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-rw-r--r--pylint/extensions/comparetozero.py95
1 files changed, 0 insertions, 95 deletions
diff --git a/pylint/extensions/comparetozero.py b/pylint/extensions/comparetozero.py
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index 116bf229a..000000000
--- a/pylint/extensions/comparetozero.py
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@@ -1,95 +0,0 @@
-# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
-# For details: https://github.com/PyCQA/pylint/blob/main/LICENSE
-# Copyright (c) https://github.com/PyCQA/pylint/blob/main/CONTRIBUTORS.txt
-
-"""Looks for comparisons to zero."""
-
-from __future__ import annotations
-
-import itertools
-from typing import TYPE_CHECKING
-
-import astroid
-from astroid import nodes
-
-from pylint import checkers
-from pylint.checkers import utils
-from pylint.interfaces import HIGH
-
-if TYPE_CHECKING:
- from pylint.lint import PyLinter
-
-
-def _is_constant_zero(node: str | nodes.NodeNG) -> bool:
- # We have to check that node.value is not False because node.value == 0 is True
- # when node.value is False
- return (
- isinstance(node, astroid.Const) and node.value == 0 and node.value is not False
- )
-
-
-class CompareToZeroChecker(checkers.BaseChecker):
- """Checks for comparisons to zero.
-
- Most of the time you should use the fact that integers with a value of 0 are false.
- An exception to this rule is when 0 is allowed in the program and has a
- different meaning than None!
- """
-
- # configuration section name
- name = "compare-to-zero"
- msgs = {
- "C2001": (
- '"%s" can be simplified to "%s" as 0 is falsey',
- "compare-to-zero",
- "Used when Pylint detects comparison to a 0 constant.",
- )
- }
-
- options = ()
-
- @utils.only_required_for_messages("compare-to-zero")
- def visit_compare(self, node: nodes.Compare) -> None:
- # pylint: disable=duplicate-code
- _operators = ["!=", "==", "is not", "is"]
- # note: astroid.Compare has the left most operand in node.left
- # while the rest are a list of tuples in node.ops
- # the format of the tuple is ('compare operator sign', node)
- # here we squash everything into `ops` to make it easier for processing later
- ops: list[tuple[str, nodes.NodeNG]] = [("", node.left)]
- ops.extend(node.ops)
- iter_ops = iter(ops)
- all_ops = list(itertools.chain(*iter_ops))
-
- for ops_idx in range(len(all_ops) - 2):
- op_1 = all_ops[ops_idx]
- op_2 = all_ops[ops_idx + 1]
- op_3 = all_ops[ops_idx + 2]
- error_detected = False
-
- # 0 ?? X
- if _is_constant_zero(op_1) and op_2 in _operators:
- error_detected = True
- op = op_3
- # X ?? 0
- elif op_2 in _operators and _is_constant_zero(op_3):
- error_detected = True
- op = op_1
-
- if error_detected:
- original = f"{op_1.as_string()} {op_2} {op_3.as_string()}"
- suggestion = (
- op.as_string()
- if op_2 in {"!=", "is not"}
- else f"not {op.as_string()}"
- )
- self.add_message(
- "compare-to-zero",
- args=(original, suggestion),
- node=node,
- confidence=HIGH,
- )
-
-
-def register(linter: PyLinter) -> None:
- linter.register_checker(CompareToZeroChecker(linter))