`module.map` as a module map name has been discouraged since 2014, and
Clang will soon warn on its usage. This patch renames all instances of
`module.map` in the Swift tests to `module.modulemap` in preparation
for this change to Clang.
rdar://106123303
Use the modern spelling for the nullability attributes in the test mock
headers. Currently, this was relying on the predefined macros from
clang to work. However, those are only available on Darwin targets.
This is needed to make the mock environments more portable.
Somehow the logic had slipped so that we were basing this decision purely
on the ImportTypeKind and not on whether the broader context is bridgeable.
This was allowing us to use bridged types when e.g. importing the results
and parameters of C function pointer types, which is really bad.
Also, when importing a reference to a typedef of block type, do not use
the typedef in a non-bridgeable context. We import typedefs of block type
as fully-bridged types, but this means that it is invalid to import a type
using the typedef in a context where the original C type must be used.
Similarly, make sure we use a properly-imported underlying type of the
typedef when the typedef itself is unavailable.
Also, extend the special behavior of block typedefs to abstract-function
typedefs, which seems to be consistent with the expected behavior of the
tests.
Finally, I changed importType to take a new Bridgeability enum instead of
a raw canFullyBridgeTypes bool. At the time, I was doing that because I
was going to make it tri-valued; that turned out to be unnecessary, but I
think it's an improvement anyway.
Block types can't be used in structs (because they're managed by ARC),
are rarely referred to by pointers, and would pretty much never be
globals. Additionally, their syntax is complicated enough that people
tend to make typedefs for them fairly frequently. We'd like to preserve
that sugar, but we don't really need to preserve the representation
when the most likely use of the block is in a bridged context (e.g. a
method parameter). In the rare case where the representation /is/
important, fall back to re-importing the underlying type.
rdar://problem/22013912
Swift SVN r30738
