Each macro expansion buffer was getting parsed twice: once by
ParseSourceFileRequest (which is used by unqualified name lookup) and
once to parse the expression when type-checking the expanded macro.
This meant that the same code had two ASTs. Hilarity ensures.
Stop directly invoking the parser on macro-expanded code. Instead, go
through ParseSourceFileRequest *as is always the right way*, and dig
out the expression we want.
We need swiftsourcedocinfo for cursor info and to be able to reuse the ASTContext from code completion for cursor info, we need to also retrieve the sourcedocinfo for code completion requests.
Establish the relationship for generated sources, whether for macro
expansions or (via a small stretch) replacing function bodies with
other bodies, in the source manager itself. This makes the information
available for diagnostic rendering, and unifies a little bit of the
representation, although it isn't used for much yet.
This brings up the ability to compute cursor info results using the completion-like type checking paradigm, which an reuse ASTContexts and doesn’t need to type check the entire file.
For now, the new implementation only supports cursor info on `ValueDecl`s (not on references) because they were easiest to implement. More cursor info kinds are coming soon.
At the moment, we only run the new implementation in a verification mode: It is only invoked in assert toolchains and when run, we check that the results are equivalent to the old implementation. Once more cursor info kinds are implemented and if the SourceKit stress tester doesn’t find any verification issues, we can enable the new implementation, falling back to the old implementation if the new one didn’t produce any results.
Introduce a new source file kind to describe source files for macro
expansions, and include the macro expression that they expand. This
establishes a "parent" relationship
Also track every kind of auxiliary source file---whether for macro
expansions or other reasons---that is introduced into a module, adding
an operation that allows us to find the source file that contains a
given source location.
These libraries formed a strongly connected component in the CMake build graph. The weakest link I could find was from IDE to FrontendTool and Frontend, which was necessitated by the `CompileInstance` class (https://github.com/apple/swift/pull/40645). I moved a few files out of IDE into a new IDETools library to break the cycle.
