72 lines
2.0 KiB
Plaintext
72 lines
2.0 KiB
Plaintext
/**
|
|
* @fileoverview Rule to disallow a duplicate case label.
|
|
* @author Dieter Oberkofler
|
|
* @author Burak Yigit Kaya
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Requirements
|
|
//------------------------------------------------------------------------------
|
|
|
|
const astUtils = require("./utils/ast-utils");
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
/** @type {import('../shared/types').Rule} */
|
|
module.exports = {
|
|
meta: {
|
|
type: "problem",
|
|
|
|
docs: {
|
|
description: "Disallow duplicate case labels",
|
|
recommended: true,
|
|
url: "https://eslint.org/docs/latest/rules/no-duplicate-case"
|
|
},
|
|
|
|
schema: [],
|
|
|
|
messages: {
|
|
unexpected: "Duplicate case label."
|
|
}
|
|
},
|
|
|
|
create(context) {
|
|
const sourceCode = context.sourceCode;
|
|
|
|
/**
|
|
* Determines whether the two given nodes are considered to be equal.
|
|
* @param {ASTNode} a First node.
|
|
* @param {ASTNode} b Second node.
|
|
* @returns {boolean} `true` if the nodes are considered to be equal.
|
|
*/
|
|
function equal(a, b) {
|
|
if (a.type !== b.type) {
|
|
return false;
|
|
}
|
|
|
|
return astUtils.equalTokens(a, b, sourceCode);
|
|
}
|
|
return {
|
|
SwitchStatement(node) {
|
|
const previousTests = [];
|
|
|
|
for (const switchCase of node.cases) {
|
|
if (switchCase.test) {
|
|
const test = switchCase.test;
|
|
|
|
if (previousTests.some(previousTest => equal(previousTest, test))) {
|
|
context.report({ node: switchCase, messageId: "unexpected" });
|
|
} else {
|
|
previousTests.push(test);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
};
|
|
}
|
|
};
|