fix(renderer): fix subscriptions memory leak

When closing the chat panel subscriptions were not cleaned properly

This led to leak in subscriptions callback and also led to renderer for the same events

Performance was degrading over time.

Author: sudo-tee

lua/opencode/ui/renderer.lua

@@ -54,10 +54,14 @@ function M.reset()
   trigger_on_data_rendered()
 end
 
+M.on_session_idle = function()
+  vim.notify('Session is idle, no-op')
+end
+
 ---Set up event subscriptions
 ---@param subscribe? boolean false to unsubscribe
 function M.setup_subscriptions(subscribe)
-  subscribe = subscribe or true
+  subscribe = subscribe == nil and true or subscribe
 
   if subscribe then
     state.subscribe('is_opencode_focused', M.on_focus_changed)
@@ -75,6 +79,7 @@ function M.setup_subscriptions(subscribe)
     { 'session.updated', M.on_session_updated },
     { 'session.compacted', M.on_session_compacted },
     { 'session.error', M.on_session_error },
+    { 'session.idle', M.on_session_idle },
     { 'message.updated', M.on_message_updated },
     { 'message.removed', M.on_message_removed },
     { 'message.part.updated', M.on_part_updated },
@@ -132,8 +137,6 @@ function M._render_full_session_data(session_data)
 
   local revert_index = nil
 
-  -- local event_manager = state.event_manager
-
   -- if we're loading a session and there's no currently selected model, set it
   -- from the messages
   local set_mode_from_messages = not state.current_model
@@ -143,11 +146,9 @@ function M._render_full_session_data(session_data)
       revert_index = i
     end
 
-    -- table.insert(event_manager.captured_events, { type = 'message.updated', properties = { info = msg.info } })
     M.on_message_updated({ info = msg.info }, revert_index)
 
     for _, part in ipairs(msg.parts or {}) do
-      -- table.insert(event_manager.captured_events, { type = 'message.part.updated', properties = { part = part } })
       M.on_part_updated({ part = part }, revert_index)
     end
   end

tests/replay/renderer_spec.lua

@@ -91,7 +91,61 @@ local function assert_output_matches(expected, actual, name)
   end
 end
 
-describe('renderer', function()
+describe('renderer unit tests', function()
+  local event_subscriptions = {
+    'session.updated',
+    'session.compacted',
+    'session.error',
+    'session.idle',
+    'message.updated',
+    'message.removed',
+    'message.part.updated',
+    'message.part.removed',
+    'permission.updated',
+    'permission.replied',
+    'file.edited',
+    'custom.restore_point.created',
+    'custom.emit_events.finished',
+  }
+
+  before_each(function()
+    require('opencode.event_manager').setup()
+  end)
+
+  it('subsribes to events correctly', function()
+    local renderer = require('opencode.ui.renderer')
+    local event_manager = state.event_manager
+
+    event_manager.events = {}
+
+    renderer.setup_subscriptions()
+
+    for _, event_name in ipairs(event_subscriptions) do
+      assert.is_true(
+        event_manager.events[event_name] ~= nil,
+        string.format('Renderer did not subscribe to event: %s', event_name)
+      )
+    end
+  end)
+
+  it('unsubsribes from events correctly', function()
+    local renderer = require('opencode.ui.renderer')
+    local event_manager = state.event_manager
+
+    renderer.setup_subscriptions()
+
+    renderer.setup_subscriptions(false)
+
+    for _, event_name in ipairs(event_subscriptions) do
+      assert.is_true(
+        vim.tbl_isempty(event_manager.events[event_name]),
+        string.format('Renderer did not unsubscribe from event: %s', event_name)
+      )
+    end
+  end)
+end)
+
+describe('renderer functional tests', function()
   config.debug.show_ids = true
 
   before_each(function()