Files
react-native-devtools-frontend/node_modules/eslint/lib/rules/no-compare-neg-zero.js
T
Tim van der Lippe 0ceb465d1c Update ESLint and plugin packages
R=jacktfranklin@chromium.org

Bug: none
Change-Id: If1b2420ba6e1c100c3d6b2013815ff1a555ea987
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/3369367
Auto-Submit: Tim Van der Lippe <tvanderlippe@chromium.org>
Reviewed-by: Jack Franklin <jacktfranklin@chromium.org>
Commit-Queue: Jack Franklin <jacktfranklin@chromium.org>
2022-01-06 15:06:40 +00:00

61 lines
1.9 KiB
JavaScript

/**
* @fileoverview The rule should warn against code that tries to compare against -0.
* @author Aladdin-ADD <hh_2013@foxmail.com>
*/
"use strict";
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../shared/types').Rule} */
module.exports = {
meta: {
type: "problem",
docs: {
description: "disallow comparing against -0",
recommended: true,
url: "https://eslint.org/docs/rules/no-compare-neg-zero"
},
fixable: null,
schema: [],
messages: {
unexpected: "Do not use the '{{operator}}' operator to compare against -0."
}
},
create(context) {
//--------------------------------------------------------------------------
// Helpers
//--------------------------------------------------------------------------
/**
* Checks a given node is -0
* @param {ASTNode} node A node to check.
* @returns {boolean} `true` if the node is -0.
*/
function isNegZero(node) {
return node.type === "UnaryExpression" && node.operator === "-" && node.argument.type === "Literal" && node.argument.value === 0;
}
const OPERATORS_TO_CHECK = new Set([">", ">=", "<", "<=", "==", "===", "!=", "!=="]);
return {
BinaryExpression(node) {
if (OPERATORS_TO_CHECK.has(node.operator)) {
if (isNegZero(node.left) || isNegZero(node.right)) {
context.report({
node,
messageId: "unexpected",
data: { operator: node.operator }
});
}
}
}
};
}
};