The impact should be very high because the whole body is skipped
if the builder does not support some of the operations, otherwise
the fix would interfere with result builders that do support
operations but have syntactic issues in the body.
Resolves: rdar://89880662
In cases like:
```
if (...) {
<body>
} else if (...) {
<body>
} else if (...) {
<body>
}
```
Each branch should end with `buildOptional` wrapping `buildEither`
because there is no covering unconditional `else` in the sequence:
```
var $__builder: <<Type>>
if (...) {
$__builder = buildOptional(.some(buildEither(...)))
} else {
if (...) {
$__builder = buildOptional(.some(buildEither(...)))
} else {
if (...) {
$__builder = buildOptional(.some(buildEither(...)))
} else {
$__builder = buildOptional(.none)
}
}
}
```
Resolves: rdar://104345754
Placeholder variable that represents result of `if` should be placed
at the beginning of the statement, same goes for `Optional(.some(...))`
that wraps the expression in "then" branch.
Resolves: https://github.com/apple/swift/issues/62848
Inject `buildBlock` call into `return`, `buildFinalResult`, and
`build{Optional, Either}` to take advantage of contextual information
and maintain compatibility with current inference behavior.
`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
Split out brace element handling for a couple of
walkers into a new function. The diff for this is
best viewed without whitespace changes. This
should be NFC.
Result builders would be able to declare:
- uninitialized variables
- variables with property wrappers (with and without explicit initializer)
- default initializable variables i.e. `var x: Int?`
- computed variables
- `lazy` variables
If `CompletionContextFinder` fails to find a `CompletionNode`, skip
trying to filter and add solutions to the completion callback. This
prevents an assertion/crash in `filterSolutionsForCodeCompletion` which
assumes `CompletionNode` is non-null (either an expression or keypath).
Resolves rdar://99966094.
Replace the use of bool and pointer returns for
`walkToXXXPre`/`walkToXXXPost`, and instead use
explicit actions such as `Action::Continue(E)`,
`Action::SkipChildren(E)`, and `Action::Stop()`.
There are also conditional variants, e.g
`Action::SkipChildrenIf`, `Action::VisitChildrenIf`,
and `Action::StopIf`.
There is still more work that can be done here, in
particular:
- SourceEntityWalker still needs to be migrated.
- Some uses of `return false` in pre-visitation
methods can likely now be replaced by
`Action::Stop`.
- We still use bool and pointer returns internally
within the ASTWalker traversal, which could likely
be improved.
But I'm leaving those as future work for now as
this patch is already large enough.
Introduce the compiler directive `#_hasSymbol` which will be used to detect whether weakly linked symbols are present at runtime. It is intended for use in combination with `@_weakLinked import` or `-weak-link-at-target`.
```
if #_hasSymbol(foo(_:)) {
foo(42)
}
```
Parsing only; SILGen is coming in a later commit.
Resolves rdar://99342017
Fixes a bug in `buildOptional` injection for `if else` branches
without unconditional `else` which leaves type-join with just `.some(...)`
and results in optionality mismatch if `buildOptional` don't not produce
an optional type.
function body, map the result builder type into context.
This was already done for inferred result builder attributes; now,
the constraint system will map the builder type into context for all
result builder attributes applied to computed properties/functions.
If `buildBlock` is also unavailable, or the
builder itself is unavailable, continue to solve
using `buildPartialBlock` to get better
diagnostics.
This behavior technically differs from what is
specified in SE-0348, but only affects the invalid
case where no builder methods are available to use.
In particular, this improves diagnostics for
RegexComponentBuilder when the deployment target
is too low. Previously we would try to solve using
`buildBlock` (as `buildPartialBlock` is unavailable),
but RegexComponentBuilder only defines `buildBlock`
for the empty body case, leading to unhelpful
diagnostics that ultimately preferred not to use
the result builder at all.
rdar://97533700
Previously we would cache the result of the first
query, with any further query of
`ResultBuilder::supports` ignoring the
`checkAvailability` parameter. Separate out the
availability checking such that we compute the
information up front, and adjust the result
depending on `checkAvailability`.
With the change to include `SmallVector.h` directly in `LLVM.h` rather
than forward declaring in the only case it matters (ie. Clang <= 5),
these fixes are no longer needed. Since defaulted version is preferred
when there's no better choice (which is presumably the case if that's
how they were originally added), use it instead. Some uses were instead
changed to add `llvm::` so remove that too.
Since result builder is just an AST transformation, the result
of a successful transform could be cache and reused with a different
`$__builderSelf` type.
The transform changes closure body into a multi-statement closure
with all of the implicit result builder calls and type-checks it
like a regular closure.
There are a couple of result builder specific changes mentioned below,
otherwise the logic to generate constraints and apply solutions is
unchanged:
- Placeholder variable: A variable declaration that doesn't have a
type deduced and infers it from its first use. If such a variable
has an initializer, it would be type-checked during solution application.
- TypeJoinExpr - an implicit expression that refers to a "join" variable
and a set of expressions that should all produce the same type that
becomes a type of a "join" variable.
Previously for-in target was actually an expression target, which means
certain type-checking behavior. These changes make it a standalone target
with custom behavior which would allow solver to introduce implicit
`makeIterator` and `next` calls and move some logic from SILGen.
For all of the `build*` calls, let's use a special variable declaration
`$builderSelf` which refers to a type of the builder used. This allows
us to remove hacks related to use of `TypeExpr`. Reference to `$builderSelf`
is replaced with `TypeExpr` during solution application when the builder
type is completely resolved.
We record fixes while solving normal expressions for code completion and we should do the same when solving result builders if we are reporting the solutions to completion callbacks.
