Move len-checker helpers to utils file

Author: ethan-leba

pylint/checkers/refactoring/len_checker.py

@@ -2,36 +2,12 @@
 
 # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 # For details: https://github.com/PyCQA/pylint/blob/master/COPYING
-from typing import Optional
-
 import astroid
 
 from pylint import checkers, interfaces
 from pylint.checkers import utils
 
 
-def _is_call_of_name(node: astroid.node_classes.NodeNG, name: str) -> bool:
-    """Checks if node is a function call with the given name"""
-    return (
-        isinstance(node, astroid.Call)
-        and isinstance(node.func, astroid.Name)
-        and node.func.name == name
-    )
-
-
-def _is_test_condition(
-    node: astroid.node_classes.NodeNG,
-    parent: Optional[astroid.node_classes.NodeNG] = None,
-) -> bool:
-    """Returns true if the given node is being tested for truthiness"""
-    parent = parent or node.parent
-    if isinstance(parent, (astroid.While, astroid.If, astroid.IfExp, astroid.Assert)):
-        return node is parent.test or parent.test.parent_of(node)
-    if isinstance(parent, astroid.Comprehension):
-        return node in parent.ifs
-    return _is_call_of_name(parent, "bool") and parent.parent_of(node)
-
-
 class LenChecker(checkers.BaseChecker):
     """Checks for incorrect usage of len() inside conditions.
     Pep8 states:
@@ -79,7 +55,7 @@ def visit_call(self, node):
         # a len(S) call is used inside a test condition
         # could be if, while, assert or if expression statement
         # e.g. `if len(S):`
-        if _is_call_of_name(node, "len"):
+        if utils.is_call_of_name(node, "len"):
             # the len() call could also be nested together with other
             # boolean operations, e.g. `if z or len(x):`
             parent = node.parent
@@ -88,7 +64,7 @@ def visit_call(self, node):
 
             # we're finally out of any nested boolean operations so check if
             # this len() call is part of a test condition
-            if _is_test_condition(node, parent):
+            if utils.is_test_condition(node, parent):
                 self.add_message("len-as-condition", node=node)
 
     @utils.check_messages("len-as-condition")
@@ -99,6 +75,6 @@ def visit_unaryop(self, node):
         if (
             isinstance(node, astroid.UnaryOp)
             and node.op == "not"
-            and _is_call_of_name(node.operand, "len")
+            and utils.is_call_of_name(node.operand, "len")
         ):
             self.add_message("len-as-condition", node=node)

pylint/checkers/refactoring/refactoring_checker.py

@@ -16,7 +16,6 @@
 from pylint import checkers, interfaces
 from pylint import utils as lint_utils
 from pylint.checkers import utils
-from pylint.checkers.refactoring.len_checker import _is_test_condition
 from pylint.checkers.utils import node_frame_class
 
 KNOWN_INFINITE_ITERATORS = {"itertools.count"}
@@ -1003,7 +1002,7 @@ def _check_simplifiable_condition(self, node):
 
         Variables will not be simplified, even in the value can be inferred,
         and expressions like '3 + 4' will remain expanded."""
-        if not _is_test_condition(node):
+        if not utils.is_test_condition(node):
             return
 
         self._can_simplify_bool_op = False

pylint/checkers/utils.py

@@ -1314,3 +1314,25 @@ def is_protocol_class(cls: astroid.node_classes.NodeNG) -> bool:
     # Use .ancestors() since not all protocol classes can have
     # their mro deduced.
     return any(parent.qname() in TYPING_PROTOCOLS for parent in cls.ancestors())
+
+
+def is_call_of_name(node: astroid.node_classes.NodeNG, name: str) -> bool:
+    """Checks if node is a function call with the given name"""
+    return (
+        isinstance(node, astroid.Call)
+        and isinstance(node.func, astroid.Name)
+        and node.func.name == name
+    )
+
+
+def is_test_condition(
+    node: astroid.node_classes.NodeNG,
+    parent: Optional[astroid.node_classes.NodeNG] = None,
+) -> bool:
+    """Returns true if the given node is being tested for truthiness"""
+    parent = parent or node.parent
+    if isinstance(parent, (astroid.While, astroid.If, astroid.IfExp, astroid.Assert)):
+        return node is parent.test or parent.test.parent_of(node)
+    if isinstance(parent, astroid.Comprehension):
+        return node in parent.ifs
+    return is_call_of_name(parent, "bool") and parent.parent_of(node)