[#535] StreamingResponse: mutating the finalized "final" stream activity (delete or update) after end_stream() re-hangs the Teams client's typing/streaming indicator

[Cecilia Avila (ceciliaavila)]

Fixes #535

Description

This pull request enhances the typing indicator's behavior by ensuring it stops when update or delete activity events occur, not just when send activities are triggered. It introduces new hooks for update and delete activities, updates the stub context in tests to support these hooks, and adds new tests to verify this behavior.

Typing indicator enhancements:

• Added handlers in TypingIndicator to stop the typing indicator loop on update and delete activity events, in addition to existing send activities. (microsoft_agents/hosting/core/app/typing_indicator.py)

Testing improvements:

• Updated StubTurnContext in tests to support on_update_activity and on_delete_activity handlers, allowing tests to simulate these events. (test_typing_indicator.py)
• Added new parameterized tests to verify that update and delete operations correctly stop the typing indicator before proceeding with the mutation. (test_typing_indicator.py)

Testing

Here we can see the issue being reproduced (typing indicator is showing even after the activity was updated)

And here we can see the fix applied.

[Copilot]

🟡 Changes recommended

The new delete-mutation test uses a raw activity-id string instead of the ConversationReference that TurnContext.delete_activity() actually emits to handlers, reducing the test’s fidelity and risking masked regressions.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

This pull request updates the TypingIndicator in microsoft-agents-hosting-core to stop its background typing loop not only when outgoing activities are sent, but also when activities are updated or deleted—addressing a Teams-specific scenario where mutating a finalized streamed activity can leave the client’s typing/streaming indicator stuck.

Changes:

• Stop the typing indicator loop when TurnContext.update_activity(...) is invoked.
• Stop the typing indicator loop when TurnContext.delete_activity(...) is invoked.
• Extend typing-indicator tests with a new parameterized test covering update/delete mutation hooks.

File summaries

File	Description
libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/app/typing_indicator.py	Registers update/delete hooks to stop the typing loop when those mutations occur.
tests/hosting_core/app/test_typing_indicator.py	Adds stub hook support and a new test ensuring mutation hooks stop typing before proceeding.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Lite

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[Copilot]

🟢 Approval recommended

The changes are small, consistent with existing TurnContext hook patterns, and include targeted tests covering the new stop conditions for update/delete mutations.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0 new
• Review effort level: Lite

[Copilot]

🟢 Approval recommended

The change is small, aligns with existing TurnContext hook APIs, and is covered by focused unit tests validating the new behavior.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0 new
• Review effort level: Lite