Remove docs and code associated with the removed W0623 (redefine-in-handler) checker (#4543)

* remove docs and code associated with the removed W0623 checker

Author: lorena-b

CONTRIBUTORS.txt

@@ -501,3 +501,5 @@ contributors:
 * Fabian Damken: contributor
 
 * Markus Siebenhaar: contributor
+
+* Lorena Buciu (lorena-b): contributor

pylint/checkers/base.py

@@ -1986,8 +1986,6 @@ def visit_assignname(self, node):
                     utils.safe_infer(assign_type.value), astroid.Const
                 ):
                     self._check_name("const", node.name, node)
-            elif isinstance(assign_type, astroid.ExceptHandler):
-                self._check_name("variable", node.name, node)
             elif isinstance(
                 assign_type, astroid.AnnAssign
             ) and utils.is_assign_name_annotated_with(node, "Final"):
@@ -2062,10 +2060,6 @@ def _should_exempt_from_invalid_name(node):
                     return True
             return False
 
-        if utils.is_inside_except(node):
-            clobbering, _ = utils.clobber_in_except(node)
-            if clobbering:
-                return
         if self._name_allowed_by_regex(name=name):
             return
         if self._name_disallowed_by_regex(name=name):

pylint/checkers/utils.py

@@ -277,15 +277,6 @@ class InferredTypeError(Exception):
     pass
 
 
-def is_inside_except(node):
-    """Returns true if node is inside the name of an except handler."""
-    current = node
-    while current and not isinstance(current.parent, astroid.ExceptHandler):
-        current = current.parent
-
-    return current and current is current.parent.name
-
-
 def is_inside_lambda(node: astroid.node_classes.NodeNG) -> bool:
     """Return true if given node is inside lambda"""
     parent = node.parent
@@ -307,31 +298,6 @@ def get_all_elements(
         yield node
 
 
-def clobber_in_except(
-    node: astroid.node_classes.NodeNG,
-) -> Tuple[bool, Optional[Tuple[str, str]]]:
-    """Checks if an assignment node in an except handler clobbers an existing
-    variable.
-
-    Returns (True, args for W0623) if assignment clobbers an existing variable,
-    (False, None) otherwise.
-    """
-    if isinstance(node, astroid.AssignAttr):
-        return True, (node.attrname, f"object {node.expr.as_string()!r}")
-    if isinstance(node, astroid.AssignName):
-        name = node.name
-        if is_builtin(name):
-            return True, (name, "builtins")
-
-        stmts = node.lookup(name)[1]
-        if stmts and not isinstance(
-            stmts[0].assign_type(),
-            (astroid.Assign, astroid.AugAssign, astroid.ExceptHandler),
-        ):
-            return True, (name, "outer scope (line %s)" % stmts[0].fromlineno)
-    return False, None
-
-
 def is_super(node: astroid.node_classes.NodeNG) -> bool:
     """return True if the node is referencing the "super" builtin function"""
     if getattr(node, "name", None) == "super" and node.root().name == BUILTINS_NAME:

pylint/checkers/variables.py

@@ -457,11 +457,6 @@ def _has_locals_call_after_node(stmt, scope):
         "redefined-builtin",
         "Used when a variable or function override a built-in.",
     ),
-    "W0623": (
-        "Redefining name %r from %s in exception handler",
-        "redefine-in-handler",
-        "Used when an exception handler assigns the exception to an existing name",
-    ),
     "W0631": (
         "Using possibly undefined loop variable %r",
         "undefined-loop-variable",
@@ -731,7 +726,7 @@ def visit_module(self, node):
         self._postponed_evaluation_enabled = is_postponed_evaluation_enabled(node)
 
         for name, stmts in node.locals.items():
-            if utils.is_builtin(name) and not utils.is_inside_except(stmts[0]):
+            if utils.is_builtin(name):
                 if self._should_ignore_redefined_builtin(stmts[0]) or name == "__doc__":
                     continue
                 self.add_message("redefined-builtin", args=name, node=stmts[0])
@@ -819,8 +814,6 @@ def visit_functiondef(self, node):
             return
         globs = node.root().globals
         for name, stmt in node.items():
-            if utils.is_inside_except(stmt):
-                continue
             if name in globs and not isinstance(stmt, astroid.Global):
                 definition = globs[name][0]
                 if (

tests/functional/r/redefined_argument_from_local.py

@@ -1,5 +1,5 @@
 # pylint: disable=missing-docstring, unused-variable, unused-argument
-# pylint: disable=redefined-outer-name, invalid-name, redefine-in-handler
+# pylint: disable=redefined-outer-name, invalid-name
 
 def test_redefined_in_with(name):
     with open('something') as name: # [redefined-argument-from-local]