Changelog

Unreleased

Moved away from function pointer tables for loading PyAwaitable--everything is now vendored upon installation.
Improved performance with compiler optimizations.
PyAwaitable_ prefixes are now required, and the old pyawaitable_* functions have been removed.
The warning emitted when a PyAwaitable object is not awaited is now a ResourceWarning (was a RuntimeWarning).
PyAwaitable_AddAwait now raises a ValueError if the passed object is NULL or self, and also now raises a TypeError if the passed object is not a coroutine.
Breaking Change: PyAwaitable_Init no longer takes a module object.
Breaking Change: Renamed awaitcallback to PyAwaitable_Callback
Breaking Change: Renamed awaitcallback_err to PyAwaitable_Error
Breaking Change: Renamed defercallback to PyAwaitable_Defer

Significantly reduced awaitable object size by dynamically allocating it.
Reduced memory footprint by removing preallocated awaitable objects.
Objects returned by a PyAwaitable object's __await__ are now garbage collected (i.e., they don't leak with rare circular references).
Removed limit on number of stored callbacks or values.
Switched some user-error messages to RuntimeError instead of SystemError.
Added PyAwaitable_DeferAwait for executing code without a coroutine when the awaitable object is called by the event loop.

Changed error message when attempting to await a non-awaitable object (i.e., it has no __await__).
Fixed coroutine iterator reference leak.
Fixed reference leak in error callbacks.
Fixed early exit of pyawaitable_unpack_arb if a NULL value was saved.
Added integer value saving and unpacking (pyawaitable_save_int and pyawaitable_unpack_int).
Callbacks are now preallocated for better performance.
Fixed reference leak in the coroutine send() method.