diff options
| -rw-r--r-- | Lib/rlcompleter.py | 10 | ||||
| -rw-r--r-- | Lib/test/test_rlcompleter.py | 32 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2021-07-27-22-11-29.bpo-44752._bvbrZ.rst | 2 |
3 files changed, 40 insertions, 4 deletions
diff --git a/Lib/rlcompleter.py b/Lib/rlcompleter.py index c06388e..34b2599 100644 --- a/Lib/rlcompleter.py +++ b/Lib/rlcompleter.py @@ -176,6 +176,16 @@ class Completer: if (word[:n] == attr and not (noprefix and word[:n+1] == noprefix)): match = "%s.%s" % (expr, word) + if isinstance(getattr(type(thisobject), word, None), + property): + # bpo-44752: thisobject.word is a method decorated by + # `@property`. What follows applies a postfix if + # thisobject.word is callable, but know we know that + # this is not callable (because it is a property). + # Also, getattr(thisobject, word) will evaluate the + # property method, which is not desirable. + matches.append(match) + continue try: val = getattr(thisobject, word) except Exception: diff --git a/Lib/test/test_rlcompleter.py b/Lib/test/test_rlcompleter.py index ee3019d..1f7a6ed 100644 --- a/Lib/test/test_rlcompleter.py +++ b/Lib/test/test_rlcompleter.py @@ -81,17 +81,41 @@ class TestRlcompleter(unittest.TestCase): if x.startswith('s')]) def test_excessive_getattr(self): - # Ensure getattr() is invoked no more than once per attribute + """Ensure getattr() is invoked no more than once per attribute""" + + # note the special case for @property methods below; that is why + # we use __dir__ and __getattr__ in class Foo to create a "magic" + # class attribute 'bar'. This forces `getattr` to call __getattr__ + # (which is doesn't necessarily do). class Foo: calls = 0 + bar = '' + def __getattribute__(self, name): + if name == 'bar': + self.calls += 1 + return None + return super().__getattribute__(name) + + f = Foo() + completer = rlcompleter.Completer(dict(f=f)) + self.assertEqual(completer.complete('f.b', 0), 'f.bar') + self.assertEqual(f.calls, 1) + + def test_property_method_not_called(self): + class Foo: + _bar = 0 + property_called = False + @property def bar(self): - self.calls += 1 - return None + self.property_called = True + return self._bar + f = Foo() completer = rlcompleter.Completer(dict(f=f)) self.assertEqual(completer.complete('f.b', 0), 'f.bar') - self.assertEqual(f.calls, 1) + self.assertFalse(f.property_called) + def test_uncreated_attr(self): # Attributes like properties and slots should be completed even when diff --git a/Misc/NEWS.d/next/Library/2021-07-27-22-11-29.bpo-44752._bvbrZ.rst b/Misc/NEWS.d/next/Library/2021-07-27-22-11-29.bpo-44752._bvbrZ.rst new file mode 100644 index 0000000..0d8a2cd --- /dev/null +++ b/Misc/NEWS.d/next/Library/2021-07-27-22-11-29.bpo-44752._bvbrZ.rst @@ -0,0 +1,2 @@ +:mod:`rcompleter` does not call :func:`getattr` on :class:`property` objects +to avoid the side-effect of evaluating the corresponding method. |