| /** | |
|  * @fileoverview Rule to flag when a function has too many parameters | |
|  * @author Ilya Volodin | |
|  */ | |
| 
 | |
| "use strict"; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Requirements | |
| //------------------------------------------------------------------------------ | |
|  | |
| const astUtils = require("./utils/ast-utils"); | |
| const { upperCaseFirst } = require("../shared/string-utils"); | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Rule Definition | |
| //------------------------------------------------------------------------------ | |
|  | |
| /** @type {import('../shared/types').Rule} */ | |
| module.exports = { | |
|     meta: { | |
|         type: "suggestion", | |
| 
 | |
|         docs: { | |
|             description: "Enforce a maximum number of parameters in function definitions", | |
|             recommended: false, | |
|             url: "https://eslint.org/docs/latest/rules/max-params" | |
|         }, | |
| 
 | |
|         schema: [ | |
|             { | |
|                 oneOf: [ | |
|                     { | |
|                         type: "integer", | |
|                         minimum: 0 | |
|                     }, | |
|                     { | |
|                         type: "object", | |
|                         properties: { | |
|                             maximum: { | |
|                                 type: "integer", | |
|                                 minimum: 0 | |
|                             }, | |
|                             max: { | |
|                                 type: "integer", | |
|                                 minimum: 0 | |
|                             } | |
|                         }, | |
|                         additionalProperties: false | |
|                     } | |
|                 ] | |
|             } | |
|         ], | |
|         messages: { | |
|             exceed: "{{name}} has too many parameters ({{count}}). Maximum allowed is {{max}}." | |
|         } | |
|     }, | |
| 
 | |
|     create(context) { | |
|         const sourceCode = context.sourceCode; | |
|         const option = context.options[0]; | |
|         let numParams = 3; | |
| 
 | |
|         if ( | |
|             typeof option === "object" && | |
|             (Object.prototype.hasOwnProperty.call(option, "maximum") || Object.prototype.hasOwnProperty.call(option, "max")) | |
|         ) { | |
|             numParams = option.maximum || option.max; | |
|         } | |
|         if (typeof option === "number") { | |
|             numParams = option; | |
|         } | |
| 
 | |
|         /** | |
|          * Checks a function to see if it has too many parameters. | |
|          * @param {ASTNode} node The node to check. | |
|          * @returns {void} | |
|          * @private | |
|          */ | |
|         function checkFunction(node) { | |
|             if (node.params.length > numParams) { | |
|                 context.report({ | |
|                     loc: astUtils.getFunctionHeadLoc(node, sourceCode), | |
|                     node, | |
|                     messageId: "exceed", | |
|                     data: { | |
|                         name: upperCaseFirst(astUtils.getFunctionNameWithKind(node)), | |
|                         count: node.params.length, | |
|                         max: numParams | |
|                     } | |
|                 }); | |
|             } | |
|         } | |
| 
 | |
|         return { | |
|             FunctionDeclaration: checkFunction, | |
|             ArrowFunctionExpression: checkFunction, | |
|             FunctionExpression: checkFunction | |
|         }; | |
| 
 | |
|     } | |
| };
 |