Rename unneeded-not to unnecessary-negation for clarity (#8846)

Co-authored-by: Jiang <[email protected]>

Author: gracejiang16

doc/data/messages/u/unnecessary-negation/bad.py

@@ -0,0 +1,7 @@
+if not not input():  # [unnecessary-negation]
+    pass
+
+a = 3
+b = 10
+if not a > b:  # [unnecessary-negation]
+    pass

doc/data/messages/u/unnecessary-negation/good.py

@@ -0,0 +1,7 @@
+if input():
+    pass
+
+a = 3
+b = 10
+if a <= b:
+    pass

doc/data/messages/u/unneeded-not/bad.py

@@ -0,0 +1,3 @@
+Renamed the "unneeded-not" error into "unnecessary_negation" to be clearer.
+
+Closes #8789

doc/data/messages/u/unneeded-not/good.py

@@ -17,10 +17,12 @@ class NotChecker(checkers.BaseChecker):
     """
 
     msgs = {
-        "C0113": (
+        "C0117": (
             'Consider changing "%s" to "%s"',
-            "unneeded-not",
-            "Used when a boolean expression contains an unneeded negation.",
+            "unnecessary-negation",
+            "Used when a boolean expression contains an unneeded negation, "
+            "e.g. when two negation operators cancel each other out.",
+            {"old_names": [("C0113", "unneeded-not")]},
         )
     }
     name = "refactoring"
@@ -40,15 +42,15 @@ class NotChecker(checkers.BaseChecker):
     # 'builtins' py3, '__builtin__' py2
     skipped_classnames = [f"builtins.{qname}" for qname in ("set", "frozenset")]
 
-    @utils.only_required_for_messages("unneeded-not")
+    @utils.only_required_for_messages("unnecessary-negation")
     def visit_unaryop(self, node: nodes.UnaryOp) -> None:
         if node.op != "not":
             return
         operand = node.operand
 
         if isinstance(operand, nodes.UnaryOp) and operand.op == "not":
             self.add_message(
-                "unneeded-not",
+                "unnecessary-negation",
                 node=node,
                 args=(node.as_string(), operand.operand.as_string()),
             )
@@ -78,5 +80,5 @@ def visit_unaryop(self, node: nodes.UnaryOp) -> None:
                 f"{left.as_string()} {self.reverse_op[operator]} {right.as_string()}"
             )
             self.add_message(
-                "unneeded-not", node=node, args=(node.as_string(), suggestion)
+                "unnecessary-negation", node=node, args=(node.as_string(), suggestion)
             )

doc/whatsnew/fragments/8789.other

@@ -2,38 +2,38 @@
 
 # pylint: disable=singleton-comparison,too-many-branches,too-few-public-methods,undefined-variable
 # pylint: disable=literal-comparison, comparison-with-itself, comparison-of-constants
-def unneeded_not():
+def unnecessary_negation():
     """This is not ok
     """
     bool_var = True
     someint = 2
-    if not not bool_var:  # [unneeded-not]
+    if not not bool_var:  # [unnecessary-negation]
         pass
-    if not someint == 1:  # [unneeded-not]
+    if not someint == 1:  # [unnecessary-negation]
         pass
-    if not someint != 1:  # [unneeded-not]
+    if not someint != 1:  # [unnecessary-negation]
         pass
-    if not someint < 1:  # [unneeded-not]
+    if not someint < 1:  # [unnecessary-negation]
         pass
-    if not someint > 1:  # [unneeded-not]
+    if not someint > 1:  # [unnecessary-negation]
         pass
-    if not someint <= 1:  # [unneeded-not]
+    if not someint <= 1:  # [unnecessary-negation]
         pass
-    if not someint >= 1:  # [unneeded-not]
+    if not someint >= 1:  # [unnecessary-negation]
         pass
-    if not not someint:  # [unneeded-not]
+    if not not someint:  # [unnecessary-negation]
         pass
-    if not bool_var == True:  # [unneeded-not]
+    if not bool_var == True:  # [unnecessary-negation]
         pass
-    if not bool_var == False:  # [unneeded-not]
+    if not bool_var == False:  # [unnecessary-negation]
         pass
-    if not bool_var != True:  # [unneeded-not]
+    if not bool_var != True:  # [unnecessary-negation]
         pass
-    if not True == True:  # [unneeded-not]
+    if not True == True:  # [unnecessary-negation]
         pass
-    if not 2 in [3, 4]:  # [unneeded-not]
+    if not 2 in [3, 4]:  # [unnecessary-negation]
         pass
-    if not someint is 'test':  # [unneeded-not]
+    if not someint == 'test':  # [unnecessary-negation]
         pass
 
 

pylint/checkers/refactoring/not_checker.py

@@ -0,0 +1,14 @@
+unnecessary-negation:10:7:10:23:unnecessary_negation:"Consider changing ""not not bool_var"" to ""bool_var""":UNDEFINED
+unnecessary-negation:12:7:12:23:unnecessary_negation:"Consider changing ""not someint == 1"" to ""someint != 1""":UNDEFINED
+unnecessary-negation:14:7:14:23:unnecessary_negation:"Consider changing ""not someint != 1"" to ""someint == 1""":UNDEFINED
+unnecessary-negation:16:7:16:22:unnecessary_negation:"Consider changing ""not someint < 1"" to ""someint >= 1""":UNDEFINED
+unnecessary-negation:18:7:18:22:unnecessary_negation:"Consider changing ""not someint > 1"" to ""someint <= 1""":UNDEFINED
+unnecessary-negation:20:7:20:23:unnecessary_negation:"Consider changing ""not someint <= 1"" to ""someint > 1""":UNDEFINED
+unnecessary-negation:22:7:22:23:unnecessary_negation:"Consider changing ""not someint >= 1"" to ""someint < 1""":UNDEFINED
+unnecessary-negation:24:7:24:22:unnecessary_negation:"Consider changing ""not not someint"" to ""someint""":UNDEFINED
+unnecessary-negation:26:7:26:27:unnecessary_negation:"Consider changing ""not bool_var == True"" to ""bool_var != True""":UNDEFINED
+unnecessary-negation:28:7:28:28:unnecessary_negation:"Consider changing ""not bool_var == False"" to ""bool_var != False""":UNDEFINED
+unnecessary-negation:30:7:30:27:unnecessary_negation:"Consider changing ""not bool_var != True"" to ""bool_var == True""":UNDEFINED
+unnecessary-negation:32:7:32:23:unnecessary_negation:"Consider changing ""not True == True"" to ""True != True""":UNDEFINED
+unnecessary-negation:34:7:34:22:unnecessary_negation:"Consider changing ""not 2 in [3, 4]"" to ""2 not in [3, 4]""":UNDEFINED
+unnecessary-negation:36:7:36:28:unnecessary_negation:"Consider changing ""not someint == 'test'"" to ""someint != 'test'""":UNDEFINED