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.
Try to impose a simple structure that splits performing actions from the
pre and post-pipeline conditions. Wherever actions would take more than
a simple return, split them into functions. Refine functions that
perform effects to return status codes when they fail. Finally,
delineate functions that need semantic analysis from those that do not.
Overall this should be NFC.
This makes it easier to specify OptionSet arguments.
Also modify appropriate uses of ModuleDecl::ImportFilter to take
advantage of the new constructor.
This is an attribute that gets put on an import in library FooKit to
keep it from being a requirement to import FooKit. It's not checked at
all, meaning that in this form it is up to the author of FooKit to
make sure nothing in its API or ABI depends on the implementation-only
dependency. There's also no debugging support here (debugging FooKit
/should/ import the implementation-only dependency if it's present).
The goal is to get to a point where it /can/ be checked, i.e. FooKit
developers are prevented from writing code that would rely on FooKit's
implementation-only dependency being present when compiling clients of
FooKit. But right now it's not.
rdar://problem/48985979
...in preparation for me adding a third kind of import, making the
existing "All" kind a problem. NFC, except that I did rewrite the
ClangModuleUnit implementation of getImportedModules to be simpler!
This is purely designed to cheaply compute dependency graphs between
modules, and thus only lists the top-level names (i.e. not submodules)
and doesn't do any form of semantic analysis.
