Route open_thread through load_agent_thread to prevent duplicate sessions#53859
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Route open_thread through load_agent_thread to prevent duplicate sessions#53859
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When two ConversationViews share the same session (because open_thread found the session still in the HashMap and reused it), closing the session from the first view removes the entry entirely, breaking the second view's ability to prompt. This test reproduces the race deterministically: 1. CV1 creates a session 2. CV2 calls open_thread, reuses the existing session 3. CV1 calls close_session, removing the entry 4. CV2 tries to prompt — gets "Session not found"
When multiple ConversationViews share the same NativeAgent session (because open_thread found it still in the HashMap), a close_session call from one view would remove the entry, breaking all other views with "Session not found". Add a ref_count to Session: register_session starts at 1, open_thread increments when reusing an existing session, and close_session only removes the entry when the count reaches zero.
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Add a comment to test_close_session_does_not_remove_reused_session explaining how clicking a @thread mention link (or pasting a thread link, or opening one via the CLI) to the currently-active thread can produce two ConversationViews sharing the same NativeAgent session, leading to the race that the ref-counting fix prevents.
…ions AgentPanel::open_thread (called when clicking @thread mention links, pasting thread links, or opening threads via the CLI) was calling external_thread directly, bypassing the de-duplication guards in load_agent_thread. This meant clicking a thread link to the currently-active thread would create a redundant ConversationView sharing the same NativeAgent session. When the old CV was later evicted from background_threads, its on_release called close_all_sessions, removing the session and breaking the surviving CV with "Session not found". Fix this by routing open_thread through load_agent_thread, which checks the active view, retained threads, and background threads before creating a new ConversationView. This prevents the duplicate from being created in the first place. Also removes the Session ref_count that was added as a workaround for this bug, since it is no longer needed.
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…ions (zed-industries#53859) `AgentPanel::open_thread` (called when clicking `@thread` mention links, pasting thread links, or opening threads via the CLI) was calling `external_thread` directly, bypassing the de-duplication guards in `load_agent_thread`. This meant clicking a thread link to the currently-active thread would create a redundant `ConversationView` sharing the same `NativeAgent` session. When the old CV was later evicted from `background_threads`, its `on_release` called `close_all_sessions`, removing the session and breaking the surviving CV with "Session not found". Fix this by routing `open_thread` through `load_agent_thread`, which checks the active view, retained threads, and background threads before creating a new `ConversationView`. This prevents the duplicate from being created in the first place. Release Notes: - Fixed a "Session not found" error that could occur after clicking a thread mention link.
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AgentPanel::open_thread(called when clicking@threadmention links, pasting thread links, or opening threads via the CLI) was callingexternal_threaddirectly, bypassing the de-duplication guards inload_agent_thread. This meant clicking a thread link to the currently-active thread would create a redundantConversationViewsharing the sameNativeAgentsession. When the old CV was later evicted frombackground_threads, itson_releasecalledclose_all_sessions, removing the session and breaking the surviving CV with "Session not found".Fix this by routing
open_threadthroughload_agent_thread, which checks the active view, retained threads, and background threads before creating a newConversationView. This prevents the duplicate from being created in the first place.Release Notes: