Augment the TypeVarRefCollector such that it
picks up any type variables present in the result
type for a closure DeclContext when visiting a
ReturnStmt. This ensures we correctly handle
if/switch expressions that contain `return`
statements.
rdar://114402042
Move the contextual type locator onto
ContextualTypeInfo, and consolidate the separate
fields in SyntacticElementTarget into storing a
ContextualTypeInfo. This then lets us plumb down
the locator for the branch contextual type of an
if/switch expression from the initial constraint
generation, rather than introducing it later. This
should be NFC.
by creating a BoundGenericType for the keypath expr
with the keypath base and replacing the value with
the value typeVar that will be resolved when the value
typeVar is directly bound.
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.
Generate a conjunction for each tap expression body as soon as it
gets a contextual type instead of separate post-factum type-checking
via `typeCheckTapBody`.
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.
Only properties that are listed in 'initializes' and 'accesses'
attributes could be referenced within init accessor. Detect any
and all invalid member references in the solver.
This source location will be used to determine whether to add a name lookup
option to exclude macro expansions when the name lookup request is constructed.
Currently, the source location argument is unused.
Previously we would wait until CSApply, which
would trigger their type-checking in
`coercePatternToType`. This caused a number of
bugs, and hampered solver-based completion, which
does not run CSApply. Instead, form a conjunction
of all the ExprPatterns present, which preserves
some of the previous isolation behavior (though
does not provide complete isolation).
We can then modify `coercePatternToType` to accept
a closure, which allows the solver to take over
rewriting the ExprPatterns it has already solved.
This then sets the stage for the complete removal
of `coercePatternToType`, and doing all pattern
type-checking in the solver.
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.
If there are explicit generic arguments that fully resolves the
pack expansion, let's bind opened pack expansion to its contextual
type early (while resolving pack expansion variable), doing so
helps with performance and diagnostics.
`openType` didn't need a locator before it was simply replacing generic
parameters with corresponding type variables but now, with opening of
pack expansions types, a locator is needed for pack expansion variables.
A pack expansion type variable gets bound to its original pattern
type when solver can infer a contextual type for it. This makes
sure that pack expansion types are always matched via `matchTypes`
without `simplifyType` involvement which can expand them prematurely.
Models `PackExpansionType` as a type variable that can only
bind to `PackExpansionType` and `expansion of` constraint that
connects expansion variable to its pattern, shape types.
Introduce `ConstraintSystem::recordTypeVariablesAsHoles` as a
standard way to record that unbound type variables found in a
type are holes in the given constraint system.
* Use fancy arrows (`→`) because they are distinct from and shorter than `->`,
and fancier.
* We have two ways of demarcating locators: `@ <locator>` and `[[<locator>]];`.
Stick to the first, which is shorter and clearer.
* 'attempting type variable' → 'attempting binding'. *Bindings* are attempted,
not type variables.
* `considering ->` → `considering:`. I think a colon is semantically more fit
and makes things easier to read if the considered constraint has arrows in its
description or types. It’s also shorter this way.
element environments.
This allows the constraint system to ensure that for a given pack expansion locator,
the given shape class is always the same when requesting the element environment.
If the shape class differs, it means there's a same-shape requirement failure, which
will be diagnosed via the ShapeOf constraint simplification.
Generic arguments types are not always resolved enough to enable
aggregated mismatch fixes, which means that the solver should be
able to handle standalone generic argument matching constraints
and create a fix per mismatch location to coalesce them during
diagnostics.
Resolves: rdar://106054263
