Commit Graph

7 Commits

Author SHA1 Message Date
Serhiy Storchaka 0b40aab6f0 Issue #25280: Import trace messages emitted in verbose (-v) mode are no
longer formatted twice.
2015-10-01 11:40:22 +03:00
Yury Selivanov 5376ba9630 Issue #24400: Introduce a distinct type for 'async def' coroutines.
Summary of changes:

1. Coroutines now have a distinct, separate from generators
   type at the C level: PyGen_Type, and a new typedef PyCoroObject.
   PyCoroObject shares the initial segment of struct layout with
   PyGenObject, making it possible to reuse existing generators
   machinery.  The new type is exposed as 'types.CoroutineType'.

   As a consequence of having a new type, CO_GENERATOR flag is
   no longer applied to coroutines.

2. Having a separate type for coroutines made it possible to add
   an __await__ method to the type.  Although it is not used by the
   interpreter (see details on that below), it makes coroutines
   naturally (without using __instancecheck__) conform to
   collections.abc.Coroutine and collections.abc.Awaitable ABCs.

   [The __instancecheck__ is still used for generator-based
   coroutines, as we don't want to add __await__ for generators.]

3. Add new opcode: GET_YIELD_FROM_ITER.  The opcode is needed to
   allow passing native coroutines to the YIELD_FROM opcode.

   Before this change, 'yield from o' expression was compiled to:

      (o)
      GET_ITER
      LOAD_CONST
      YIELD_FROM

   Now, we use GET_YIELD_FROM_ITER instead of GET_ITER.

   The reason for adding a new opcode is that GET_ITER is used
   in some contexts (such as 'for .. in' loops) where passing
   a coroutine object is invalid.

4. Add two new introspection functions to the inspec module:
   getcoroutinestate(c) and getcoroutinelocals(c).

5. inspect.iscoroutine(o) is updated to test if 'o' is a native
   coroutine object.  Before this commit it used abc.Coroutine,
   and it was requested to update inspect.isgenerator(o) to use
   abc.Generator; it was decided, however, that inspect functions
   should really be tailored for checking for native types.

6. sys.set_coroutine_wrapper(w) API is updated to work with only
   native coroutines.  Since types.coroutine decorator supports
   any type of callables now, it would be confusing that it does
   not work for all types of coroutines.

7. Exceptions logic in generators C implementation was updated
   to raise clearer messages for coroutines:

   Before: TypeError("generator raised StopIteration")
   After: TypeError("coroutine raised StopIteration")
2015-06-22 12:19:30 -04:00
Benjamin Peterson ee85339cc6 in dict displays, evaluate the key before the value (closes #11205)
Patch partially by Steve Dougherty.
2015-05-28 14:30:26 -05:00
Nick Coghlan d5cacbb1d9 PEP 489: Multi-phase extension module initialization
Known limitations of the current implementation:

- documentation changes are incomplete
- there's a reference leak I haven't tracked down yet

The leak is most visible by running:

  ./python -m test -R3:3 test_importlib

However, you can also see it by running:

  ./python -X showrefcount

Importing the array or _testmultiphase modules, and
then deleting them from both sys.modules and the local
namespace shows significant increases in the total
number of active references each cycle. By contrast,
with _testcapi (which continues to use single-phase
initialisation) the global refcounts stabilise after
a couple of cycles.
2015-05-23 22:24:10 +10:00
Eric Snow 183a941bc1 Issue #24192: Fix namespace package imports. 2015-05-15 21:54:59 -06:00
Benjamin Peterson 025e9ebd0a PEP 448: additional unpacking generalizations (closes #2292)
Patch by Neil Girdhar.
2015-05-05 20:16:41 -04:00
Eric Snow 32439d6eb6 Issue #23911: Move path-based bootstrap code to a separate frozen module. 2015-05-02 19:15:18 -06:00