All but 7 tests now passing. Those 7 tests either do not refer to these circumstances or do not seem to pass even when modified to accept type specifications.
Skipping type-checking the body when the preamble fails to type-check
seems to be more of a historical artifact than intentional behavior.
Certain elements of the body may still get type-checked through
request evaluation, and as such may introduce autoclosures that won't
be properly contextualized.
Make sure we continue type-checking the body even if the preamble
fails. We already invalidate any variables bound in the element
pattern, so downstream type-checking should be able to handle it
just fine. This ensures autoclosures get contextualized, and that
we're still able to provide semantic diagnostics for other issues in
the body.
rdar://136500008
Some editors use diagnostics from SourceKit to replace build issues. This causes issues if the diagnostics from SourceKit are formatted differently than the build issues. Make sure they are rendered the same way, removing most uses of `DiagnosticsEditorMode`.
To do so, always emit the `add stubs for conformance` note (which previously was only emitted in editor mode) and remove all `; add <something>` suffixes from notes that state which requirements are missing.
rdar://129283608
If both sides of an `OptionalObject` constraint are un-inferred, their
binding sets need to correctly reflect adjacency - a type variable
that represents optional would get "object" as an adjacency through
its potential binding (the binding is - "object" wrapped in a single
level of optional) and "object" type variable needs to get its parent
optional type variable added to its adjacency list explicitly.
Without this it would be possible to prematurely pick "object" before
its parent optional type variable.
Resolves: https://github.com/apple/swift/issues/73207
Resolves: rdar://126960579
Type-checker separates `where` clause from `for-in` statement's pattern/sequence
in closure contexts which works as a natural barrier for inference, but
for-in statements in i.e. function bodies still type-check all of the for-in
statement components together, so we need to make sure that where clause
cannot be used to infer a type of the pattern before its sequence expression.
Resolves: rdar://117220710
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.
Emulate previous `for-in` type-checking behavior where sequence
was type-checked separately from `.next()` call which, in turn,
was injected only during SIL generation.
Current approach to generate an implicit variable for `$generator`
and use it as a base to `.next()` call didn't account for the fact
that it allows the solver to rank result of `<sequence>.makeIterator()`
together with result of `next()`. This is logically incorrect because
`<sequence>.makeIterator()` represents initializer of `$generator`
which is separate from `$generator.next()` expression albeit type-checked
together.
Resolves: https://github.com/apple/swift/issues/59522
Instead of asking SILGen to build calls to `makeIterator` and
`$generator.next()`, let's synthesize and type-check them
together with the rest of for-in preamble. This greatly simplifies
interaction between Sema and SILGen for for-in statements.
The following regression test added for this feature is not passing:
Swift(linux-x86_64) :: decl/protocol/protocols_with_self_or_assoc_reqs_executable.swift
with a compiler crash happening during SILFunctionTransform "Devirtualizer".
Reverting to unblock CI.
This reverts commit f96057e260, reversing
changes made to 3fc18f3603.
Instead of requiring sub-classes of `ContextualMismatch` to implement
`diagnoseForAmbiguity` let's implement it directly on `ContextualMismatch`
itself and check whether all of the aggregated fixes have same types on
both sides and if so, diagnose as-if it was a single fix.
Previously we were only connecting a closure
constraint to type variables from param decls that
it referenced. This worked fine up until we
started type-checking for-in statements entirely
in the constraint system, meaning that closures
can now reference type variables from the element
pattern.
Tweak the collection logic to consider vars too.
Resolves rdar://62339835
Type on the right-hand side of the element conversion/pattern match
should be allowed to have holes to be able to diagnose failures with
structurally incompatible types.
Resolves: rdar://problem/60832876
If the type used in for-each loop doesn't conform to `Sequence`
let's not try to diagnose anything about its element since such
diagnostics would include unresolved types and actual problem
(missing conformance) would already be diagnosed.
Make TypeChecker::typeCheckPattern() return the computed type, rather
than returning an "error" flag. More importantly, make it functional,
so that it doesn't set the type it computes on the pattern.
Use UnresolvedType as a placeholder for types that need to be
inferred, rather than a null type. This allows us to produce
structural types involving types that need to be inferred.
Note that with this change as-is, we get a number of duplicated
diagnostics, because typeCheckPattern() will be called multiple times
for the same pattern and will emit some diagnostics each time. This
will be addressed in a subsequent commit.
Rather than having the type checker look for the specific witness to
next() when type checking the for-each loop, which had the effect of
devirtualizing next() even when it shouldn't be, leave the formation
of the next() reference to SILGen. There, form it as a witness
reference, so that the SIL optimizer can choose whether to
devirtualization (or not).
Introduce a new kind of constraint, the "value witness" constraint,
which captures a reference to a witness for a specific protocol
conformance. It otherwise acts like a more restricted form of a "value
member" constraint, where the specific member is known (as a
ValueDecl*) in advance.
The constraint is effectively dependent on the protocol
conformance itself; if that conformance fails, mark the type variables
in the resolved member type as "holes", so that the conformance
failure does not cascade.
Note that the resolved overload for this constraint always refers to
the requirement, rather than the witness, so we will end up recording
witness-method references in the AST rather than concrete references,
and leave it up to the optimizers to perform devirtualization. This is
demonstrated by the SIL changes needed in tests, and is part of the
wider resilience issue with conformances described by
rdar://problem/22708391.
* [TypeChecker] Enclosing stubs protocol note within editor mode
* [test] Removing note from test where there is no -diagnostics-editor-mode flag
* Formatting modified code
* [tests] Fixing tests under validation-tests
Patch up all the places that are making a syntactic judgement about the
isInvalid() bit in a ValueDecl. They may continue to use that query,
but most guard themselves on whether the interface type has been set.
This is an amalgam of simplifications to the way VarDecls are checked
and assigned interface types.
First, remove TypeCheckPattern's ability to assign the interface and
contextual types for a given var decl. Instead, replace it with the
notion of a "naming pattern". This is the pattern that semantically
binds a given VarDecl into scope, and whose type will be used to compute
the interface type. Note that not all VarDecls have a naming pattern
because they may not be canonical.
Second, remove VarDecl's separate contextual type member, and force the
contextual type to be computed the way it always was: by mapping the
interface type into the parent decl context.
Third, introduce a catch-all diagnostic to properly handle the change in
the way that circularity checking occurs. This is also motivated by
TypeCheckPattern not being principled about which parts of the AST it
chooses to invalidate, especially the parent pattern and naming patterns
for a given VarDecl. Once VarDecls are invalidated along with their
parent patterns, a large amount of this diagnostic churn can disappear.
Unfortunately, if this isn't here, we will fail to catch a number of
obviously circular cases and fail to emit a diagnostic.
Under non-editor mode, the fixit for inserting protocol stubs is associated with a note
pointing to the missing protocol member declaration which could stay in a separate file from
the conforming type, leading to the behavior of rdar://51534405. This change checks if
the fixit is in a separate file and issues another note to carry the fixit if so.
rdar://51534405
When we determine that an optional value needs to be unwrapped to make
an expression type check, use notes to provide several different
Fix-It options (with descriptions) rather than always pushing users
toward '!'. Specifically, the errors + Fix-Its now looks like this:
error: value of optional type 'X?' must be unwrapped to a value of
type 'X'
f(x)
^
note: coalesce using '??' to provide a default when the optional
value contains 'nil'
f(x)
^
?? <#default value#>
note: force-unwrap using '!' to abort execution if the optional
value contains 'nil'
f(x)
^
!
Fixes rdar://problem/42081852.
Rather than relying on the NameAliasType we get by default for references
to non-generic typealiases, use BoundNameAliasType consistently to handle
references to typealiases that are formed by the type checker.
