8th day of python challenges 111-117

venv/lib/python3.6/site-packages/pylint/test/functional/slots_checks.py

@@ -0,0 +1,85 @@
+""" Checks that classes uses valid __slots__ """
+
+# pylint: disable=too-few-public-methods, missing-docstring, no-absolute-import, useless-object-inheritance
+# pylint: disable=using-constant-test, wrong-import-position, no-else-return
+from collections import deque
+
+def func():
+    if True:
+        return ("a", "b", "c")
+    else:
+        return [str(var) for var in range(3)]
+
+
+class NotIterable(object):
+    def __iter_(self):
+        """ do nothing """
+
+class Good(object):
+    __slots__ = ()
+
+class SecondGood(object):
+    __slots__ = []
+
+class ThirdGood(object):
+    __slots__ = ['a']
+
+class FourthGood(object):
+    __slots__ = ('a%s' % i for i in range(10))
+
+class FifthGood(object):
+    __slots__ = deque(["a", "b", "c"])
+
+class SixthGood(object):
+    __slots__ = {"a": "b", "c": "d"}
+
+class Bad(object): # [invalid-slots]
+    __slots__ = list
+
+class SecondBad(object):  # [invalid-slots]
+    __slots__ = 1
+
+class ThirdBad(object):
+    __slots__ = ('a', 2)  # [invalid-slots-object]
+
+class FourthBad(object):  # [invalid-slots]
+    __slots__ = NotIterable()
+
+class FifthBad(object):
+    __slots__ = ("a", "b", "")  # [invalid-slots-object]
+
+class SixthBad(object):  # [single-string-used-for-slots]
+    __slots__ = "a"
+
+class SeventhBad(object):  # [single-string-used-for-slots]
+    __slots__ = ('foo')
+
+class EighthBad(object):  # [single-string-used-for-slots]
+    __slots__ = deque.__name__
+
+class PotentiallyGood(object):
+    __slots__ = func()
+
+class PotentiallySecondGood(object):
+    __slots__ = ('a', deque.__name__)
+
+
+import six
+
+
+class Metaclass(type):
+
+    def __iter__(cls):
+        for value in range(10):
+            yield str(value)
+
+
+@six.add_metaclass(Metaclass)
+class IterableClass(object):
+    pass
+
+class PotentiallyThirdGood(object):
+    __slots__ = IterableClass
+
+class PotentiallyFourthGood(object):
+    __slots__ = Good.__slots__