This started out as a crash, where an expression macro could not be
defined in terms of one of the builtin macros (e.g., `#line`), because
we were expecting a macro expansion expression but didn't get one.
Easy fix.
However, this uncovered a second bug, which is that we couldn't handle
an expression macro expansino to `#line`. This is because we were
parsing the macro expansion buffer as "top level items", which treats
`#line` at the start of a line as a deprecated alias of
`#sourceLocation`. Switch over to parsing a single expression in these
contexts, and fix up an issue where `#isolation` didn't even have that
expression.
Fixes rdar://139372780.
* Make ExportedSourceFile hold any Syntax as the root node
* Move `ExportedSourceFileRequest::evaluate()` to `ParseRequests.cpp`
* Pass the decl context and `GeneatedSourceFileInfo::Kind` to
`swift_ASTGen_parseSourceFile()` to customize the parsing
* Make `ExportedSourceFile` to hold an arbitrary Syntax node
* Move round-trip checking into `ExportedSourceFileRequest::evaluate()`
* Split `parseSourceFileViaASTGen` completely from C++ parsing logic
(in `ParseSourceFileRequest::evaluate()`)
* Remove 'ParserDiagnostics' experimental feature: Now that we have
ParserASTGen mode which includes the swift-syntax parser diagnostics.
Mangling and looking up the opaque result type decl
for serialized decls is a fairly expensive
operation. Instead, fallthrough to the request
which will have a cached value set by deserialization.
This shaves ~30ms off the cached completion for:
```swift
import SwiftUI
struct V: View {
var body: some View {
Table(#^CC^#
}
}
```
Treat `@_unavailableInEmbedded` as if it were `@available(Embedded,
unavailable)` and apply platform compatibility logic in the availability
checker. Revert back to disallowing calls to universally unavailable functions
(`@available(*, unavailable)`) in all contexts.
This achieves the same as clang's `-fdebug-info-for-profiling`, which
emits DWARF discriminators to aid in narrowing-down which basic block
corresponds to a particular instruction address. This is particularly
useful for sampling-based profiling.
rdar://135443278
Availability checking for types was only suppressed when the immediate context
for the use of the type was explicitly marked unavailable. Availability is
lexical so the checking should be suppressed in the entire scope instead.
Add flag `-load-resolved-plugin` to load macro plugin, which provides a
pre-resolved entry into PluginLoader so the plugins can be loaded based
on module name without searching the file system. The option is mainly
intended to be used by explicitly module build and the flag is supplied
by dependency scanner.
Today ParenType is used:
1. As the type of ParenExpr
2. As the payload type of an unlabeled single
associated value enum case (and the type of
ParenPattern).
3. As the type for an `(X)` TypeRepr
For 1, this leads to some odd behavior, e.g the
type of `(5.0 * 5).squareRoot()` is `(Double)`. For
2, we should be checking the arity of the enum case
constructor parameters and the presence of
ParenPattern respectively. Eventually we ought to
consider replacing Paren/TuplePattern with a
PatternList node, similar to ArgumentList.
3 is one case where it could be argued that there's
some utility in preserving the sugar of the type
that the user wrote. However it's really not clear
to me that this is particularly desirable since a
bunch of diagnostic logic is already stripping
ParenTypes. In cases where we care about how the
type was written in source, we really ought to be
consulting the TypeRepr.
This problem comes up with the following example:
```swift
class A {
var description = ""
}
class B {
let a = A()
func b() {
let asdf = ""
Task { @MainActor in
a.description = asdf // Sending 'asdf' risks causing data races
}
}
}
```
The specific issue is that the closure we generate actually includes an
implicit(any) parameter at the SIL level which occurs after the callee operand
but before the captures. This caused the captured variable index from the AST
and the one we compute from the partial_apply to differ by 1. So we need to
subtract 1 in such a case. That is why we used to print 'asdf' instead of 'a'
above.
DISCUSSION: This shows an interesting difference between SIL applied arg indices
and AST indices. SIL applied arg indices would include the implicit(any)
parameter since it is a parameter in the SIL function type. In contrast, this
doesn't show up in the formal AST parameters or captures. To make it easier to
reason about this, I added a new API to ApplySite called
ApplySite::getASTAppliedArgIndex and added large comments to
getASTAppliedArgIndex and getAppliedArgIndex that explains the issue.
rdar://136593706
https://github.com/swiftlang/swift/issues/76648
