[Bryan Chen (bryanchen-d)]

Main CI 497216 failed on Windows x64 Electron unit with one test:

CopilotAgent › createChat activeClient eager-claim › setClientCustomizations publishes parsed agents in SessionCustomizationUpdated
AssertionError: expected SessionCustomizationUpdated to carry parsed children

Cause

After setting the active client's customizations, the test slept a fixed setTimeout(50) "for the deferred resolution chain in PluginController.sync" and then asserted. That chain parses agents/helper.md from a real temp folder through TestDiskFileSystemProvider, so on a slow or loaded agent the parsed update arrives after 50 ms and the assertion runs too early. The commit in range (#348151) doesn't touch the agent host.

Change

Test-only. Wait for the SessionCustomizationUpdated action that carries parsed children, using the same Event.toPromise(Event.filter(agent.onDidChatProgress, …)) pattern as other tests in this file. The promise is created before the customizations are set, so the action can't be missed. Exactly one such update is published (checked with a temporary 1 s probe), so the assertions still see the same final state.

Validation

• Ran the test 20 times while 64 busy-loop processes saturated all 32 cores: 0/20 pass on main (all on carry parsed children), 20/20 pass with this change.
• Unloaded: passes in about 100 ms, as before.
• The full copilotAgent.test.ts run gives the same pass/fail counts with and without the change. The local failures come from a missing vscode-sqlite3 native build in my borrowed install.
• tsc --project src/tsconfig.json --noEmit reports no errors in this file.

Authored with Copilot

[Copilot]

🟢 Approval recommended

No active review issues were identified for the test-only change replacing a fixed delay with an event-based wait.

No open issues 🎉

What changed in this PR

This test-only change removes a timing-dependent wait from the Agent Host customization test, addressing failures on slow or heavily loaded CI machines without changing production behavior.

Changes:

• Replace the fixed 50 ms delay with an event-based wait for SessionCustomizationUpdated containing parsed children.
• Register the listener before setting customizations to avoid missing the update, while preserving existing assertions.

File	Description
src/​vs/​platform/​agentHost/​test/​node/​copilotAgent.test.ts	Wait for parsed plugin children to be published instead of relying on a fixed delay.

_{Review effort: Balanced}