Merge pull request #5305 from tk0miya/5211_autodoc_for_partial_functions

Fix #5211: autodoc: No docs generated for functools.partial functions

5 files changed, 101 insertions, 19 deletions

diff --git a/CHANGES b/CHANGES
index 58431cee8..e17247476 100644
--- a/CHANGES
+++ b/CHANGES
@@ -29,6 +29,7 @@ Bugs fixed
 * #5280: autodoc: Fix wrong type annotations for complex typing
 * autodoc: Optional types are wrongly rendered
 * #5291: autodoc crashed by ForwardRef types
+* #5211: autodoc: No docs generated for functools.partial functions
 * #5298: imgmath: math_number_all causes equations to have two numbers in html
 
 Testing
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 058fd7765..7d34e185d 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -32,7 +32,7 @@ from sphinx.util import rpartition, force_decode
 from sphinx.util.docstrings import prepare_docstring
 from sphinx.util.inspect import Signature, isdescriptor, safe_getmembers, \
     safe_getattr, object_description, is_builtin_class_method, \
-    isenumattribute, isclassmethod, isstaticmethod, getdoc
+    isenumattribute, isclassmethod, isstaticmethod, isfunction, isbuiltin, ispartial, getdoc
 
 if False:
     # For type annotation
@@ -399,7 +399,9 @@ class Documenter(object):
             return True
 
         modname = self.get_attr(self.object, '__module__', None)
-        if modname and modname != self.modname:
+        if ispartial(self.object) and modname == '_functools':  # for pypy
+            return True
+        elif modname and modname != self.modname:
             return False
         return True
 
@@ -473,9 +475,8 @@ class Documenter(object):
     def get_doc(self, encoding=None, ignore=1):
         # type: (unicode, int) -> List[List[unicode]]
         """Decode and return lines of the docstring(s) for the object."""
-        docstring = self.get_attr(self.object, '__doc__', None)
-        if docstring is None and self.env.config.autodoc_inherit_docstrings:
-            docstring = getdoc(self.object)
+        docstring = getdoc(self.object, self.get_attr,
+                           self.env.config.autodoc_inherit_docstrings)
         # make sure we have Unicode docstrings, then sanitize and split
         # into lines
         if isinstance(docstring, text_type):
@@ -599,9 +600,7 @@ class Documenter(object):
             # if isattr is True, the member is documented as an attribute
             isattr = False
 
-            doc = self.get_attr(member, '__doc__', None)
-            if doc is None and self.env.config.autodoc_inherit_docstrings:
-                doc = getdoc(member)
+            doc = getdoc(member, self.get_attr, self.env.config.autodoc_inherit_docstrings)
 
             # if the member __doc__ is the same as self's __doc__, it's just
             # inherited and therefore not the member's doc
@@ -1022,12 +1021,11 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
     @classmethod
     def can_document_member(cls, member, membername, isattr, parent):
         # type: (Any, unicode, bool, Any) -> bool
-        return inspect.isfunction(member) or inspect.isbuiltin(member)
+        return isfunction(member) or isbuiltin(member)
 
     def format_args(self):
         # type: () -> unicode
-        if inspect.isbuiltin(self.object) or \
-                inspect.ismethoddescriptor(self.object):
+        if isbuiltin(self.object) or inspect.ismethoddescriptor(self.object):
             # cannot introspect arguments of a C function or method
             return None
         try:
@@ -1095,7 +1093,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         # __init__ written in C?
         if initmeth is None or \
                 is_builtin_class_method(self.object, '__init__') or \
-                not(inspect.ismethod(initmeth) or inspect.isfunction(initmeth)):
+                not(inspect.ismethod(initmeth) or isfunction(initmeth)):
             return None
         try:
             return Signature(initmeth, bound_method=True, has_retval=False).format_args()
@@ -1304,8 +1302,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
 
     def format_args(self):
         # type: () -> unicode
-        if inspect.isbuiltin(self.object) or \
-                inspect.ismethoddescriptor(self.object):
+        if isbuiltin(self.object) or inspect.ismethoddescriptor(self.object):
             # can never get arguments of a C function or method
             return None
         if isstaticmethod(self.object, cls=self.parent, name=self.object_name):
@@ -1336,7 +1333,7 @@ class AttributeDocumenter(DocstringStripSignatureMixin, ClassLevelDocumenter):
 
     @staticmethod
     def is_function_or_method(obj):
-        return inspect.isfunction(obj) or inspect.isbuiltin(obj) or inspect.ismethod(obj)
+        return isfunction(obj) or isbuiltin(obj) or inspect.ismethod(obj)
 
     @classmethod
     def can_document_member(cls, member, membername, isattr, parent):
diff --git a/sphinx/util/inspect.py b/sphinx/util/inspect.py
index 64e93f267..3b5d48e2a 100644
--- a/sphinx/util/inspect.py
+++ b/sphinx/util/inspect.py
@@ -15,6 +15,7 @@ import re
 import sys
 import typing
 from collections import OrderedDict
+from functools import partial
 
 from six import PY2, PY3, StringIO, binary_type, string_types, itervalues
 from six.moves import builtins
@@ -99,8 +100,6 @@ if PY3:
                                    kwonlyargs, kwdefaults, annotations)
 
 else:  # 2.7
-    from functools import partial
-
     def getargspec(func):
         # type: (Any) -> Any
         """Like inspect.getargspec but supports functools.partial as well."""
@@ -155,6 +154,12 @@ def isenumattribute(x):
     return isinstance(x, enum.Enum)
 
 
+def ispartial(obj):
+    # type: (Any) -> bool
+    """Check if the object is partial."""
+    return isinstance(obj, partial)
+
+
 def isclassmethod(obj):
     # type: (Any) -> bool
     """Check if the object is classmethod."""
@@ -198,6 +203,18 @@ def isdescriptor(x):
     return False
 
 
+def isfunction(obj):
+    # type: (Any) -> bool
+    """Check if the object is function."""
+    return inspect.isfunction(obj) or ispartial(obj) and inspect.isfunction(obj.func)
+
+
+def isbuiltin(obj):
+    # type: (Any) -> bool
+    """Check if the object is builtin."""
+    return inspect.isbuiltin(obj) or ispartial(obj) and inspect.isbuiltin(obj.func)
+
+
 def safe_getattr(obj, name, *defargs):
     # type: (Any, unicode, unicode) -> object
     """A getattr() that turns all exceptions into AttributeErrors."""
@@ -601,7 +618,7 @@ class Signature(object):
 
 
 if sys.version_info >= (3, 5):
-    getdoc = inspect.getdoc
+    _getdoc = inspect.getdoc
 else:
     # code copied from the inspect.py module of the standard library
     # of Python 3.5
@@ -679,7 +696,7 @@ else:
                 return doc
         return None
 
-    def getdoc(object):
+    def _getdoc(object):
         """Get the documentation string for an object.
 
         All tabs are expanded to spaces.  To clean up docstrings that are
@@ -697,3 +714,21 @@ else:
         if not isinstance(doc, str):
             return None
         return inspect.cleandoc(doc)
+
+
+def getdoc(obj, attrgetter=safe_getattr, allow_inherited=False):
+    # type: (Any, Callable, bool) -> unicode
+    """Get the docstring for the object.
+
+    This tries to obtain the docstring for some kind of objects additionally:
+
+    * partial functions
+    * inherited docstring
+    """
+    doc = attrgetter(obj, '__doc__', None)
+    if ispartial(obj) and doc == obj.__class__.__doc__:
+        return getdoc(obj.func)
+    elif doc is None and allow_inherited:
+        doc = _getdoc(obj)
+
+    return doc
diff --git a/tests/roots/test-ext-autodoc/target/partialfunction.py b/tests/roots/test-ext-autodoc/target/partialfunction.py
new file mode 100644
index 000000000..727a62680
--- /dev/null
+++ b/tests/roots/test-ext-autodoc/target/partialfunction.py
@@ -0,0 +1,11 @@
+from functools import partial
+
+
+def func1():
+    """docstring of func1"""
+    pass
+
+
+func2 = partial(func1)
+func3 = partial(func1)
+func3.__doc__ = "docstring of func3"
diff --git a/tests/test_autodoc.py b/tests/test_autodoc.py
index 53d8a1e14..97e03c886 100644
--- a/tests/test_autodoc.py
+++ b/tests/test_autodoc.py
@@ -912,6 +912,44 @@ def test_generate():
                            'module', 'autodoc_missing_imports')
 
 
+@pytest.mark.usefixtures('setup_test')
+def test_partialfunction():
+    def call_autodoc(objtype, name):
+        inst = app.registry.documenters[objtype](directive, name)
+        inst.generate()
+        result = list(directive.result)
+        del directive.result[:]
+        return result
+
+    options.members = ALL
+    #options.undoc_members = True
+    expected = [
+        '',
+        '.. py:module:: target.partialfunction',
+        '',
+        '',
+        '.. py:function:: func1()',
+        '   :module: target.partialfunction',
+        '',
+        '   docstring of func1',
+        '   ',
+        '',
+        '.. py:function:: func2()',
+        '   :module: target.partialfunction',
+        '',
+        '   docstring of func1',
+        '   ',
+        '',
+        '.. py:function:: func3()',
+        '   :module: target.partialfunction',
+        '',
+        '   docstring of func3',
+        '   '
+    ]
+
+    assert call_autodoc('module', 'target.partialfunction') == expected
+
+
 @pytest.mark.skipif(sys.version_info < (3, 4),
                     reason='functools.partialmethod is available on py34 or above')
 @pytest.mark.usefixtures('setup_test')