[kinyoklion]

Summary

The file-based override source drops a path that is listed more than once, so that the file's entries do not collide with themselves. The comparison was exact. On Windows, where file names ignore case, a path repeated in a different case (C:\overrides\a.json and c:\Overrides\A.JSON) survived, and every key in that file then failed as its own duplicate under the default fail handling, so the reload failed and no overrides from it applied.

On Windows the comparison now ignores case. Elsewhere it stays exact, because a case-sensitive file system can hold both names as different files. The platform is read from the platform data the SDK already reports (os.name of Windows), so the shared package does not depend on Node's process.

This is the gap that Bugbot found in the .NET port (launchdarkly/dotnet-core#367).

Tests

Two tests in createOverrideSource.test.ts set the platform's OS name. On Windows, a path repeated in a different case is dropped with the existing warning; this test fails without the change and fails again with it reverted. On Linux, paths that differ only in case are both kept. The sdk-server suite passes (1561 passed, 7 skipped), and lint and formatting are clean.

_{Opened from termag}

SDK-3419

---

Note

Overview
File override path deduplication now treats paths that differ only by case as the same file when platformData().os.name is Windows, dropping repeats with the existing warning. On other platforms, deduplication stays case-sensitive so two paths can still refer to distinct files.

Implementation replaces indexOf-based filtering with a Set keyed by the path or its lowercase form on Windows. Tests add makeContextOn to mock OS name and cover Windows (drop + warn) vs Linux (keep both, no warn).

^{Reviewed by Cursor Bugbot for commit db5a4ab. Bugbot is set up for automated code reviews on this repo. Configure here.}

[kinyoklion]

bugbot review

[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 25998 bytes
Compressed size limit: 44000
Uncompressed size: 167978 bytes

[github-actions]

@launchdarkly/js-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 32220 bytes
Compressed size limit: 32500
Uncompressed size: 152548 bytes

[github-actions]

@launchdarkly/js-client-sdk size report
This is the brotli compressed size of the ESM build.
Compressed size: 34386 bytes
Compressed size limit: 35000
Uncompressed size: 122562 bytes

[kinyoklion]

bugbot review

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

Comment @cursor review or bugbot run to trigger another review on this PR

^{Reviewed by Cursor Bugbot for commit db5a4ab. Configure here.}