Peer macro produce declarations that are semantically alongside the
declaration to which the macro is attached. However, the source
location used for constructing the scope tree was based on the
attribute itself, which meant it was inside the scope of the
declaration to which the macro was attached. This lead to incorrect
unqualified name lookup; in the example that's now a test case, this
meant that the `Self` of the protocol to which the macro was attached
was visible from within the peer declaration. Hilarity (in the form of
a type checker crash) ensued.
Fix the location used for constructing the scope tree of peer macros to
be right after the attached declaration. Fixes rdar://107228586.
Ensure that name lookup triggers the expansion of member macros on
extensions, so we can find those names. And fix a bug that caused
expansion of member macros to crash.
Teach ASTScope to create child nodes for each of the arguments of a
macro expansion declaration, so that we can perform name lookup into
them. Otherwise, we cannot have nontrivial closures in arguments to a
macro expansion declaration.
Fixes rdar://107388151.
In preparation for supporting macros that are defined in terms of other
macros, adopt macro definition checking provided by the
`MacroDeclSyntax.checkDefinition` operation (implemented in
swift-syntax). Use this in lieu of the checking on the C++ side.
This required me to finally fix an issue with the source ranges for
Fix-Its, where we were replacing the leading/trailing trivia of nodes
along with the node itself, even though that's incorrect: we should
only replce the node itself, and there are other Fix-It kinds for
replacing leading or trailing trivia.
Allow freestanding macros to be used at top-level.
- Parse top-level `#…` as `MacroExpansionDecl` when we are not in scripting mode.
- Add macro expansion decls to the source lookup cache with name-driven lazy expansion. Not supporting arbitrary name yet.
- Experimental support for script mode and brace-level declaration macro expansions: When type-checking a `MacroExpansionExpr`, assign it a substitute `MacroExpansionDecl` if the macro reference resolves to a declaration macro. This doesn’t work quite fully yet and will be enabled in a future fix.
When we form an extension for a conformance macro, make sure to
register that extension as being part of the nominal type to which the
conformance macro is attached. This ensures that the conformance is
seen everywhere. Crucially, this ensures that that protocol
conformance table handles conformances that are implied by the
conformance macro. For example, a conformance macro that introduces a
`Hashable` conformance will also imply an `Equatable` conformance;
that wasn't happening before this change.
This is needed to make the `OptionSet` macro work fully.
Provide ASTWalker with a customization point to specify whether to
check macro arguments (which are type checked but never emitted), the
macro expansion (which is the result of applying the macro and is
actually emitted into the source), or both. Provide answers for the
~115 different ASTWalker visitors throughout the code base.
Fixes rdar://104042945, which concerns checking of effects in
macro arguments---which we shouldn't do.
The macro role argument presented an opportunity for callers to accidentally
invoke this request twice for the same macro with slightly different macro
roles passed in, which resulted in re-typechecking the macro arguments.
Instead, derive the corresponding macro roles from the macro reference syntax.
Global peer macro expansions are not injected into the AST. Instead, they
are visited as "auxiliary declarations" when needed, such as in the decl
checker and during SILGen. This is the same mechanism used for local property
wrappers and local lazy variables.
- Use the name lookup table instead of adding members from a macro expansion to the parent decl context.
- Require declaration macros to specify introduced names and used the declared names to guide macro expansions lazily.
Rather than trying to patch up the "basic" macro expansion context
that comes from the swift-syntax package, implement our own based
on the new SourceManager. Fixes the `location(of:)` operation.
Errors that were thrown out of a macro implementation were being
emitted and then lost. The result of this is a SILGen assertion later
on, if there were no other errors in the code.
Make sure we properly emit these diagnostics through the source
manager, which required fixing an issue in the offset computation used
for diagnostics.
Use the name mangling scheme we've devised for macro expansions to
back the implementation of the macro expansion context's
`getUniqueName` operation. This way, we guarantee that the names
provided by macro expansions don't conflict, as well as making them
demangleable so we can determine what introduced the names.
Add SourceManager that can keep track of multiple source file syntax
nodes along with their external representations. The source manager can
emit diagnostics into any of those files, including tracking any
explicitly "detached" syntax nodes used for macro expansion.
Make sure we detach syntax nodes before passing them to macro
implementations, so they cannot see more of the source file than they
are permitted. We hadn't been doing this before (by accident), and
doing so motivated the introduction of the SourceManager.
Additionally, perform operator folding on macro arguments as part of
detaching them. Macro clients shouldn't have to do this, and moreover,
when clients do this, they lose the ability to easily emit diagnostics
on the now-folded nodes.
scopes.
ASTScope lookup can no longer assume that all scopes are within the same source
file. Scope trees can now contain scopes that are in macro expansion buffers, which
live in different source files with independent source ranges from the root of a
given scope tree. To handle this when searching for a scope containing a given source
location, ASTScope lookup needs to walk up the chain of macro expansion buffers to find
the lowest common buffer in which to compare source locations.
This fixes a number of issues with unqualified lookup into and from within macro-expanded
code.
