/** * @fileoverview Rule to disallow use of Object.prototype builtins on objects * @author Andrew Levine */ "use strict"; //------------------------------------------------------------------------------ // Requirements //------------------------------------------------------------------------------ const astUtils = require("./utils/ast-utils"); //------------------------------------------------------------------------------ // Rule Definition //------------------------------------------------------------------------------ module.exports = { meta: { type: "problem", docs: { description: "disallow calling some `Object.prototype` methods directly on objects", category: "Possible Errors", recommended: true, url: "https://eslint.org/docs/rules/no-prototype-builtins" }, schema: [], messages: { prototypeBuildIn: "Do not access Object.prototype method '{{prop}}' from target object." } }, create(context) { const DISALLOWED_PROPS = [ "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable" ]; /** * Reports if a disallowed property is used in a CallExpression * @param {ASTNode} node The CallExpression node. * @returns {void} */ function disallowBuiltIns(node) { const callee = astUtils.skipChainExpression(node.callee); if (callee.type !== "MemberExpression") { return; } const propName = astUtils.getStaticPropertyName(callee); if (propName !== null && DISALLOWED_PROPS.indexOf(propName) > -1) { context.report({ messageId: "prototypeBuildIn", loc: callee.property.loc, data: { prop: propName }, node }); } } return { CallExpression: disallowBuiltIns }; } };