2 * @fileoverview Rule to
3 * @author Toru Nagashima
8 //------------------------------------------------------------------------------
10 //------------------------------------------------------------------------------
13 * Gets the variable object of `arguments` which is defined implicitly.
14 * @param {eslint-scope.Scope} scope A scope to get.
15 * @returns {eslint-scope.Variable} The found variable object.
17 function getVariableOfArguments(scope) {
18 const variables = scope.variables;
20 for (let i = 0; i < variables.length; ++i) {
21 const variable = variables[i];
23 if (variable.name === "arguments") {
26 * If there was a parameter which is named "arguments", the implicit "arguments" is not defined.
27 * So does fast return with null.
29 return (variable.identifiers.length === 0) ? variable : null;
33 /* istanbul ignore next : unreachable */
38 * Checks if the given reference is not normal member access.
40 * - arguments .... true // not member access
41 * - arguments[i] .... true // computed member access
42 * - arguments[0] .... true // computed member access
43 * - arguments.length .... false // normal member access
44 * @param {eslint-scope.Reference} reference The reference to check.
45 * @returns {boolean} `true` if the reference is not normal member access.
47 function isNotNormalMemberAccess(reference) {
48 const id = reference.identifier;
49 const parent = id.parent;
52 parent.type === "MemberExpression" &&
53 parent.object === id &&
58 //------------------------------------------------------------------------------
60 //------------------------------------------------------------------------------
67 description: "require rest parameters instead of `arguments`",
68 category: "ECMAScript 6",
70 url: "https://eslint.org/docs/rules/prefer-rest-params"
79 * Reports a given reference.
80 * @param {eslint-scope.Reference} reference A reference to report.
83 function report(reference) {
85 node: reference.identifier,
86 loc: reference.identifier.loc,
87 message: "Use the rest parameters instead of 'arguments'."
92 * Reports references of the implicit `arguments` variable if exist.
95 function checkForArguments() {
96 const argumentsVar = getVariableOfArguments(context.getScope());
101 .filter(isNotNormalMemberAccess)
107 "FunctionDeclaration:exit": checkForArguments,
108 "FunctionExpression:exit": checkForArguments