ifc-language-server/node_modules/eslint/lib/rules/no-empty-character-class.js
Ryan Schultz 8afacf268a Implemented a working Language Server Protocol (LSP) for IFC files with:
- Hover provider showing entity information and type
- Go-to-definition (F12) for entity references
- Basic IFC file validation (ISO-10303-21 header check)
- Entity parsing with regex-based detection
- Proper CommonJS module system (avoiding ES module issues)

This replaces the broken baseline from ifc-developer-tools which had:
- Non-functional ES module configuration
- Circular dependency issues
- Parser crashes
- Non-working PositionVisitor

Built on Microsoft's LSP example template for a clean, maintainable foundation.

Next: Add hierarchical entity dependency tree in hover tooltip."
2025-12-07 10:20:07 -06:00

83 lines
1.9 KiB
JavaScript

/**
* @fileoverview Rule to flag the use of empty character classes in regular expressions
* @author Ian Christian Myers
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const { RegExpParser, visitRegExpAST } = require("@eslint-community/regexpp");
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
const parser = new RegExpParser();
const QUICK_TEST_REGEX = /\[\]/u;
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
type: "problem",
docs: {
description:
"Disallow empty character classes in regular expressions",
recommended: true,
url: "https://eslint.org/docs/latest/rules/no-empty-character-class",
},
schema: [],
messages: {
unexpected: "Empty class.",
},
},
create(context) {
return {
"Literal[regex]"(node) {
const { pattern, flags } = node.regex;
if (!QUICK_TEST_REGEX.test(pattern)) {
return;
}
let regExpAST;
try {
regExpAST = parser.parsePattern(
pattern,
0,
pattern.length,
{
unicode: flags.includes("u"),
unicodeSets: flags.includes("v"),
},
);
} catch {
// Ignore regular expressions that regexpp cannot parse
return;
}
visitRegExpAST(regExpAST, {
onCharacterClassEnter(characterClass) {
if (
!characterClass.negate &&
characterClass.elements.length === 0
) {
context.report({ node, messageId: "unexpected" });
}
},
});
},
};
},
};