averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-14 20:36:38 +01:00
Code Issues Packages Projects Releases Wiki Activity

[SE-0413] Adopt typed throws in withoutActuallyEscaping(_:do:)

Browse Source 
There is a small bug fix here in the identification of the catch node,
where the leading `{` of a closure was considered to be "inside" the
closure for code like

    { ... }()

causing us to assume that the call to the closure would catch the error
within the closure.

Other than that, introduce the thrown error type into the type checker's
modeling of `withoutActuallyEscaping(_:do:)`, and mirror that in the
library declaration.
This commit is contained in:
Doug Gregor
2024-01-13 21:57:24 -08:00
parent 0b2cc84dbf
commit 8912d4aa71
7 changed files with 92 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
lib/AST/ASTScopeLookup.cpp
View File

@@ -704,6 +704,21 @@ getCatchNode(const ASTScopeImpl *scope) {
return { CatchNode(), nullptr };
}
/// Check whether the given location precedes the start of the catch location
/// despite being technically within the catch node's source range.
static bool locationIsPriorToStartOfCatchScope(SourceLoc loc, CatchNode node) {
auto closure = node.dyn_cast<ClosureExpr *>();
if (!closure)
return false;
SourceManager &sourceMgr = closure->getASTContext().SourceMgr;
SourceLoc inLoc = closure->getInLoc();
if (inLoc.isValid())
return sourceMgr.isBefore(loc, inLoc);
return sourceMgr.isAtOrBefore(loc, closure->getStartLoc());
}
CatchNode ASTScopeImpl::lookupCatchNode(ModuleDecl *module, SourceLoc loc) {
auto sourceFile = module->getSourceFileContainingLocation(loc);
if (!sourceFile)
@@ -721,7 +736,8 @@ CatchNode ASTScopeImpl::lookupCatchNode(ModuleDecl *module, SourceLoc loc) {
// If we are at a catch node and in the body of the region from which that
// node catches thrown errors, we have our result.
auto caught = getCatchNode(scope);
if (caught.first && caught.second == innerBodyScope) {
if (caught.first && caught.second == innerBodyScope &&
!locationIsPriorToStartOfCatchScope(loc, caught.first)) {
return caught.first;
}

7
lib/Sema/ConstraintSystem.cpp
View File

@@ -3108,12 +3108,15 @@ static DeclReferenceType getTypeOfReferenceWithSpecialTypeCheckingSemantics(
auto result = CS.createTypeVariable(
CS.getConstraintLocator(locator, ConstraintLocator::FunctionResult),
TVO_CanBindToNoEscape);
auto thrownError = CS.createTypeVariable(
CS.getConstraintLocator(locator, ConstraintLocator::ThrownErrorType),
0);
FunctionType::Param arg(escapeClosure);
auto bodyClosure = FunctionType::get(arg, result,
FunctionType::ExtInfoBuilder()
.withNoEscape(true)
.withAsync(true)
.withThrows(true, /*FIXME:*/Type())
.withThrows(true, thrownError)
.build());
FunctionType::Param args[] = {
FunctionType::Param(noescapeClosure),
@@ -3124,7 +3127,7 @@ static DeclReferenceType getTypeOfReferenceWithSpecialTypeCheckingSemantics(
FunctionType::ExtInfoBuilder()
.withNoEscape(false)
.withAsync(true)
.withThrows(true, /*FIXME:*/Type())
.withThrows(true, thrownError)
.build());
return {refType, refType, refType, refType, Type()};
}

20
stdlib/public/core/Builtin.swift
View File

@@ -1022,12 +1022,28 @@ public func type<T, Metatype>(of value: T) -> Metatype {
/// - body: A closure that is executed immediately with an escapable copy of
/// `closure` as its argument.
/// - Returns: The return value, if any, of the `body` closure.
@_alwaysEmitIntoClient
@_transparent
@_semantics("typechecker.withoutActuallyEscaping(_:do:)")
public func withoutActuallyEscaping<ClosureType, ResultType>(
public func withoutActuallyEscaping<ClosureType, ResultType, Failure>(
_ closure: ClosureType,
do body: (_ escapingClosure: ClosureType) throws(Failure) -> ResultType
) throws(Failure) -> ResultType {
// This implementation is never used, since calls to
// `Swift.withoutActuallyEscaping(_:do:)` are resolved as a special case by
// the type checker.
Builtin.staticReport(_trueAfterDiagnostics(), true._value,
("internal consistency error: 'withoutActuallyEscaping(_:do:)' operation failed to resolve"
as StaticString).utf8Start._rawValue)
Builtin.unreachable()
}
@_silgen_name("$ss23withoutActuallyEscaping_2doq_x_q_xKXEtKr0_lF")
@usableFromInline
func __abi_withoutActuallyEscaping<ClosureType, ResultType>(
_ closure: ClosureType,
do body: (_ escapingClosure: ClosureType) throws -> ResultType
) rethrows -> ResultType {
) throws -> ResultType {
// This implementation is never used, since calls to
// `Swift.withoutActuallyEscaping(_:do:)` are resolved as a special case by
// the type checker.

25
test/Constraints/without_actually_escaping.swift
View File

@@ -60,10 +60,8 @@ func rethrowThroughWAE(_ zz: (Int, Int, Int) throws -> Int, _ value: Int) throws
}
}
// There should be two errors - here one for async -> sync, and another throws -> non-throws
let _: ((Int) -> Int, (@escaping (Int) -> Int) -> ()) -> () = withoutActuallyEscaping(_:do:)
// expected-error@-1 {{invalid conversion from throwing function of type '((Int) -> Int, (@escaping (Int) -> Int) async throws -> ()) async throws -> ()' to non-throwing function type '((Int) -> Int, (@escaping (Int) -> Int) -> ()) -> ()'}}
// expected-error@-2 {{invalid conversion from 'async' function of type '((Int) -> Int, (@escaping (Int) -> Int) async throws -> ()) async throws -> ()' to synchronous function type '((Int) -> Int, (@escaping (Int) -> Int) -> ()) -> ()'}}
// expected-error@-1 {{invalid conversion from 'async' function of type '((Int) -> Int, (@escaping (Int) -> Int) async -> ()) async -> ()' to synchronous function type '((Int) -> Int, (@escaping (Int) -> Int) -> ()) -> ()'}}
// Failing to propagate @noescape into non-single-expression
@@ -91,3 +89,24 @@ class Box<T> {
}
}
}
enum HomeworkError: Error {
case forgot
case dogAteIt
}
enum MyError: Error {
case fail
}
func letEscapeThrowTyped(f: () throws(HomeworkError) -> () -> ()) throws(HomeworkError) -> () -> () {
// Note: thrown error type inference for closures will fix this error below.
return try withoutActuallyEscaping(f) { return try $0() }
// expected-error@-1{{thrown expression type 'any Error' cannot be converted to error type 'HomeworkError'}}
}
func letEscapeThrowTypedBad(f: () throws(HomeworkError) -> () -> ()) throws(MyError) -> () -> () {
// Note: thrown error type inference for closures will change this error below.
return try withoutActuallyEscaping(f) { return try $0() }
// expected-error@-1{{thrown expression type 'any Error' cannot be converted to error type 'MyError'}}
}

26
test/SILGen/without_actually_escaping.swift
View File

@@ -51,9 +51,31 @@ func letEscapeThrow(f: () throws -> () -> ()) throws -> () -> () {
return try withoutActuallyEscaping(f) { return try $0() }
}
// thunk for @callee_guaranteed () -> (@owned @escaping @callee_guaranteed () -> (), @error @owned Error)
enum HomeworkError: Error {
case forgot
case dogAteIt
}
// CHECK-LABEL: sil hidden [ossa] @$s25without_actually_escaping19letEscapeThrowTyped1fyycyycyAA13HomeworkErrorOYKXE_tKF : $@convention(thin) (@guaranteed @noescape @callee_guaranteed () -> (@owned @callee_guaranteed () -> (), @error HomeworkError)) -> (@owned @callee_guaranteed () -> (), @error any Error)
// CHECK: bb0([[ARG:%.*]] : @guaranteed $@noescape @callee_guaranteed () -> (@owned @callee_guaranteed () -> (), @error HomeworkError)):
// CHECK: function_ref @$sIeg_25without_actually_escaping13HomeworkErrorOIgozo_Ieg_ACIegozo_TR : $@convention(thin) (@guaranteed @noescape @callee_guaranteed () -> (@owned @callee_guaranteed () -> (), @error HomeworkError)) -> (@owned @callee_guaranteed () -> (), @error HomeworkError)
// CHECK: bb2([[ERR:%.*]] : @owned $any Error):
// CHECK: end_borrow [[BORROW]]
// CHECK: destroy_value [[MD]]
// CHECK: throw [[ERR]] : $any Error
// CHECK: }
func letEscapeThrowTyped(f: () throws(HomeworkError) -> () -> ()) throws -> () -> () {
return try withoutActuallyEscaping(f) { return try $0() }
}
// The thunk must be [without_actually_escaping].
// CHECK-LABEL: sil shared [transparent] [serialized] [reabstraction_thunk] [without_actually_escaping] [ossa] @$sIeg_s5Error_pIgozo_Ieg_sAA_pIegozo_TR : $@convention(thin) (@guaranteed @noescape @callee_guaranteed () -> (@owned @callee_guaranteed () -> (), @error any Error)) -> (@owned @callee_guaranteed () -> (), @error any Error) {
// CHECK-LABEL: sil shared [transparent] [serialized] [reabstraction_thunk] [without_actually_escaping] [ossa] @$sIeg_25without_actually_escaping13HomeworkErrorOIgozo_Ieg_ACIegozo_TR : $@convention(thin) (@guaranteed @noescape @callee_guaranteed () -> (@owned @callee_guaranteed () -> (), @error HomeworkError)) -> (@owned @callee_guaranteed () -> (), @error HomeworkError)
func letEscapeThrowTyped2(f: () throws(HomeworkError) -> () -> ()) throws(HomeworkError) -> () -> () {
return try withoutActuallyEscaping(f) { (g) throws(HomeworkError) in return try g() }
}
// We used to crash on this example because we would use the wrong substitution
// map.

2
test/api-digester/Outputs/stability-stdlib-source-x86_64.swift.expected
View File

@@ -41,5 +41,7 @@ Func Collection.map(_:) is now without @rethrows
Func Sequence.map(_:) has generic signature change from <Self, T where Self : Swift.Sequence> to <Self, T, E where Self : Swift.Sequence, E : Swift.Error>
Func Sequence.map(_:) is now without @rethrows
Constructor Result.init(catching:) has generic signature change from <Success, Failure where Failure == any Swift.Error> to <Success, Failure where Failure : Swift.Error>
Func withoutActuallyEscaping(_:do:) has generic signature change from <ClosureType, ResultType> to <ClosureType, ResultType, Failure where Failure : Swift.Error>
Func withoutActuallyEscaping(_:do:) is now without @rethrows
Protocol SIMDScalar has generic signature change from <Self == Self.SIMD16Storage.Scalar, Self.SIMD16Storage : Swift.SIMDStorage, Self.SIMD2Storage : Swift.SIMDStorage, Self.SIMD32Storage : Swift.SIMDStorage, Self.SIMD4Storage : Swift.SIMDStorage, Self.SIMD64Storage : Swift.SIMDStorage, Self.SIMD8Storage : Swift.SIMDStorage, Self.SIMDMaskScalar : Swift.FixedWidthInteger, Self.SIMDMaskScalar : Swift.SIMDScalar, Self.SIMDMaskScalar : Swift.SignedInteger, Self.SIMD16Storage.Scalar == Self.SIMD2Storage.Scalar, Self.SIMD2Storage.Scalar == Self.SIMD32Storage.Scalar, Self.SIMD32Storage.Scalar == Self.SIMD4Storage.Scalar, Self.SIMD4Storage.Scalar == Self.SIMD64Storage.Scalar, Self.SIMD64Storage.Scalar == Self.SIMD8Storage.Scalar> to <Self == Self.SIMD16Storage.Scalar, Self.SIMD16Storage : Swift.SIMDStorage, Self.SIMD2Storage : Swift.SIMDStorage, Self.SIMD32Storage : Swift.SIMDStorage, Self.SIMD4Storage : Swift.SIMDStorage, Self.SIMD64Storage : Swift.SIMDStorage, Self.SIMD8Storage : Swift.SIMDStorage, Self.SIMDMaskScalar : Swift.FixedWidthInteger, Self.SIMDMaskScalar : Swift.SIMDScalar, Self.SIMDMaskScalar : Swift.SignedInteger, Self.SIMDMaskScalar == Self.SIMDMaskScalar.SIMDMaskScalar, Self.SIMD16Storage.Scalar == Self.SIMD2Storage.Scalar, Self.SIMD2Storage.Scalar == Self.SIMD32Storage.Scalar, Self.SIMD32Storage.Scalar == Self.SIMD4Storage.Scalar, Self.SIMD4Storage.Scalar == Self.SIMD64Storage.Scalar, Self.SIMD64Storage.Scalar == Self.SIMD8Storage.Scalar>

4
test/api-digester/stability-stdlib-abi-without-asserts.test
View File

@@ -99,6 +99,10 @@ Constructor Result.init(__abi_catching:) is a new API without @available attribu
Constructor Result.init(catching:) has been removed
Func Result.get() has been renamed to Func __abi_get()
Func Result.get() has mangled name changing from 'Swift.Result.get() throws -> A' to 'Swift.Result.__abi_get() throws -> A'
Func withoutActuallyEscaping(_:do:) has been renamed to Func __abi_withoutActuallyEscaping(_:do:)
Func withoutActuallyEscaping(_:do:) has mangled name changing from 'Swift.withoutActuallyEscaping<A, B>(_: A, do: (A) throws -> B) throws -> B' to 'Swift.__abi_withoutActuallyEscaping<A, B>(_: A, do: (A) throws -> B) throws -> B'
Func withoutActuallyEscaping(_:do:) is now without @rethrows
// These haven't actually been removed; they are simply marked unavailable.
// This seems to be a false positive in the ABI checker. This is not an ABI