| /** | |
|  * @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('../shared/types').Rule} */ | |
| 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); | |
|             } | |
|         }; | |
| 
 | |
|     } | |
| };
 |