| /** | |
|  * @fileoverview Rule to enforce declarations in program or function body root. | |
|  * @author Brandon Mills | |
|  */ | |
| 
 | |
| "use strict"; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Requirements | |
| //------------------------------------------------------------------------------ | |
|  | |
| const astUtils = require("./utils/ast-utils"); | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Rule Definition | |
| //------------------------------------------------------------------------------ | |
|  | |
| const validParent = new Set(["Program", "StaticBlock", "ExportNamedDeclaration", "ExportDefaultDeclaration"]); | |
| const validBlockStatementParent = new Set(["FunctionDeclaration", "FunctionExpression", "ArrowFunctionExpression"]); | |
| 
 | |
| /** | |
|  * Finds the nearest enclosing context where this rule allows declarations and returns its description. | |
|  * @param {ASTNode} node Node to search from. | |
|  * @returns {string} Description. One of "program", "function body", "class static block body". | |
|  */ | |
| function getAllowedBodyDescription(node) { | |
|     let { parent } = node; | |
| 
 | |
|     while (parent) { | |
| 
 | |
|         if (parent.type === "StaticBlock") { | |
|             return "class static block body"; | |
|         } | |
| 
 | |
|         if (astUtils.isFunction(parent)) { | |
|             return "function body"; | |
|         } | |
| 
 | |
|         ({ parent } = parent); | |
|     } | |
| 
 | |
|     return "program"; | |
| } | |
| 
 | |
| /** @type {import('../shared/types').Rule} */ | |
| module.exports = { | |
|     meta: { | |
|         type: "problem", | |
| 
 | |
|         docs: { | |
|             description: "Disallow variable or `function` declarations in nested blocks", | |
|             recommended: true, | |
|             url: "https://eslint.org/docs/latest/rules/no-inner-declarations" | |
|         }, | |
| 
 | |
|         schema: [ | |
|             { | |
|                 enum: ["functions", "both"] | |
|             } | |
|         ], | |
| 
 | |
|         messages: { | |
|             moveDeclToRoot: "Move {{type}} declaration to {{body}} root." | |
|         } | |
|     }, | |
| 
 | |
|     create(context) { | |
| 
 | |
|         /** | |
|          * Ensure that a given node is at a program or function body's root. | |
|          * @param {ASTNode} node Declaration node to check. | |
|          * @returns {void} | |
|          */ | |
|         function check(node) { | |
|             const parent = node.parent; | |
| 
 | |
|             if ( | |
|                 parent.type === "BlockStatement" && validBlockStatementParent.has(parent.parent.type) | |
|             ) { | |
|                 return; | |
|             } | |
| 
 | |
|             if (validParent.has(parent.type)) { | |
|                 return; | |
|             } | |
| 
 | |
|             context.report({ | |
|                 node, | |
|                 messageId: "moveDeclToRoot", | |
|                 data: { | |
|                     type: (node.type === "FunctionDeclaration" ? "function" : "variable"), | |
|                     body: getAllowedBodyDescription(node) | |
|                 } | |
|             }); | |
|         } | |
| 
 | |
| 
 | |
|         return { | |
| 
 | |
|             FunctionDeclaration: check, | |
|             VariableDeclaration(node) { | |
|                 if (context.options[0] === "both" && node.kind === "var") { | |
|                     check(node); | |
|                 } | |
|             } | |
| 
 | |
|         }; | |
| 
 | |
|     } | |
| };
 |