2025-04-19 23:12:19 -04:00

142 lines
4.1 KiB
JavaScript

/**
* @fileoverview Rule to flag use of implied eval via setTimeout and setInterval
* @author James Allardice
*/
'use strict';
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const astUtils = require('./utils/ast-utils');
const { getStaticValue } = require('@eslint-community/eslint-utils');
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
type: 'suggestion',
docs: {
description: 'Disallow the use of `eval()`-like methods',
recommended: false,
url: 'https://eslint.org/docs/latest/rules/no-implied-eval',
},
schema: [],
messages: {
impliedEval:
'Implied eval. Consider passing a function instead of a string.',
},
},
create(context) {
const GLOBAL_CANDIDATES = Object.freeze(['global', 'window', 'globalThis']);
const EVAL_LIKE_FUNC_PATTERN = /^(?:set(?:Interval|Timeout)|execScript)$/u;
const sourceCode = context.sourceCode;
/**
* Checks whether a node is evaluated as a string or not.
* @param {ASTNode} node A node to check.
* @returns {boolean} True if the node is evaluated as a string.
*/
function isEvaluatedString(node) {
if (
(node.type === 'Literal' && typeof node.value === 'string') ||
node.type === 'TemplateLiteral'
) {
return true;
}
if (node.type === 'BinaryExpression' && node.operator === '+') {
return isEvaluatedString(node.left) || isEvaluatedString(node.right);
}
return false;
}
/**
* Reports if the `CallExpression` node has evaluated argument.
* @param {ASTNode} node A CallExpression to check.
* @returns {void}
*/
function reportImpliedEvalCallExpression(node) {
const [firstArgument] = node.arguments;
if (firstArgument) {
const staticValue = getStaticValue(
firstArgument,
sourceCode.getScope(node)
);
const isStaticString =
staticValue && typeof staticValue.value === 'string';
const isString = isStaticString || isEvaluatedString(firstArgument);
if (isString) {
context.report({
node,
messageId: 'impliedEval',
});
}
}
}
/**
* Reports calls of `implied eval` via the global references.
* @param {Variable} globalVar A global variable to check.
* @returns {void}
*/
function reportImpliedEvalViaGlobal(globalVar) {
const { references, name } = globalVar;
references.forEach((ref) => {
const identifier = ref.identifier;
let node = identifier.parent;
while (astUtils.isSpecificMemberAccess(node, null, name)) {
node = node.parent;
}
if (
astUtils.isSpecificMemberAccess(node, null, EVAL_LIKE_FUNC_PATTERN)
) {
const calleeNode =
node.parent.type === 'ChainExpression' ? node.parent : node;
const parent = calleeNode.parent;
if (
parent.type === 'CallExpression' &&
parent.callee === calleeNode
) {
reportImpliedEvalCallExpression(parent);
}
}
});
}
//--------------------------------------------------------------------------
// Public
//--------------------------------------------------------------------------
return {
CallExpression(node) {
if (astUtils.isSpecificId(node.callee, EVAL_LIKE_FUNC_PATTERN)) {
reportImpliedEvalCallExpression(node);
}
},
'Program:exit'(node) {
const globalScope = sourceCode.getScope(node);
GLOBAL_CANDIDATES.map((candidate) =>
astUtils.getVariableByName(globalScope, candidate)
)
.filter((globalVar) => !!globalVar && globalVar.defs.length === 0)
.forEach(reportImpliedEvalViaGlobal);
},
};
},
};