Make iscoroutinefunction, isgeneratorfunction and isasyncgenfunction work with partial

Author: pablogsal

Lib/inspect.py

@@ -173,25 +173,35 @@ def isgeneratorfunction(object):
 
     Generator function objects provide the same attributes as functions.
     See help(isfunction) for a list of attributes."""
-    return bool((isfunction(object) or ismethod(object)) and
+    is_generator_function = bool((isfunction(object) or ismethod(object)) and
                 object.__code__.co_flags & CO_GENERATOR)
+    is_partial_generator = bool((isinstance(object, functools.partial) and
+                object.func.__code__.co_flags & CO_GENERATOR))
+    return is_generator_function or is_partial_generator
 
 def iscoroutinefunction(object):
     """Return true if the object is a coroutine function.
 
     Coroutine functions are defined with "async def" syntax.
     """
-    return bool((isfunction(object) or ismethod(object)) and
-                object.__code__.co_flags & CO_COROUTINE)
+    is_coroutine_function = bool(((isfunction(object) or ismethod(object)) and
+                object.__code__.co_flags & CO_COROUTINE))
+    is_partial_coroutine = bool((isinstance(object, functools.partial) and
+                object.func.__code__.co_flags & CO_COROUTINE))
+    return is_coroutine_function or is_partial_coroutine
 
 def isasyncgenfunction(object):
     """Return true if the object is an asynchronous generator function.
 
     Asynchronous generator functions are defined with "async def"
     syntax and have "yield" expressions in their body.
     """
-    return bool((isfunction(object) or ismethod(object)) and
+    is_async_gen_function = bool((isfunction(object) or ismethod(object)) and
                 object.__code__.co_flags & CO_ASYNC_GENERATOR)
+    is_partial_async_gen = bool((isinstance(object, functools.partial) and
+                object.func.__code__.co_flags & CO_ASYNC_GENERATOR))
+    return is_async_gen_function or is_partial_async_gen
+
 
 def isasyncgen(object):
     """Return true if the object is an asynchronous generator."""

Lib/test/test_inspect.py

@@ -166,26 +166,46 @@ def test_excluding_predicates(self):
             self.assertFalse(inspect.ismemberdescriptor(datetime.timedelta.days))
 
     def test_iscoroutine(self):
+        async_gen_coro = async_generator_function_example(1)
         gen_coro = gen_coroutine_function_example(1)
         coro = coroutine_function_example(1)
 
         self.assertFalse(
             inspect.iscoroutinefunction(gen_coroutine_function_example))
+        self.assertFalse(
+            inspect.iscoroutinefunction(
+                functools.partial(gen_coroutine_function_example)))
         self.assertFalse(inspect.iscoroutine(gen_coro))
 
         self.assertTrue(
             inspect.isgeneratorfunction(gen_coroutine_function_example))
+        self.assertTrue(
+            inspect.isgeneratorfunction(
+                functools.partial(gen_coroutine_function_example)))
         self.assertTrue(inspect.isgenerator(gen_coro))
 
         self.assertTrue(
             inspect.iscoroutinefunction(coroutine_function_example))
+        self.assertTrue(
+            inspect.iscoroutinefunction(
+                functools.partial(coroutine_function_example)))
         self.assertTrue(inspect.iscoroutine(coro))
 
         self.assertFalse(
             inspect.isgeneratorfunction(coroutine_function_example))
+        self.assertFalse(
+            inspect.isgeneratorfunction(
+                functools.partial(coroutine_function_example)))
         self.assertFalse(inspect.isgenerator(coro))
 
-        coro.close(); gen_coro.close() # silence warnings
+        self.assertTrue(
+            inspect.isasyncgenfunction(async_generator_function_example))
+        self.assertTrue(
+            inspect.isasyncgenfunction(
+                functools.partial(async_generator_function_example)))
+        self.assertTrue(inspect.isasyncgen(async_gen_coro))
+
+        coro.close(); gen_coro.close(); # silence warnings
 
     def test_isawaitable(self):
         def gen(): yield

Misc/NEWS.d/next/Library/2018-10-15-23-10-41.bpo-34890.77E770.rst

@@ -0,0 +1,3 @@
+Make :func:`inspect.iscoroutinefunction`,
+:func:`inspect.isgeneratorfunction` and :func:`inspect.isasyncgenfunction`
+work with :func:`functools.partial`. Patch by Pablo Galindo.