74 lines
1.9 KiB
JavaScript
74 lines
1.9 KiB
JavaScript
/**
|
|
* @fileoverview Disallow sparse arrays
|
|
* @author Nicholas C. Zakas
|
|
*/
|
|
"use strict";
|
|
|
|
const astUtils = require("./utils/ast-utils");
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
/** @type {import('../shared/types').Rule} */
|
|
module.exports = {
|
|
meta: {
|
|
type: "problem",
|
|
|
|
docs: {
|
|
description: "Disallow sparse arrays",
|
|
recommended: true,
|
|
url: "https://eslint.org/docs/latest/rules/no-sparse-arrays"
|
|
},
|
|
|
|
schema: [],
|
|
|
|
messages: {
|
|
unexpectedSparseArray: "Unexpected comma in middle of array."
|
|
}
|
|
},
|
|
|
|
create(context) {
|
|
|
|
|
|
//--------------------------------------------------------------------------
|
|
// Public
|
|
//--------------------------------------------------------------------------
|
|
|
|
return {
|
|
|
|
ArrayExpression(node) {
|
|
if (!node.elements.includes(null)) {
|
|
return;
|
|
}
|
|
|
|
const { sourceCode } = context;
|
|
let commaToken;
|
|
|
|
for (const [index, element] of node.elements.entries()) {
|
|
if (index === node.elements.length - 1 && element) {
|
|
return;
|
|
}
|
|
|
|
commaToken = sourceCode.getTokenAfter(
|
|
element ?? commaToken ?? sourceCode.getFirstToken(node),
|
|
astUtils.isCommaToken
|
|
);
|
|
|
|
if (element) {
|
|
continue;
|
|
}
|
|
|
|
context.report({
|
|
node,
|
|
loc: commaToken.loc,
|
|
messageId: "unexpectedSparseArray"
|
|
});
|
|
}
|
|
}
|
|
|
|
};
|
|
|
|
}
|
|
};
|