1 files changed, 63 insertions, 0 deletions
diff --git a/tests/functional/u/unnecessary/unnecessary_not.py b/tests/functional/u/unnecessary/unnecessary_not.py
new file mode 100644
index 000000000..97acecd73
--- /dev/null
+++ b/tests/functional/u/unnecessary/unnecessary_not.py
@@ -0,0 +1,63 @@
+"""Check exceeding negations in boolean expressions trigger warnings"""
+
+# pylint: disable=singleton-comparison,too-many-branches,too-few-public-methods,undefined-variable
+# pylint: disable=literal-comparison, comparison-with-itself, useless-object-inheritance
+def unneeded_not():
+    """This is not ok
+    """
+    bool_var = True
+    someint = 2
+    if not not bool_var:  # [unneeded-not]
+        pass
+    if not someint == 1:  # [unneeded-not]
+        pass
+    if not someint != 1:  # [unneeded-not]
+        pass
+    if not someint < 1:  # [unneeded-not]
+        pass
+    if not someint > 1:  # [unneeded-not]
+        pass
+    if not someint <= 1:  # [unneeded-not]
+        pass
+    if not someint >= 1:  # [unneeded-not]
+        pass
+    if not not someint:  # [unneeded-not]
+        pass
+    if not bool_var == True:  # [unneeded-not]
+        pass
+    if not bool_var == False:  # [unneeded-not]
+        pass
+    if not bool_var != True:  # [unneeded-not]
+        pass
+    if not True == True:  # [unneeded-not]
+        pass
+    if not 2 in [3, 4]:  # [unneeded-not]
+        pass
+    if not someint is 'test':  # [unneeded-not]
+        pass
+
+
+def tolerated_statements():
+    """This is ok"""
+    bool_var = True
+    someint = 2
+    if not(bool_var == False and someint == 1):
+        pass
+    if 2 not in [3, 4]:
+        pass
+    if not someint == bool_var == 2:
+        pass
+    if not 2 <= someint < 3 < 4:
+        pass
+    if not set('bar') <= set('foobaz'):
+        pass
+    if not set(something) <= 3:
+        pass
+    if not frozenset(something) <= 3:
+        pass
+
+
+class Klass(object):
+    """This is also ok"""
+    def __ne__(self, other):
+        return not self == other