Attribute macros are expanded during AttachedSemanticAttrsRequest. This
change invokves the expansion, but it does nothing with the result yet.
The next step is to parse back in the attribute list, type check it, and
return the resulting attributes back to the request to add to the semantic
attribute list.
Accessor macros are attached macros (written with attribute syntax)
that can generate accessors for a property or subscript. Recognize
custom attributes that are accessor macros when written on a storage
declaration, and expand those macros.
This is very much a work in progress, and the result of the expansion
isn't yet parsed or wired into the AST.
Add support for freestanding declaration macros.
- Parse `@declaration` attribute.
- Type check and expand `MacroExpansionDecl`.
Known issues:
- Generic macros are not yet handled.
- Expansion does not work when the parent decl context is `BraceStmt`. Need to parse freestanding declaration macro expansions in `BraceStmt` as `MacroExpansionDecl`, and add expanded decls to name lookup.
With macro expansions, and really any code generation that produces
proper source locations, the parent source file of a declaration
context will be a generated source file rather than the source file
near the top of the declaration-context stack. Adjust the
implementation of `getParentSourceFile()` to return that innermost
source file by doing location-based lookup.
"Relink" the folded syntax node back into the primary syntax node. When
we do this, we get consistent source locations that do not require any
adjustment.
Test this by adding a Fix-It to the silly AddBlocker macro, replacing
the `+` with a `-`.
Implement an ASTGen operation to bridge swift-syntax diagnostics, as
produced by the parser, operator folding, and macros, over to the C++
diagnostic engine infrastructure. Use this to wire up macro expansion
diagnostics.
The API provided by macro evaluation has changed a bit. Adapt ASTGen to
the new API, and use this as an opportunity to start moving more tests
to using the shared libraries built into the toolchain.
