A type variable that represents a key path literal cannot be bound
directly to `AnyKeyPath` or `PartialKeyPath`, such types could only
be used for conversions.
It used to be the task of the binding inference to infer `AnyKeyPath`
and `PartiaKeyPath` as a `KeyPath` using previously generated type
variables for a root and value associated with key path literal
(previously stored in the locator).
Recently we switched over to storing key path information in the
constraint system and introduced `resolveKeyPath` method to gain
more control over how key path type variable gets assigned.
Getting information from the constraint system creates a problem
for the inference because "undo" for some bindings would be run
after solver scope has been erased, so instead of modifying bindings
in `inferFromRelational`, let's do that in `resolveKeyPath` right
before the key path type variable gets bound which seems to be a
better place for that logic anyway.
Resolves: rdar://113760727
llvm::SmallSetVector changed semantics
(https://reviews.llvm.org/D152497) resulting in build failures in Swift.
The old semantics allowed usage of types that did not have an
`operator==` because `SmallDenseSet` uses `DenseSetInfo<T>::isEqual` to
determine equality. The new implementation switched to using
`std::find`, which internally uses `operator==`. This type is used
pretty frequently with `swift::Type`, which intentionally deletes
`operator==` as it is not the canonical type and therefore cannot be
compared in normal circumstances.
This patch adds a new type-alias to the Swift namespace that provides
the old semantic behavior for `SmallSetVector`. I've also gone through
and replaced usages of `llvm::SmallSetVector` with the
`Swift::SmallSetVector` in places where we're storing a type that
doesn't implement or explicitly deletes `operator==`. The changes to
`llvm::SmallSetVector` should improve compile-time performance, so I
left the `llvm::SmallSetVector` where possible.
If a closure doesn't have a contextual type inferred yet it should
be delayed in favor of already resolved closure conjunction because
"resolving" such a closure early could miss result builder attribute
attached to a parameter the closure is passed to.
Partially resolves https://github.com/apple/swift/issues/67363
Ignore conversion score increases during code completion to make sure we don't filter solutions that might start receiving the best score based on a choice of the code completion token.
Reformatting everything now that we have `llvm` namespaces. I've
separated this from the main commit to help manage merge-conflicts and
for making it a bit easier to read the mega-patch.
This is phase-1 of switching from llvm::Optional to std::optional in the
next rebranch. llvm::Optional was removed from upstream LLVM, so we need
to migrate off rather soon. On Darwin, std::optional, and llvm::Optional
have the same layout, so we don't need to be as concerned about ABI
beyond the name mangling. `llvm::Optional` is only returned from one
function in
```
getStandardTypeSubst(StringRef TypeName,
bool allowConcurrencyManglings);
```
It's the return value, so it should not impact the mangling of the
function, and the layout is the same as `std::optional`, so it should be
mostly okay. This function doesn't appear to have users, and the ABI was
already broken 2 years ago for concurrency and no one seemed to notice
so this should be "okay".
I'm doing the migration incrementally so that folks working on main can
cherry-pick back to the release/5.9 branch. Once 5.9 is done and locked
away, then we can go through and finish the replacement. Since `None`
and `Optional` show up in contexts where they are not `llvm::None` and
`llvm::Optional`, I'm preparing the work now by going through and
removing the namespace unwrapping and making the `llvm` namespace
explicit. This should make it fairly mechanical to go through and
replace llvm::Optional with std::optional, and llvm::None with
std::nullopt. It's also a change that can be brought onto the
release/5.9 with minimal impact. This should be an NFC change.
Rather than eagerly binding them to holes if the
sequence element type ends up being Any, let's
record the CollectionElementContextualMismatch fix,
and then if the patterns end up becoming holes,
skip penalizing them if we know the fix was
recorded. This avoids prematurely turning type
variables for ExprPatterns into holes, which
should be able to get better bindings from the
expression provided. Also this means we'll apply
the logic to non-Any sequence types, which
previously we would give a confusing diagnostic
to.
The constraint takes two pack types and makes sure that their
reduced shapes are equal. This helps with diagnostics because
constraint has access to the original pack expansion pattern
types.
It's only safe to infer element type from `PackElementOf` constraint
when pattern type is fully resolved (because it can have pack element
archetypes which should be mapped out of context), the same applies
to the pattern type inference as well. Since constraints are re-activated
every time a referenced type variable is bound, simplication logic
can act as inference source by decaying into `Equal` constraints
where pattern/element type are resolved via surrounding information
first.
Diagnose base inference failure only if base gets inferred to be
a placeholder, any transitive placeholder inference points to the
problem being elsewhere.
Print bound type variables as `$T<Num> as <Type> @ <locator>` and
unbound ones as `$T<Num> [allows bindings to: ...] [attributes: ...] ... @ <locator>`
This simplifies the representation and allows clients to handle fewer
cases. It also removes an ambiguity in the representation which could
lead us to have two canonical types for the same type.
This is definitely not working yet, but I'm not making progress on
it quickly enough to unblock what we need to unblock; it'll have to
be fixed in parallel.
The _Copyable constraint was implemented as a marker protocol.
That protocol is part of the KnownProtocol's in the compiler.
When `ASTContext::getProtocol(KnownProtocolKind kind)` tries
to find the ProtocolDecl for Copyable, it will look in the
stdlib module (i.e., Swift module), which is where I initially
planned to put it.
That created problems initially when some regression tests
use `-parse-stdlib` failed to do that protocol lookup, which is
essential for adding the constraint (given the current implementation).
That led to believe we need to pull Copyable out of the stdlib, but that's
wrong. In fact, when building the Swift module itself, we do `-parse-stdlib`
but we also include `-module-name Swift`. This causes the _Copyable protocol
defined in the Stdlib to be correctly discovered while building the stdlib
itself (see the test case in this commit). So, the only downside of
having the Copyable protocol in the Stdlib is that `-parse-stdlib` tests
in the compiler can't use move-only types correctly, as they'll be
allowed in generic contexts. No real program would build like this.
Until I have time to do a further refactoring, this is an acceptable trade-off.
fixes rdar://104898230
If a result builder transformed closure doesn't rely on any external
type information it could be solved right after it's resolved. We
determine that based on three criteria:
- Builder type doesn't have any unresolved generic parameters;
- Closure doesn't have any parameters;
- The contextual result type is either concrete or opaque type.
constraints, vend potential bindings through PotentialBindings::infer.
This allows for bidirectional binding inference from the pack type to the
element type and vice versa.
Enable type checking support for explicitly specifying generic arguments to
a macro, e.g., `#stringify<Double>(1 + 2)`. To do so, introduce a new
kind of constraint that performs explicit argument matching against the
generic parameters of a macro only after the overload is chosen.
`getValue` -> `value`
`getValueOr` -> `value_or`
`hasValue` -> `has_value`
`map` -> `transform`
The old API will be deprecated in the rebranch.
To avoid merge conflicts, use the new API already in the main branch.
rdar://102362022