Make provided/implementedBy and adapter registries respect super().issue11

The query functions now start by looking at the next class in the MRO (interfaces directly provided by the underlying object are not found).

Adapter registries automatically pick up providedBy change to start finding the correct implementations of adapters, but to make that really useful they needed to change to unpack super() arguments and pass __self__ to the factory.

Fixes #11

Unfortunately, this makes PyPy unable to build the C extensions.

Additional crash-safety for adapter lookup.

Make the C functions get the cache only after resolving the
``required`` into a tuple, in case of side-effects like...clearing the
cache. This could lead to the ``cache`` object being deallocated
before we used it.

Drop the ``tuplefy`` function in favor of a direct call to
``PySequence_Tuple``. It's what the ``tuple`` constructor would do
anyway and saves a few steps.

Make sure that getting ``providedBy(super())`` and
``implementedBy(super())`` have no side effects.

1 files changed, 5 insertions, 3 deletions

diff --git a/setup.py b/setup.py
index b5e87a8..9b8b4b8 100644
--- a/setup.py
+++ b/setup.py
@@ -69,10 +69,12 @@ codeoptimization = [
 ]
 
 is_jython = 'java' in sys.platform
+is_pypy = hasattr(sys, 'pypy_version_info')
 
-# Jython cannot build the C optimizations. Everywhere else,
-# including PyPy, defer the decision to runtime.
-if is_jython:
+# Jython cannot build the C optimizations. Nor, as of 7.3, can PyPy (
+# it doesn't have PySuper_Type) Everywhere else, defer the decision to
+# runtime.
+if is_jython or is_pypy:
     ext_modules = []
 else:
     ext_modules = codeoptimization