biome correctness/noGlobalDirnameFilename: fix changes program behavior

Hypothesis Nemotron 3 Super predicted to fire fired 1×

If executed in CommonJS, import.meta.dirname/filename are undefined while __dirname/__filename exist.

Program

Output

(no stdout)
ReferenceError: __dirname is not defined in ES module scope

(no stdout)

Judge Nemotron 3 Ultra advisory program-bug · low

The program runs as an ES module where __dirname is not defined, causing a ReferenceError before the fix. The fix replaces it with import.meta.dirname, which is the correct ES module equivalent, so the behavioral change is due to the module system environment, not a bug in the rewrite itself.

Explanation Nemotron 3 Super unverified

The original script uses `__dirname`, which is unavailable in ES modules, causing a `ReferenceError` that exits with code 1. The replacement uses `import.meta.dirname`, which is only available when the file is treated as an ES module. If the environment still interprets the file as CommonJS (e.g., due to file extension or lack of `"type": "module"`), `import.meta` is undefined, making `import.meta.dirname` also throw a `ReferenceError`. However, if the environment now correctly treats it as an ES module, the error disappears and execution succeeds (exit 0). The behavioral change arises because the fix alters the module system’s interpretation of the file, affecting the availability of module-specific variables—not merely substituting equivalent values within the same system. This shift in execution context changes whether the program throws or runs, so the rewrite is not semantics-preserving.

Reproduce

file

prog.js (the before program)

minimized program

r2-p001.js

evidence sheet

r2-p001.md

regression fixture

r2-p001.js the minimized program with a header stating the observed change, for the tool's test suite

node prog.js
bunx @biomejs/biome lint --only=correctness/noGlobalDirnameFilename --write prog.js
node prog.js

Upstream search GitHub issues Tavily Nemotron 3 Super + Ultra

noGlobalDirnameFilename fix · __dirname usage in ES modules · import.meta.dirname replacement pattern · correctness noGlobalDirnameFilename linting

no duplicate or related report 35 hits triaged

Details

program

Non-ESM environment failure

hazard

If executed in CommonJS, import.meta.dirname/filename are undefined while __dirname/__filename exist.

oracle

exit 1 → 0 stderr before: ReferenceError: __dirname is not defined in ES module scope stderr after: (none)

run

2026-10-17T20-16-26-722Z-l85y-biome-correctness_noGlobalDirnameFilename

--- orig.js	2026-10-17 16:16:49.078932784 -0400
+++ fixed.js	2026-10-17 16:16:49.341929639 -0400
@@ -1,4 +1,4 @@
-const dir = __dirname;
+const dir = import.meta.dirname;
 console.log('original:', typeof dir === 'string' ? dir : 'not string');
 try {
   const fixed = import.meta.dirname;

Summary

- Name: noGlobalDirnameFilename
- Fix: safe
- Default severity: info
- Available from version: 2.0.0
- Diagnostic category: lint/correctness/noGlobalDirnameFilename


Description

 Disallow the use of `__dirname` and `__filename` in the global scope.

 They are [not available in ES modules](https://nodejs.org/api/esm.html#esm_no_filename_or_dirname).
 Starting with Node.js 20.11, `import.meta.dirname` and `import.meta.filename` have been introduced in ES modules, providing identical functionality to `__dirname` and `__filename` in CommonJS (CJS).

Examples

Invalid

 ```js,expect_diagnostic
 const dirname = __dirname;
 ```

 ```js,expect_diagnostic
 const filename = __filename;
 ```

 ``` js,expect_diagnostic
 const foo = { __filename }
 ```

 ```js,expect_diagnostic
 if (__dirname.startsWith("/project/src/")) {}
 ```

Valid

 ```js
 const dirname = import.meta.dirname
 const filename = import.meta.filename
 const foo = {__filename: import.meta.filename };
 if (import.meta.dirname.startsWith("/project/src/")) {}
 ```