams);
if (genericParams)
type = PolymorphicFunctionType::get(selfType, type, genericParams);
else
type = FunctionType::get(selfType, type);
getterDecl->setType(type);
getterDecl->setBodyResultType(propertyContextType);
// Compute the interface type of the getter.
Type interfaceType = FunctionType::get(TupleType::getEmpty(C),
propertyInterfaceType);
Type selfInterfaceType = getterDecl->computeInterfaceSelfType(false);
if (auto sig = typeDecl->getGenericSignatureOfContext())
interfaceType = GenericFunctionType::get(sig, selfInterfaceType,
interfaceType,
FunctionType::ExtInfo());
else
interfaceType = type;
getterDecl->setInterfaceType(interfaceType);
getterDecl->setAccessibility(typeDecl->getFormalAccess());
if (typeDecl->hasClangNode())
tc.implicitlyDefinedFunctions.push_back(getterDecl);
return getterDecl;
}
std::pair<VarDecl *, PatternBindingDecl *>
DerivedConformance::declareDerivedReadOnlyProperty(TypeChecker &tc,
NominalTypeDecl *typeDecl,
Identifier name,
Type propertyInterfaceType,
Type propertyContextType,
FuncDecl *getterDecl) {
auto &C = tc.Context;
VarDecl *propDecl = new (C) VarDecl(/*static*/ false,
/*let*/ false,
SourceLoc(), name,
propertyContextType,
typeDecl);
propDecl->setImplicit();
propDecl->makeComputed(SourceLoc(), getterDecl, nullptr, nullptr,
SourceLoc());
propDecl->setAccessibility(typeDecl->getFormalAccess());
propDecl->setInterfaceType(propertyInterfaceType);
Pattern *propPat = new (C) NamedPattern(propDecl, /*implicit*/ true);
propPat->setType(propertyContextType);
propPat = new (C) TypedPattern(propPat,
TypeLoc::withoutLoc(propertyContextType),
/*implicit*/ true);
auto pbDecl = PatternBindingDecl::create(C, SourceLoc(),
StaticSpellingKind::None,
SourceLoc(), propPat, nullptr,
typeDecl);
pbDecl->setImplicit();
return {propDecl, pbDecl};
}
static VarDecl *deriveRawRepresentable_raw(TypeChecker &tc,
EnumDecl *enumDecl) {
ASTContext &C = tc.Context;
auto rawInterfaceType = enumDecl->getRawType();
auto rawType = ArchetypeBuilder::mapTypeIntoContext(enumDecl,
rawInterfaceType);
Type enumType = enumDecl->getDeclaredTypeInContext();
// Define the getter.
auto getterDecl = declareDerivedPropertyGetter(tc, enumDecl, enumType,
rawInterfaceType,
rawType);
getterDecl->setBodySynthesizer(&deriveBodyRawRepresentable_raw);
// Define the property.
VarDecl *propDecl;
PatternBindingDecl *pbDecl;
std::tie(propDecl, pbDecl)
= declareDerivedReadOnlyProperty(tc, enumDecl, C.Id_rawValue,
rawType, rawInterfaceType,
getterDecl);
enumDecl->addMember(getterDecl);
enumDecl->addMember(propDecl);
enumDecl->addMember(pbDecl);
return propDecl;
}
static void
deriveBodyRawRepresentable_init(AbstractFunctionDecl *initDecl) {
// enum SomeEnum : SomeType {
// case A = 111, B = 222
// @derived
// init?(rawValue: SomeType) {
// switch rawValue {
// case 111:
// self = .A
// case 222:
// self = .B
// default:
// return nil
// }
// }
// }
auto enumDecl = cast<EnumDecl>(initDecl->getDeclContext());
Type rawTy = enumDecl->getRawType();
assert(rawTy);
rawTy = ArchetypeBuilder::mapTypeIntoContext(initDecl, rawTy);
for (auto elt : enumDecl->getAllElements()) {
if (!elt->getTypeCheckedRawValueExpr() ||
!elt->getTypeCheckedRawValueExpr()->getType()->isEqual(rawTy)) {
return;
}
}
ASTContext &C = enumDecl->getASTContext();
Type enumType = enumDecl->getDeclaredTypeInContext();
auto selfDecl = cast<ConstructorDecl>(initDecl)->getImplicitSelfDecl();
SmallVector<CaseStmt*, 4> cases;
for (auto elt : enumDecl->getAllElements()) {
auto litExpr = cloneRawLiteralExpr(C, elt->getRawValueExpr());
auto litPat = new (C) ExprPattern(litExpr, /*isResolved*/ true,
nullptr, nullptr);
litPat->setImplicit();
auto labelItem =
CaseLabelItem(/*IsDefault=*/false, litPat, SourceLoc(), nullptr);
auto eltRef = new (C) DeclRefExpr(elt, SourceLoc(), /*implicit*/true);
auto metaTyRef = TypeExpr::createImplicit(enumType, C);
auto valueExpr = new (C) DotSyntaxCallExpr(eltRef, SourceLoc(), metaTyRef);
auto selfRef = new (C) DeclRefExpr(selfDecl, SourceLoc(), /*implicit*/true,
AccessSemantics::DirectToStorage);
auto assignment = new (C) AssignExpr(selfRef, SourceLoc(), valueExpr,
/*implicit*/ true);
auto body = BraceStmt::create(C, SourceLoc(),
ASTNode(assignment), SourceLoc());
cases.push_back(CaseStmt::create(C, SourceLoc(), labelItem,
/*HasBoundDecls=*/false, SourceLoc(),
body));
}
auto anyPat = new (C) AnyPattern(SourceLoc());
anyPat->setImplicit();
auto dfltLabelItem =
CaseLabelItem(/*IsDefault=*/true, anyPat, SourceLoc(), nullptr);
auto dfltReturnStmt = new (C) FailStmt(SourceLoc(), SourceLoc());
auto dfltBody = BraceStmt::create(C, SourceLoc(),
ASTNode(dfltReturnStmt), SourceLoc());
cases.push_back(CaseStmt::create(C, SourceLoc(), dfltLabelItem,
/*HasBoundDecls=*/false, SourceLoc(),
dfltBody));
Pattern *args = initDecl->getBodyParamPatterns().back();
auto rawArgPattern = cast<NamedPattern>(args->getSemanticsProvidingPattern());
auto rawDecl = rawArgPattern->getDecl();
auto rawRef = new (C) DeclRefExpr(rawDecl, SourceLoc(), /*implicit*/true);
auto switchStmt = SwitchStmt::create(LabeledStmtInfo(), SourceLoc(), rawRef,
SourceLoc(), cases, SourceLoc(), C);
auto body = BraceStmt::create(C, SourceLoc(),
ASTNode(switchStmt),
SourceLoc());
initDecl->setBody(body);
}
static ConstructorDecl *deriveRawRepresentable_init(TypeChecker &tc,
EnumDecl *enumDecl) {
ASTContext &C = tc.Context;
auto rawInterfaceType = enumDecl->getRawType();
auto rawType = ArchetypeBuilder::mapTypeIntoContext(enumDecl,
rawInterfaceType);
// Make sure that the raw type is Equatable. We need it to ensure that we have
// a suitable ~= for the switch.
auto equatableProto = tc.getProtocol(enumDecl->getLoc(),
KnownProtocolKind::Equatable);
if (!equatableProto)
return nullptr;
if (!tc.conformsToProtocol(rawType, equatableProto, enumDecl,
/*inExpression=*/false)) {
SourceLoc loc = enumDecl->getInherited()[0].getSourceRange().Start;
tc.diagnose(loc, diag::enum_raw_type_not_equatable, rawType);
return nullptr;
}
Type enumType = enumDecl->getDeclaredTypeInContext();
VarDecl *selfDecl = new (C) ParamDecl(/*IsLet*/false,
SourceLoc(),
Identifier(),
SourceLoc(),
C.Id_self,
enumType,
enumDecl);
selfDecl->setImplicit();
Pattern *selfParam = new (C) NamedPattern(selfDecl, /*implicit*/ true);
selfParam->setType(enumType);
selfParam = new (C) TypedPattern(selfParam,
TypeLoc::withoutLoc(enumType));
selfParam->setType(enumType);
selfParam->setImplicit();
VarDecl *rawDecl = new (C) ParamDecl(/*IsVal*/true,
SourceLoc(),
C.Id_rawValue,
SourceLoc(),
C.Id_rawValue,
rawType,
enumDecl);
rawDecl->setImplicit();
Pattern *rawParam = new (C) NamedPattern(rawDecl, /*implicit*/ true);
rawParam->setType(rawType);
rawParam = new (C) TypedPattern(rawParam, TypeLoc::withoutLoc(rawType));
rawParam->setType(rawType);
rawParam->setImplicit();
rawParam = new (C) ParenPattern(SourceLoc(), rawParam, SourceLoc());
rawParam->setType(rawType);
rawParam->setImplicit();
auto retTy = OptionalType::get(enumType);
DeclName name(C, C.Id_init, { C.Id_rawValue });
auto initDecl = new (C) ConstructorDecl(name, SourceLoc(),
/*failability*/ OTK_Optional,
SourceLoc(),
selfParam,
rawParam,
nullptr,
SourceLoc(),
enumDecl);
initDecl->setImplicit();
initDecl->setBodySynthesizer(&deriveBodyRawRepresentable_init);
// Compute the type of the initializer.
GenericParamList *genericParams = nullptr;
TupleTypeElt element(rawType, C.Id_rawValue);
auto argType = TupleType::get(element, C);
TupleTypeElt interfaceElement(rawInterfaceType, C.Id_rawValue);
auto interfaceArgType = TupleType::get(interfaceElement, C);
Type type = FunctionType::get(argType, retTy);
Type selfType = initDecl->computeSelfType(&genericParams);
Type selfMetatype = MetatypeType::get(selfType->getInOutObjectType());
Type allocType;
Type initType;
if (genericParams) {
allocType = PolymorphicFunctionType::get(selfMetatype, type, genericParams);
initType = PolymorphicFunctionType::get(selfType, type, genericParams);
} else {
allocType = FunctionType::get(selfMetatype, type);
initType = FunctionType::get(selfType, type);
}
initDecl->setType(allocType);
initDecl->setInitializerType(initType);
// Compute the interface type of the initializer.
Type retInterfaceType
= OptionalType::get(enumDecl->getDeclaredInterfaceType());
Type interfaceType = FunctionType::get(interfaceArgType, retInterfaceType);
Type selfInterfaceType = initDecl->computeInterfaceSelfType(/*init*/ false);
Type selfInitializerInterfaceType
= initDecl->computeInterfaceSelfType(/*init*/ true);
Type allocIfaceType;
Type initIfaceType;
if (auto sig = enumDecl->getGenericSignatureOfContext()) {
allocIfaceType = GenericFunctionType::get(sig, selfInterfaceType,
interfaceType,
FunctionType::ExtInfo());
initIfaceType = GenericFunctionType::get(sig, selfInitializerInterfaceType,
interfaceType,
FunctionType::ExtInfo());
} else {
allocIfaceType = allocType;
initIfaceType = initType;
}
initDecl->setInterfaceType(allocIfaceType);
initDecl->setInitializerInterfaceType(initIfaceType);
initDecl->setAccessibility(enumDecl->getFormalAccess());
if (enumDecl->hasClangNode())
tc.implicitlyDefinedFunctions.push_back(initDecl);
enumDecl->addMember(initDecl);
return initDecl;
}
ValueDecl *DerivedConformance::deriveRawRepresentable(TypeChecker &tc,
NominalTypeDecl *type,
ValueDecl *requirement) {
// Check preconditions. These should already have been diagnosed by
// type-checking but we may still get here after recovery.
// The type must be an enum.
auto enumDecl = dyn_cast<EnumDecl>(type);
if (!enumDecl)
return nullptr;
// It must have a valid raw type.
if (!enumDecl->hasRawType())
return nullptr;
if (!enumDecl->getInherited().empty() &&
enumDecl->getInherited().front().isError())
return nullptr;
// There must be enum elements.
if (enumDecl->getAllElements().empty())
return nullptr;
for (auto elt : enumDecl->getAllElements())
tc.validateDecl(elt);
if (requirement->getName() == tc.Context.Id_rawValue)
return deriveRawRepresentable_raw(tc, enumDecl);
if (requirement->getName() == tc.Context.Id_init)
return deriveRawRepresentable_init(tc, enumDecl);
if (requirement->getName() == tc.Context.Id_RawValue)
return deriveRawRepresentable_Raw(tc, enumDecl);
tc.diagnose(requirement->getLoc(),
diag::broken_raw_representable_requirement);
return nullptr;
}