1  __all__ = 'iscoroutinefunction', 'iscoroutine'
       2  
       3  import collections.abc
       4  import inspect
       5  import os
       6  import sys
       7  import types
       8  
       9  
      10  def _is_debug_mode():
      11      # See: https://docs.python.org/3/library/asyncio-dev.html#asyncio-debug-mode.
      12      return sys.flags.dev_mode or (not sys.flags.ignore_environment and
      13                                    bool(os.environ.get('PYTHONASYNCIODEBUG')))
      14  
      15  
      16  # A marker for iscoroutinefunction.
      17  _is_coroutine = object()
      18  
      19  
      20  def iscoroutinefunction(func):
      21      """Return True if func is a decorated coroutine function."""
      22      return (inspect.iscoroutinefunction(func) or
      23              getattr(func, '_is_coroutine', None) is _is_coroutine)
      24  
      25  
      26  # Prioritize native coroutine check to speed-up
      27  # asyncio.iscoroutine.
      28  _COROUTINE_TYPES = (types.CoroutineType, collections.abc.Coroutine)
      29  _iscoroutine_typecache = set()
      30  
      31  
      32  def iscoroutine(obj):
      33      """Return True if obj is a coroutine object."""
      34      if type(obj) in _iscoroutine_typecache:
      35          return True
      36  
      37      if isinstance(obj, _COROUTINE_TYPES):
      38          # Just in case we don't want to cache more than 100
      39          # positive types.  That shouldn't ever happen, unless
      40          # someone stressing the system on purpose.
      41          if len(_iscoroutine_typecache) < 100:
      42              _iscoroutine_typecache.add(type(obj))
      43          return True
      44      else:
      45          return False
      46  
      47  
      48  def _format_coroutine(coro):
      49      assert iscoroutine(coro)
      50  
      51      def get_name(coro):
      52          # Coroutines compiled with Cython sometimes don't have
      53          # proper __qualname__ or __name__.  While that is a bug
      54          # in Cython, asyncio shouldn't crash with an AttributeError
      55          # in its __repr__ functions.
      56          if hasattr(coro, '__qualname__') and coro.__qualname__:
      57              coro_name = coro.__qualname__
      58          elif hasattr(coro, '__name__') and coro.__name__:
      59              coro_name = coro.__name__
      60          else:
      61              # Stop masking Cython bugs, expose them in a friendly way.
      62              coro_name = f'<{type(coro).__name__} without __name__>'
      63          return f'{coro_name}()'
      64  
      65      def is_running(coro):
      66          try:
      67              return coro.cr_running
      68          except AttributeError:
      69              try:
      70                  return coro.gi_running
      71              except AttributeError:
      72                  return False
      73  
      74      coro_code = None
      75      if hasattr(coro, 'cr_code') and coro.cr_code:
      76          coro_code = coro.cr_code
      77      elif hasattr(coro, 'gi_code') and coro.gi_code:
      78          coro_code = coro.gi_code
      79  
      80      coro_name = get_name(coro)
      81  
      82      if not coro_code:
      83          # Built-in types might not have __qualname__ or __name__.
      84          if is_running(coro):
      85              return f'{coro_name} running'
      86          else:
      87              return coro_name
      88  
      89      coro_frame = None
      90      if hasattr(coro, 'gi_frame') and coro.gi_frame:
      91          coro_frame = coro.gi_frame
      92      elif hasattr(coro, 'cr_frame') and coro.cr_frame:
      93          coro_frame = coro.cr_frame
      94  
      95      # If Cython's coroutine has a fake code object without proper
      96      # co_filename -- expose that.
      97      filename = coro_code.co_filename or '<empty co_filename>'
      98  
      99      lineno = 0
     100  
     101      if coro_frame is not None:
     102          lineno = coro_frame.f_lineno
     103          coro_repr = f'{coro_name} running at {filename}:{lineno}'
     104  
     105      else:
     106          lineno = coro_code.co_firstlineno
     107          coro_repr = f'{coro_name} done, defined at {filename}:{lineno}'
     108  
     109      return coro_repr