| /** | |
|  * @fileoverview Rule that warns when identifier names that are | |
|  * specified in the configuration are used. | |
|  * @author Keith Cirkel (http://keithcirkel.co.uk) | |
|  */ | |
| 
 | |
| "use strict"; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Helpers | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** | |
|  * Checks whether the given node represents assignment target in a normal assignment or destructuring. | |
|  * @param {ASTNode} node The node to check. | |
|  * @returns {boolean} `true` if the node is assignment target. | |
|  */ | |
| function isAssignmentTarget(node) { | |
|     const parent = node.parent; | |
| 
 | |
|     return ( | |
| 
 | |
|         // normal assignment | |
|         ( | |
|             parent.type === "AssignmentExpression" && | |
|             parent.left === node | |
|         ) || | |
| 
 | |
|         // destructuring | |
|         parent.type === "ArrayPattern" || | |
|         parent.type === "RestElement" || | |
|         ( | |
|             parent.type === "Property" && | |
|             parent.value === node && | |
|             parent.parent.type === "ObjectPattern" | |
|         ) || | |
|         ( | |
|             parent.type === "AssignmentPattern" && | |
|             parent.left === node | |
|         ) | |
|     ); | |
| } | |
| 
 | |
| /** | |
|  * Checks whether the given node represents an imported name that is renamed in the same import/export specifier. | |
|  * | |
|  * Examples: | |
|  * import { a as b } from 'mod'; // node `a` is renamed import | |
|  * export { a as b } from 'mod'; // node `a` is renamed import | |
|  * @param {ASTNode} node `Identifier` node to check. | |
|  * @returns {boolean} `true` if the node is a renamed import. | |
|  */ | |
| function isRenamedImport(node) { | |
|     const parent = node.parent; | |
| 
 | |
|     return ( | |
|         ( | |
|             parent.type === "ImportSpecifier" && | |
|             parent.imported !== parent.local && | |
|             parent.imported === node | |
|         ) || | |
|         ( | |
|             parent.type === "ExportSpecifier" && | |
|             parent.parent.source && // re-export | |
|             parent.local !== parent.exported && | |
|             parent.local === node | |
|         ) | |
|     ); | |
| } | |
| 
 | |
| /** | |
|  * Checks whether the given node is an ObjectPattern destructuring. | |
|  * | |
|  * Examples: | |
|  * const { a : b } = foo; | |
|  * @param {ASTNode} node `Identifier` node to check. | |
|  * @returns {boolean} `true` if the node is in an ObjectPattern destructuring. | |
|  */ | |
| function isPropertyNameInDestructuring(node) { | |
|     const parent = node.parent; | |
| 
 | |
|     return ( | |
|         ( | |
|             !parent.computed && | |
|             parent.type === "Property" && | |
|             parent.parent.type === "ObjectPattern" && | |
|             parent.key === node | |
|         ) | |
|     ); | |
| } | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Rule Definition | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** @type {import('../shared/types').Rule} */ | |
| module.exports = { | |
|     meta: { | |
|         type: "suggestion", | |
| 
 | |
|         docs: { | |
|             description: "Disallow specified identifiers", | |
|             recommended: false, | |
|             url: "https://eslint.org/docs/latest/rules/id-denylist" | |
|         }, | |
| 
 | |
|         schema: { | |
|             type: "array", | |
|             items: { | |
|                 type: "string" | |
|             }, | |
|             uniqueItems: true | |
|         }, | |
|         messages: { | |
|             restricted: "Identifier '{{name}}' is restricted.", | |
|             restrictedPrivate: "Identifier '#{{name}}' is restricted." | |
|         } | |
|     }, | |
| 
 | |
|     create(context) { | |
| 
 | |
|         const denyList = new Set(context.options); | |
|         const reportedNodes = new Set(); | |
|         const sourceCode = context.sourceCode; | |
| 
 | |
|         let globalScope; | |
| 
 | |
|         /** | |
|          * Checks whether the given name is restricted. | |
|          * @param {string} name The name to check. | |
|          * @returns {boolean} `true` if the name is restricted. | |
|          * @private | |
|          */ | |
|         function isRestricted(name) { | |
|             return denyList.has(name); | |
|         } | |
| 
 | |
|         /** | |
|          * Checks whether the given node represents a reference to a global variable that is not declared in the source code. | |
|          * These identifiers will be allowed, as it is assumed that user has no control over the names of external global variables. | |
|          * @param {ASTNode} node `Identifier` node to check. | |
|          * @returns {boolean} `true` if the node is a reference to a global variable. | |
|          */ | |
|         function isReferenceToGlobalVariable(node) { | |
|             const variable = globalScope.set.get(node.name); | |
| 
 | |
|             return variable && variable.defs.length === 0 && | |
|                 variable.references.some(ref => ref.identifier === node); | |
|         } | |
| 
 | |
|         /** | |
|          * Determines whether the given node should be checked. | |
|          * @param {ASTNode} node `Identifier` node. | |
|          * @returns {boolean} `true` if the node should be checked. | |
|          */ | |
|         function shouldCheck(node) { | |
|             const parent = node.parent; | |
| 
 | |
|             /* | |
|              * Member access has special rules for checking property names. | |
|              * Read access to a property with a restricted name is allowed, because it can be on an object that user has no control over. | |
|              * Write access isn't allowed, because it potentially creates a new property with a restricted name. | |
|              */ | |
|             if ( | |
|                 parent.type === "MemberExpression" && | |
|                 parent.property === node && | |
|                 !parent.computed | |
|             ) { | |
|                 return isAssignmentTarget(parent); | |
|             } | |
| 
 | |
|             return ( | |
|                 parent.type !== "CallExpression" && | |
|                 parent.type !== "NewExpression" && | |
|                 !isRenamedImport(node) && | |
|                 !isPropertyNameInDestructuring(node) && | |
|                 !isReferenceToGlobalVariable(node) | |
|             ); | |
|         } | |
| 
 | |
|         /** | |
|          * Reports an AST node as a rule violation. | |
|          * @param {ASTNode} node The node to report. | |
|          * @returns {void} | |
|          * @private | |
|          */ | |
|         function report(node) { | |
| 
 | |
|             /* | |
|              * We used the range instead of the node because it's possible | |
|              * for the same identifier to be represented by two different | |
|              * nodes, with the most clear example being shorthand properties: | |
|              * { foo } | |
|              * In this case, "foo" is represented by one node for the name | |
|              * and one for the value. The only way to know they are the same | |
|              * is to look at the range. | |
|              */ | |
|             if (!reportedNodes.has(node.range.toString())) { | |
|                 const isPrivate = node.type === "PrivateIdentifier"; | |
| 
 | |
|                 context.report({ | |
|                     node, | |
|                     messageId: isPrivate ? "restrictedPrivate" : "restricted", | |
|                     data: { | |
|                         name: node.name | |
|                     } | |
|                 }); | |
|                 reportedNodes.add(node.range.toString()); | |
|             } | |
|         } | |
| 
 | |
|         return { | |
| 
 | |
|             Program(node) { | |
|                 globalScope = sourceCode.getScope(node); | |
|             }, | |
| 
 | |
|             [[ | |
|                 "Identifier", | |
|                 "PrivateIdentifier" | |
|             ]](node) { | |
|                 if (isRestricted(node.name) && shouldCheck(node)) { | |
|                     report(node); | |
|                 } | |
|             } | |
|         }; | |
|     } | |
| };
 |