flake: TestAdvisorHappyPath_RootChat

[flake-investigator]

CI Run Link: https://github.com/coder/coder/actions/runs/26492817796
Failing Job: https://github.com/coder/coder/actions/runs/26492817796/job/78014053269 (test-go-pg (macos-latest))
Failure time: 2026-05-27T05:49:50Z (same window as Slack alert)

Commit Info:

• SHA: 916094c71cdbc93ef7bedf2c9b3c3dac22cc411e
• Author: TJ (tracy@coder.com)
• Commit: coder/coder@916094c

Failure evidence:

=== FAIL: coderd/x/chatd TestAdvisorHappyPath_RootChat (1.45s)
    chatd_test.go:10035:
        Error:       Not equal:
            expected: []string{"break the problem ", "into smaller pieces first"}
            actual  : []string(nil)
        Test:        TestAdvisorHappyPath_RootChat
        Messages:    advisor nested text deltas must stream into the parent tool card
DONE 24437 tests, 90 skipped, 1 failure in 902.622s

Root cause assessment:

• Likely flaky test / timing in advisor streaming: the live collector did not capture the expected nested text deltas, resulting in nil vs expected advisorDeltas. This suggests a race between advisor stream emission and the live collector consumption.

Data race / panic / OOM checks:

• Searched logs for WARNING: DATA RACE, panic:, out of memory, signal: killed — none found.

Precise assignment analysis:

• Test function location: coderd/x/chatd/chatd_test.go around TestAdvisorHappyPath_RootChat (lines ~9856–10035).
• git log --oneline -10 --follow coderd/x/chatd/chatd_test.go shows the most recent substantive change touching this file is:
  • 8b1705e “feat: route chatd provider traffic through aibridge (#25629)” (Michael Suchacz / @ibetitsmike)
• Unable to isolate a narrower line-level blame in this environment; assigning to the most recent meaningful modifier of the chatd test file.

Assignment:

• @ibetitsmike

Related issues:

• No existing coder/internal issues found for TestAdvisorHappyPath_RootChat or the error message.

Reproduction (best effort):

• go test ./coderd/x/chatd -run TestAdvisorHappyPath_RootChat -count=1