150 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			150 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| /**
 | |
|  * @fileoverview Disallow Labeled Statements
 | |
|  * @author Nicholas C. Zakas
 | |
|  */
 | |
| "use strict";
 | |
| 
 | |
| //------------------------------------------------------------------------------
 | |
| // Requirements
 | |
| //------------------------------------------------------------------------------
 | |
| 
 | |
| const astUtils = require("./utils/ast-utils");
 | |
| 
 | |
| //------------------------------------------------------------------------------
 | |
| // Rule Definition
 | |
| //------------------------------------------------------------------------------
 | |
| 
 | |
| /** @type {import('../shared/types').Rule} */
 | |
| module.exports = {
 | |
|     meta: {
 | |
|         type: "suggestion",
 | |
| 
 | |
|         docs: {
 | |
|             description: "Disallow labeled statements",
 | |
|             recommended: false,
 | |
|             url: "https://eslint.org/docs/latest/rules/no-labels"
 | |
|         },
 | |
| 
 | |
|         schema: [
 | |
|             {
 | |
|                 type: "object",
 | |
|                 properties: {
 | |
|                     allowLoop: {
 | |
|                         type: "boolean",
 | |
|                         default: false
 | |
|                     },
 | |
|                     allowSwitch: {
 | |
|                         type: "boolean",
 | |
|                         default: false
 | |
|                     }
 | |
|                 },
 | |
|                 additionalProperties: false
 | |
|             }
 | |
|         ],
 | |
| 
 | |
|         messages: {
 | |
|             unexpectedLabel: "Unexpected labeled statement.",
 | |
|             unexpectedLabelInBreak: "Unexpected label in break statement.",
 | |
|             unexpectedLabelInContinue: "Unexpected label in continue statement."
 | |
|         }
 | |
|     },
 | |
| 
 | |
|     create(context) {
 | |
|         const options = context.options[0];
 | |
|         const allowLoop = options && options.allowLoop;
 | |
|         const allowSwitch = options && options.allowSwitch;
 | |
|         let scopeInfo = null;
 | |
| 
 | |
|         /**
 | |
|          * Gets the kind of a given node.
 | |
|          * @param {ASTNode} node A node to get.
 | |
|          * @returns {string} The kind of the node.
 | |
|          */
 | |
|         function getBodyKind(node) {
 | |
|             if (astUtils.isLoop(node)) {
 | |
|                 return "loop";
 | |
|             }
 | |
|             if (node.type === "SwitchStatement") {
 | |
|                 return "switch";
 | |
|             }
 | |
|             return "other";
 | |
|         }
 | |
| 
 | |
|         /**
 | |
|          * Checks whether the label of a given kind is allowed or not.
 | |
|          * @param {string} kind A kind to check.
 | |
|          * @returns {boolean} `true` if the kind is allowed.
 | |
|          */
 | |
|         function isAllowed(kind) {
 | |
|             switch (kind) {
 | |
|                 case "loop": return allowLoop;
 | |
|                 case "switch": return allowSwitch;
 | |
|                 default: return false;
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         /**
 | |
|          * Checks whether a given name is a label of a loop or not.
 | |
|          * @param {string} label A name of a label to check.
 | |
|          * @returns {boolean} `true` if the name is a label of a loop.
 | |
|          */
 | |
|         function getKind(label) {
 | |
|             let info = scopeInfo;
 | |
| 
 | |
|             while (info) {
 | |
|                 if (info.label === label) {
 | |
|                     return info.kind;
 | |
|                 }
 | |
|                 info = info.upper;
 | |
|             }
 | |
| 
 | |
|             /* c8 ignore next */
 | |
|             return "other";
 | |
|         }
 | |
| 
 | |
|         //--------------------------------------------------------------------------
 | |
|         // Public
 | |
|         //--------------------------------------------------------------------------
 | |
| 
 | |
|         return {
 | |
|             LabeledStatement(node) {
 | |
|                 scopeInfo = {
 | |
|                     label: node.label.name,
 | |
|                     kind: getBodyKind(node.body),
 | |
|                     upper: scopeInfo
 | |
|                 };
 | |
|             },
 | |
| 
 | |
|             "LabeledStatement:exit"(node) {
 | |
|                 if (!isAllowed(scopeInfo.kind)) {
 | |
|                     context.report({
 | |
|                         node,
 | |
|                         messageId: "unexpectedLabel"
 | |
|                     });
 | |
|                 }
 | |
| 
 | |
|                 scopeInfo = scopeInfo.upper;
 | |
|             },
 | |
| 
 | |
|             BreakStatement(node) {
 | |
|                 if (node.label && !isAllowed(getKind(node.label.name))) {
 | |
|                     context.report({
 | |
|                         node,
 | |
|                         messageId: "unexpectedLabelInBreak"
 | |
|                     });
 | |
|                 }
 | |
|             },
 | |
| 
 | |
|             ContinueStatement(node) {
 | |
|                 if (node.label && !isAllowed(getKind(node.label.name))) {
 | |
|                     context.report({
 | |
|                         node,
 | |
|                         messageId: "unexpectedLabelInContinue"
 | |
|                     });
 | |
|                 }
 | |
|             }
 | |
|         };
 | |
| 
 | |
|     }
 | |
| };
 |