Find all the usages of `--enable-experimental-feature` or
`--enable-upcoming-feature` in the tests and replace some of the
`REQUIRES: asserts` to use `REQUIRES: swift-feature-Foo` instead, which
should correctly apply to depending on the asserts/noasserts mode of the
toolchain for each feature.
Remove some comments that talked about enabling asserts since they don't
apply anymore (but I might had miss some).
All this was done with an automated script, so some formatting weirdness
might happen, but I hope I fixed most of those.
There might be some tests that were `REQUIRES: asserts` that might run
in `noasserts` toolchains now. This will normally be because their
feature went from experimental to upcoming/base and the tests were not
updated.
The feature InternalImportsByDefault makes imports default to internal instead
of public. Applying the Swift 6 behavior of SE-0409 in Swift 5.
Let's use only that flag to track the Swift 6 behavior as well instead
of separately checking for the language version.
When using access level on imports, consider non-public imports to be
implementation details not exposed to clients. As such, a client loading
a library doesn't need to load non-public transitive dependencies.
This behave like `@_implementationOnly imports` at a module-wide level,
but it is restricted to resilient modules only. An import with any
access-level in a non-resilient module remains visible to transitive
clients.