This will be used to provide a safe overload of `std::vector::erase` in Swift.
`std::vector::erase` is not currently imported into Swift because it returns a C++ iterator.
rdar://113704853
This fixes a compiler error when building SwiftCompilerSources in hosttools mode with a recent Xcode.
```
<unknown>:0: error: calling a private constructor of class 'clang::StmtIterator'
swift/llvm-project/clang/include/clang/AST/StmtIterator.h:137:3: note: declared private here
StmtIterator(const StmtIteratorBase &RHS)
^
```
rdar://113514872
I discovered this when experimenting with `std::map::iterator`, which has a const overload of `operator*` that returns a non-const reference, and does not have a const overload of `operator*`.
rdar://112471779
This is an inheritor of the existing `UnsafeCxxInputIterator` protocol, with the only difference being the ability to mutate `var pointee` via a non-const `operator*()`.
This is needed to support mutable subscripts for `std::map` via `CxxDictionary`.
rdar://105399019
C++ `T& operator*()` is mapped to a Swift computed property `var pointee: T`.
Previously `var pointee` only had a getter, after this change it will also have a setter if the C++ type declares an overload of `operator*` that returns a mutable reference.
rdar://112471779
This fixes the automatic `std::unordered_map` conformance to CxxDictionary on Linux. Previously `std::unordered_map::const_iterator` was not auto-conformed to UnsafeCxxInputIterator because its `operator==` is defined on a templated base class of `const_iterator`.
rdar://105220600
This adds a new Swift overload for `append` that takes another `std::string` as a parameter.
The original C++ overload for `append` is not exposed into Swift because it returns a mutable reference `string&`.
rdar://107018724
The compiler might optimize away the first copy, so just make sure that no copies are happening during the actual initialization of Array.
rdar://110422053
Currently without an initializer for the unsafe char pointer type swiftc
hits an assert around not being able to handle conversions of unsafe
pointers with Any type. This patch adds the ability to convert to a
std::string.
This is to address issue https://github.com/apple/swift/issues/61218
This disables TBD validation when C++ interop is enabled, unless an explicit `-validate-tbd-against-ir=` flag was passed.
rdar://83405989 / https://github.com/apple/swift/issues/56458
The original C++ operators are not currently imported into Swift because they are defined as a non-member templated functions.
This change adds the operators as Swift extension functions. This also adds an `Equatable` conformance for `std::string`.
rdar://107017882
This makes sure that Swift is only auto-conforming C++ container types to `CxxSequence`/`CxxConvertibleToCollection` if they expose non-mutating `begin()` and `end()` methods.
We might want to make `begin()` and `end()` non-mutating in the near future to enable performance optimizations. This change makes sure that client code relying on the automatic conformances doesn't suddenly stop compiling if/when the mutability requirement on the protocol function changes.
`Swift.String` can be initialized from any other type with an unlabeled initializer, which is either going to use the `CustomStringConvertible` conformance, or reflection. We would like clients to use the most suitable initializer, which is the one that takes `std.string` as a parameter. For instance, that allows us to attach a doc comment to the initializer.
This change makes the initializer unlabeled to make sure it is chosed by overload resolution when a client invokes `String(myCxxString)`.
C++ iterator types are often templated, and sometimes declare `operator==` as a non-member templated function. In libc++, an example of this is `__wrap_iter` which is used as an iterator type for `std::vector` and `std::string`.
We don't currently import templated non-member operators into Swift, however, we still want to support common C++ iterator patterns.
This change adds logic to instantiate templated non-member `operator==` for types that define `iterator_category` and are therefore likely to be valid iterator types.
rdar://97915515
If an operator is declared as a method of a templated class, we were failing to look it up during auto-conformance to `UnsafeCxxInputIterator`.
This fixes `Interop/Cxx/stdlib/use-std-map.swift` on Ubuntu.
rdar://102420290
This extends the existing auto-conformance mechanism to synthesize the conformances to `CxxConvertibleToCollection` protocol for C++ sequence types.
This means that the developer can now call `Array(myCxxSequence)` or `Set(myCxxSequence)` without adding any extensions manually.
Since we don't automatically conform C++ non-random-access collections to `Swift.Sequence` anymore for performance reasons, we need an alternative way to access the elements of a C++ sequence from Swift.
This allows explicitly converting a C++ sequence to a Swift Array/Set.
This became an issue in rebranch: multiple interop tests started failing (e.g. `Interop/Cxx/foreign-reference/pod.swift`).
The problem is not specific to rebranch though.
rdar://102151836
Iterating over a `CxxSequence` that is not a `CxxRandomAccessCollection` triggers a copy of the C++ collection. Let's disable the automatic conformances until we find a more efficient solution.
This means that for now developers won't be able to iterate over a `std::set` or `std::list` with a Swift for-in loop. I will submit a separate patch with an alternative solution for such types.
C++ random access collections, such as `std::vector` or `std::string`, are not affected.
This makes ClangImporter automatically conform C++ collection types to `Cxx.CxxRandomAccessCollection` protocol.
We consider a C++ sequence type to be a random access collection type its iterator conforms to `UnsafeCxxRandomAccessIterator`.
This fixes a couple cases of cases where a malformed C++ iterator type would trigger an assertion in ClangImporter: `Assertion failed: (Val && "isa<> used on a null pointer")`.
This makes ClangImporter automatically conform C++ sequence types to `Cxx.UnsafeCxxInputIterator` protocol.
We consider a C++ type to be a random access iterator type if conforms to `UnsafeCxxInputIterator`, and additionally defines `operator-` and `operator+=`.
This lifts the requirement for the user to explicitly add `import Cxx` in Swift code that relies on protocols from the `Cxx` module, such as `CxxSequence`.
This helps to bridge C++ random access collections, such as `std::vector` and `std::string`, to Swift by conforming them to `Swift.RandomAccessCollection`
To determine whether to conform a C++ type to `CxxSequence` protocol automatically, ClangImporter checks if the corresponding iterator type conforms to `UnsafeCxxInputIterator`.
This logic had false-positives, e.g. `Optional<OpaquePointer>` was treated as if it conforms to `UnsafeCxxInputIterator` while it actually doesn't. This happened because `lookupConformance` returned a conformance with a conditional requirement (`Wrapped : UnsafeCxxInputIterator`) that is not satisfied for `OpaquePointer`.
rdar://100265664
Previously the conversion mechanism called `std::string::c_str` and passed it to `String(cString:)` which accepts a null-terminated string. If the string contains a `\0` character, this failed to initialize the entire string properly.