no-eq-null.jsā¢1.12 kB
/**
* @fileoverview Rule to flag comparisons to null without a type-checking
* operator.
* @author Ian Christian Myers
*/
"use strict";
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
type: "suggestion",
docs: {
description:
"Disallow `null` comparisons without type-checking operators",
recommended: false,
url: "https://eslint.org/docs/latest/rules/no-eq-null",
},
schema: [],
messages: {
unexpected: "Use '===' to compare with null.",
},
},
create(context) {
return {
BinaryExpression(node) {
const badOperator =
node.operator === "==" || node.operator === "!=";
if (
(node.right.type === "Literal" &&
node.right.raw === "null" &&
badOperator) ||
(node.left.type === "Literal" &&
node.left.raw === "null" &&
badOperator)
) {
context.report({ node, messageId: "unexpected" });
}
},
};
},
};