* Narrow allowance of 3+ components numeric literal to condition part of the
directive.
* Allow 3+ components in '#if' directive in decl list position as well.
We used to drop the entire generic parameter list if one of the
entries failed to parse. This caused a problem where the generic
parameters were still available for name lookup, so they had
to be special-cased since there's no generic environment set up
in this case.
Now, keep the parts of the generic parameter list around that
parsed successfully.
When I first made the change, almost a hundred crashers regressed;
now all the underlying issues have been fixed.
The result is that in addition to removing a crappy hack we get
some more mileage out of the compiler_crashers, because stuff like
this now builds a generic environment:
class S<T{...}
`1 { }` was parsed as a call expression with a trailing closure. This made the diagnostics for `var x = 1 { get { ... } }` extremely bad. Resolves SR-3671.
Add diagnostics to fix decls with consecutive identifiers. This applies to
types, properties, variables, and enum cases. The diagnostic adds a camel-cased option if it is different than the first option.
https://bugs.swift.org/browse/SR-3599
Add a diagnostic to remove the name of an initializer, deinitializer, or subscript. The identifier token is consumed and skipped to prevent the parser from emitting additional error messages.
Add tests to verify that the name is removed from initializers, deinitializers, and subscripts declared with a name.
Parsing declaration list (e.g. member list of nominal decl) is very
different from comma separated list, because it's elements are separated with
new-line or semi-colon. There's no good reason to consolidate them.
Also, declaration list in 'extension' or inside of decl '#if' didn't
emit diagnostics for consecutive declarations on a line.
class C {
#if true
var value: Int = 42 func foo() {}
#endif
}
extension C {
func bar() {} subscript(i: Int) -> Int {
return 24
}
}
This change consolidates declaration list parsing for
members of nominal decls, extensions, and inside of '#if'.
In addition, removed unnecessary property 'TrailingSemiLoc' from decl.
* Pack the bits for IfConfigDecls into Decl
* Don't open symbols into a module when evaluating canImport statements
The module loaders now have API to check whether a given module can be
imported without importing the referenced module. This provides a
significant speed boost to condition resolution and no longer
introduces symbols from the referenced module into the current context
without the user explicitly requesting it.
The definition of ‘canImport’ does not necessarily mean that a full
import without error is possible, merely that the path to the import is
visible to the compiler and the module is loadable in some form or
another.
Note that this means this check is insufficient to guarantee that you
are on one platform or another. For those kinds of checks, use
‘os(OSNAME)’.
`type(of:)` has behavior whose type isn't directly representable in Swift's type system, since it produces both concrete and existential metatypes. In Swift 3 we put in a parser hack to turn `type(of: <expr>)` into a DynamicTypeExpr, but this effectively made `type(of:)` a reserved name. It's a bit more principled to put `Swift.type(of:)` on the same level as other declarations, even with its special-case type system behavior, and we can do this by special-casing the type system we produce during overload resolution if `Swift.type(of:)` shows up in an overload set. This also lays groundwork for handling other declarations we want to ostensibly behave like normal declarations but with otherwise inexpressible types, viz. `withoutActuallyEscaping` from SE-0110.
Being lazy here just means we don’t validate the entire if
configuration. We need to be able to emit diagnostics even in
condition clauses with indeterminate expressions.
This completely removes Parse’s ability to make any judgement calls
about compilation conditions, instead the parser-relevant parts of
‘evaluateConditionalCompilationExpr’ have been moved into
‘classifyConditionalCompilationExpr’ where they exist to make sure only
decls that we want to parse actually parse later.
The condition-evaluation parts have been moved into NameBinding in the
form of a Walker that evaluates and collapses IfConfigs. This walker
is meant as an homage to PlaygroundLogger. It should probably be
factored out into a common walker at some point in the future.
Instead of the simple "expected identifier in declaration", the error will now read "keyword '%' cannot be used as an identifier here", and will be accompanied by a note suggesting escaping the keyword with backticks, as well as a fixit.
https://bugs.swift.org/browse/SR-3167
* Removed `parseConstructorArguments()`, unified with
`parseSingleParameterClause()`.
* Use `parseSingleParameterClause()` from `parseFunctionSignature()`, so
that we can share the recovery code.
* Removed `isFirstParameterClause` parameter from `mapParsedParameters`,
because it's predictable from `paramContext`.
parseBraceItems() has specific logic for pasing conditional compilation blocks.
Withoutout that, decralations in the block cannot be propagated to outside.
For instance:
FOO: #if true
func foo() {}
#endif
foo() // error: use of unresolved identifier 'foo'
RFC 2279 states that, in UTF-8:
"The octet values FE and FF never appear."
RFC 3629 states that, in UTF-8:
"The octet values C0, C1, F5 to FF never appear."
Generalize the check to advance past invalid starting bytes for
a UTF-8 sequence to fix a crash in the lexer.
