default-param-last.js•1.59 kB
/**
* @fileoverview enforce default parameters to be last
* @author Chiawen Chen
*/
"use strict";
/** @type {import('../shared/types').Rule} */
module.exports = {
meta: {
type: "suggestion",
docs: {
description: "Enforce default parameters to be last",
recommended: false,
url: "https://eslint.org/docs/latest/rules/default-param-last"
},
schema: [],
messages: {
shouldBeLast: "Default parameters should be last."
}
},
create(context) {
/**
* Handler for function contexts.
* @param {ASTNode} node function node
* @returns {void}
*/
function handleFunction(node) {
let hasSeenPlainParam = false;
for (let i = node.params.length - 1; i >= 0; i -= 1) {
const param = node.params[i];
if (
param.type !== "AssignmentPattern" &&
param.type !== "RestElement"
) {
hasSeenPlainParam = true;
continue;
}
if (hasSeenPlainParam && param.type === "AssignmentPattern") {
context.report({
node: param,
messageId: "shouldBeLast"
});
}
}
}
return {
FunctionDeclaration: handleFunction,
FunctionExpression: handleFunction,
ArrowFunctionExpression: handleFunction
};
}
};