codtracker-js/node_modules/eslint/lib/rules/no-case-declarations.js
2025-04-17 07:44:37 -04:00

81 lines
1.8 KiB
JavaScript

/**
* @fileoverview Rule to flag use of an lexical declarations inside a case clause
* @author Erik Arvidsson
*/
"use strict";
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
type: "suggestion",
docs: {
description: "Disallow lexical declarations in case clauses",
recommended: true,
url: "https://eslint.org/docs/latest/rules/no-case-declarations",
},
hasSuggestions: true,
schema: [],
messages: {
addBrackets: "Add {} brackets around the case block.",
unexpected: "Unexpected lexical declaration in case block.",
},
},
create(context) {
/**
* Checks whether or not a node is a lexical declaration.
* @param {ASTNode} node A direct child statement of a switch case.
* @returns {boolean} Whether or not the node is a lexical declaration.
*/
function isLexicalDeclaration(node) {
switch (node.type) {
case "FunctionDeclaration":
case "ClassDeclaration":
return true;
case "VariableDeclaration":
return node.kind !== "var";
default:
return false;
}
}
return {
SwitchCase(node) {
for (let i = 0; i < node.consequent.length; i++) {
const statement = node.consequent[i];
if (isLexicalDeclaration(statement)) {
context.report({
node: statement,
messageId: "unexpected",
suggest: [
{
messageId: "addBrackets",
fix: fixer => [
fixer.insertTextBefore(
node.consequent[0],
"{ ",
),
fixer.insertTextAfter(
node.consequent.at(-1),
" }",
),
],
},
],
});
}
}
},
};
},
};