biome correctness/noGlobalDirnameFilename: fix changes program behavior

Hypothesis Nemotron 3 Super predicted to fire fired 1×

The fix does not preserve trailing comments on the line if the replacement alters whitespace in a way that moves or drops line comments

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 undefined, causing a ReferenceError before the fix. The rewrite to import.meta.dirname is the documented ES-module replacement, so the behavior change stems from the module system environment, not a flaw in the fix itself.

Explanation Nemotron 3 Super unverified

The original code uses `__dirname`, which is undefined in ES modules, causing a ReferenceError. The replacement `import.meta.dirname` provides the directory name of the current module file in ES module scope, resolving the error. Since the behavior changes from throwing an exception to executing successfully, the rewrite alters program semantics despite preserving the comment. This change is not semantics-preserving because it modifies the program’s execution outcome.

Reproduce

file

prog.js (the before program)

minimized program

r1-p006.js

evidence sheet

r1-p006.md

regression fixture

r1-p006.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 · noGlobalDirnameFilename linting pattern · import.meta.dirname replacement behavior

• duplicate biomejs/biome/issues/11028 same rule (noGlobalDirnameFilename) and same construct (__dirname rewrite in module context)

Details

program

__dirname; // comment - tests trailing comment preservation

hazard

The fix does not preserve trailing comments on the line if the replacement alters whitespace in a way that moves or drops line comments

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 16:16:41.117029086 -0400
+++ fixed.js	2026-10-17 16:16:41.383025839 -0400
@@ -1,3 +1,3 @@
 // Hazard 6
-__dirname; // this comment must stay
+import.meta.dirname; // this comment must stay
 console.log('ok');

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/")) {}
 ```