gh-121025: Improve partialmethod.__repr__ (GH-121033)

It no longer contains redundant commas and spaces.

Author: picnixz

Lib/functools.py

@@ -373,15 +373,13 @@ def __init__(self, func, /, *args, **keywords):
             self.keywords = keywords
 
     def __repr__(self):
-        args = ", ".join(map(repr, self.args))
-        keywords = ", ".join("{}={!r}".format(k, v)
-                                 for k, v in self.keywords.items())
-        format_string = "{module}.{cls}({func}, {args}, {keywords})"
-        return format_string.format(module=self.__class__.__module__,
-                                    cls=self.__class__.__qualname__,
-                                    func=self.func,
-                                    args=args,
-                                    keywords=keywords)
+        cls = type(self)
+        module = cls.__module__
+        qualname = cls.__qualname__
+        args = [repr(self.func)]
+        args.extend(map(repr, self.args))
+        args.extend(f"{k}={v!r}" for k, v in self.keywords.items())
+        return f"{module}.{qualname}({', '.join(args)})"
 
     def _make_unbound_method(self):
         def _method(cls_or_self, /, *args, **keywords):

Lib/test/test_asyncio/test_events.py

@@ -2348,7 +2348,7 @@ def test_handle_repr(self):
         h = asyncio.Handle(cb, (), self.loop)
 
         cb_regex = r'<function HandleTests.test_handle_repr .*>'
-        cb_regex = fr'functools.partialmethod\({cb_regex}, , \)\(\)'
+        cb_regex = fr'functools.partialmethod\({cb_regex}\)\(\)'
         regex = fr'^<Handle {cb_regex} at {re.escape(filename)}:{lineno}>$'
         self.assertRegex(repr(h), regex)
 

Lib/test/test_functools.py

@@ -569,6 +569,14 @@ class B:
                 method = functools.partialmethod(func=capture, a=1)
 
     def test_repr(self):
+        self.assertEqual(repr(vars(self.A)['nothing']),
+                         'functools.partialmethod({})'.format(capture))
+        self.assertEqual(repr(vars(self.A)['positional']),
+                         'functools.partialmethod({}, 1)'.format(capture))
+        self.assertEqual(repr(vars(self.A)['keywords']),
+                         'functools.partialmethod({}, a=2)'.format(capture))
+        self.assertEqual(repr(vars(self.A)['spec_keywords']),
+                         'functools.partialmethod({}, self=1, func=2)'.format(capture))
         self.assertEqual(repr(vars(self.A)['both']),
                          'functools.partialmethod({}, 3, b=4)'.format(capture))
 

Misc/NEWS.d/next/Library/2024-06-26-10-13-40.gh-issue-121025.M-XXlV.rst

@@ -0,0 +1,2 @@
+Improve the :meth:`~object.__repr__` of :class:`functools.partialmethod`.
+Patch by Bénédikt Tran.