Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
To help consolidate our various types describing imports, this commit moves the following types and methods to Import.h:
* ImplicitImports
* ImplicitStdlibKind
* ImplicitImportInfo
* ModuleDecl::ImportedModule
* ModuleDecl::OrderImportedModules (as ImportedModule::Order)
* ModuleDecl::removeDuplicateImports() (as ImportedModule::removeDuplicates())
* SourceFile::ImportFlags
* SourceFile::ImportOptions
* SourceFile::ImportedModuleDesc
This commit is large and intentionally kept mechanical—nothing interesting to see here.
Re-implement operator and precedencegroup decl
lookup to use `namelookup::getAllImports` and
existing decl shadowing logic. This allows us to
find operator decls through `@_exported` imports,
prefer operator decls defined in the same module
over imported decls, and fixes a couple of other
subtle issues.
Because this new implementation is technically
source breaking, as we can find multiple results
where we used to only find one result, it's placed
behind the new Frontend flag
`-enable-new-operator-lookup` (with the aim of
enabling it by default when we get a new language
mode).
However the new logic will always be used if the
result is unambiguous. This means that e.g
`@_exported` operators will be instantly available
as long as there's only one candidate. If multiple
candidates are found, we fall back to the old
logic.
Resolves SR-12132.
Resolves rdar://59198796.
