Fix Race Condition in TestListenerCustomConnIDs#782
Merged
adrianosela merged 1 commit intopion:masterfrom Jan 21, 2026
Merged
Conversation
This test had a race condition caused by UDP port re-use. When clients rapidly open and close connections, the OS would sometimes assign the same port number to different clients. Since the test used the *net.UDPConn's LocalAddr as the unique identifier for clients, this would result in the same unique identifier being assigned to multiple clients (and thus not being unique!). To fix this, we use an identifier based off the client index in the test's loop e.g. "client-%d"
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## master #782 +/- ##
==========================================
- Coverage 81.65% 81.61% -0.04%
==========================================
Files 105 105
Lines 5837 5837
==========================================
- Hits 4766 4764 -2
- Misses 687 689 +2
Partials 384 384
Flags with carried forward coverage won't be shown. Click here to find out more. ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
|
JoTurk
approved these changes
Jan 21, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Fix Race Condition in TestListenerCustomConnIDs
Sometimes this test would fail in CI (intermittently):
This test had a race condition caused by UDP port re-use. When clients rapidly open and close connections, the OS would sometimes assign the same port number to different clients. Since the test used the *net.UDPConn's LocalAddr as the unique identifier for clients, this would result in the same unique identifier being assigned to multiple clients (and thus not being unique!).
To fix this, we use an identifier based off the client index in the test's loop e.g. "client-%d"
How to Reproduce
Run the test 50 times
Always 1 or 2 (out of 50) failures on my MacBook.
How to Verify Fix
Ran it 1000 times and got no failures.