perf: cache parsed symbol snapshots to avoid redundant tree-sitter parses

lua/opencode/lru_cache.lua

@@ -0,0 +1,59 @@
+---@generic T
+---@class LruCache<T>
+---@field private capacity integer
+---@field private entries table<any, { value: T, used: integer }>
+---@field private size integer
+---@field private clock integer
+local LruCache = {}
+LruCache.__index = LruCache
+
+---@param capacity integer
+---@return LruCache<T>
+function LruCache.new(capacity)
+  assert(capacity > 0, 'cache capacity must be positive')
+  return setmetatable({
+    capacity = capacity,
+    entries = {},
+    size = 0,
+    clock = 0,
+  }, LruCache)
+end
+
+---@param key any
+---@return T
+function LruCache:get(key)
+  local entry = self.entries[key]
+  if not entry then
+    return nil
+  end
+
+  self.clock = self.clock + 1
+  entry.used = self.clock
+  return entry.value
+end
+
+---@param key any
+---@param value T
+function LruCache:set(key, value)
+  local entry = self.entries[key]
+  if not entry and self.size >= self.capacity then
+    local oldest_key
+    local oldest_use = math.huge
+    for cached_key, cached_entry in pairs(self.entries) do
+      if cached_entry.used < oldest_use then
+        oldest_key = cached_key
+        oldest_use = cached_entry.used
+      end
+    end
+    self.entries[oldest_key] = nil
+    self.size = self.size - 1
+  end
+
+  if not entry then
+    self.size = self.size + 1
+  end
+  self.clock = self.clock + 1
+  self.entries[key] = { value = value, used = self.clock }
+end
+
+return LruCache

lua/opencode/types.lua

@@ -569,6 +569,7 @@
 
 ---@class FormatterContext
 ---@field interactive boolean
+---@field resolve_symbol_targets? boolean
 ---@field get_child_parts? fun(session_id: string): OpencodeMessagePart[]?
 ---@field current_refs? CodeReference[]
 ---@field current_files? string[]

lua/opencode/ui/formatter.lua

@@ -795,7 +795,7 @@ local function add_file_reference_targets(output, rendered, rendered_reference_r
 end
 
 local function add_symbol_reference_targets(output, rendered, rendered_mention_ranges, first_line_idx, context)
-  if not (context and context.interactive and context.symbol_cycle) then
+  if not (context and context.interactive and context.resolve_symbol_targets ~= false and context.symbol_cycle) then
     return {}
   end
 

lua/opencode/ui/renderer.lua

@@ -283,7 +283,6 @@ function M.event_subscriptions()
     { 'file.edited', events.on_file_edited },
     { 'file.watcher.updated', events.on_file_watcher_updated },
     { 'custom.restore_point.created', events.on_restore_points },
-    { 'custom.emit_events.finished', M.on_emit_events_finished },
   }
 end
 
@@ -422,10 +421,10 @@ function M._render_full_session_data(session_data, opts)
     events.on_part_updated({ part = revert_message.parts[1] })
   end
 
-  local t_format_end = vim.uv.hrtime()
   flush.flush()
   flush.end_bulk_mode()
-  local t_flush_end = vim.uv.hrtime()
+
+  events.refresh_rendered_symbol_targets()
 
   if opts.restore_model_from_messages then
     require('opencode.services.agent_model').initialize_current_model({ restore_from_messages = true })
@@ -600,11 +599,6 @@ end
 M.reconcile_rendered_message_limit = reconcile_rendered_message_limit
 M.is_message_visible = is_message_visible
 
----Scroll to bottom after all queued events have been processed
-function M.on_emit_events_finished()
-  M.scroll_to_bottom()
-end
-
 ---Return all actions available at a given (0-indexed) line
 ---@param line integer
 ---@return table[]

lua/opencode/ui/renderer/events.lua

@@ -104,6 +104,7 @@ local function mark_rendered_assistant_text_parts_dirty()
       local message_data = ctx.render_state:get_message(part_data.message_id)
       local message = message_data and message_data.message or find_message_in_state(part_data.message_id)
       if is_assistant_message(message) and message.info.sessionID == active_session_id then
+        ctx.formatted_parts[part_id] = nil
         flush.mark_part_dirty(part_id, part_data.message_id)
       end
     end
@@ -118,6 +119,11 @@ end
 
 local M = {}
 
+function M.refresh_rendered_symbol_targets()
+  reference_facts.refresh_current_files()
+  mark_rendered_assistant_text_parts_dirty()
+end
+
 function M.invalidate_reference_targets_for_file_change()
   reference_facts.refresh_current_files()
   mark_rendered_assistant_text_parts_dirty()

lua/opencode/ui/renderer/flush.lua

@@ -14,9 +14,7 @@ local warned_part_render_error = false
 
 local function output_window_is_in_background_tab()
   local output_win = state.windows and state.windows.output_win
-  return output_win
-    and vim.api.nvim_win_is_valid(output_win)
-    and not state.ui.is_window_in_current_tab(output_win)
+  return output_win and vim.api.nvim_win_is_valid(output_win) and not state.ui.is_window_in_current_tab(output_win)
 end
 
 ---@param part_id string
@@ -251,6 +249,7 @@ end
 local function new_formatter_context()
   return {
     interactive = true,
+    resolve_symbol_targets = not ctx.bulk_mode,
     get_child_parts = function(session_id)
       return ctx.render_state:get_child_session_parts(session_id)
     end,
@@ -543,6 +542,7 @@ function M.resume_deferred_rendering()
   M.flush()
   if ctx.bulk_mode then
     M.end_bulk_mode()
+    require('opencode.ui.renderer.events').refresh_rendered_symbol_targets()
   end
   M.flush_pending_on_data_rendered()
 end

lua/opencode/ui/symbol_snapshot.lua

@@ -1,6 +1,35 @@
 local M = {}
 
 local MIN_DEFINITION_TOKEN_LENGTH = 2
+local path_cache = require('opencode.lru_cache').new(256)
+
+local function timestamp_key(timestamp)
+  if type(timestamp) == 'table' then
+    return string.format('%s:%s', timestamp.sec or '', timestamp.nsec or '')
+  end
+  return tostring(timestamp or '')
+end
+
+local function source_version(path)
+  local bufnr = vim.fn.bufnr and vim.fn.bufnr(path) or -1
+  if bufnr and bufnr > 0 and vim.api.nvim_buf_is_loaded and vim.api.nvim_buf_is_loaded(bufnr) then
+    local ok, changedtick = pcall(vim.api.nvim_buf_get_changedtick, bufnr)
+    return ok and 'buffer:' .. bufnr .. ':' .. changedtick or nil
+  end
+
+  local stat = (vim.uv or vim.loop).fs_stat(path)
+  if not stat then
+    return nil
+  end
+  return table.concat({
+    'disk',
+    stat.dev or '',
+    stat.ino or '',
+    timestamp_key(stat.mtime),
+    timestamp_key(stat.ctime),
+    stat.size,
+  }, ':')
+end
 
 local function absolute_path(path)
   if path:sub(1, 1) == '/' then
@@ -126,6 +155,13 @@ local function collect_path(path)
     lang = parser_lang
   end
 
+  local version = source_version(path)
+  local cache_key = version and lang .. ':' .. version
+  local cached = path_cache:get(path)
+  if cached and cached.version == cache_key then
+    return cached.by_token
+  end
+
   local query_ok, query = pcall(function()
     if vim.treesitter and vim.treesitter.query and vim.treesitter.query.get then
       return vim.treesitter.query.get(lang, 'locals')
@@ -170,6 +206,10 @@ local function collect_path(path)
     end
   end
 
+  if cache_key then
+    path_cache:set(path, { version = cache_key, by_token = by_token })
+  end
+
   return by_token
 end
 

tests/replay/renderer_spec.lua

@@ -214,6 +214,10 @@ describe('renderer unit tests', function()
     }))
   end)
 
+  it('leaves post-flush scrolling to the renderer flush', function()
+    assert.is_false(vim.tbl_contains(event_subscriptions(), 'custom.emit_events.finished'))
+  end)
+
   it('unsubsribes from events correctly', function()
     local renderer = require('opencode.ui.renderer')
     local event_manager = state.event_manager
@@ -503,7 +507,15 @@ describe('renderer unit tests', function()
       return original_filereadable(path)
     end
     state.session.set_active(helpers.get_session_from_events(events, true))
+    vim.wait(0)
     renderer._render_full_session_data(helpers.load_session_from_events(events))
+    local ctx = require('opencode.ui.renderer.ctx')
+    assert.is_true(
+      vim.wait(1000, function()
+        return not ctx:has_pending_work()
+      end),
+      'Timed out waiting for deferred symbol targets'
+    )
 
     local actual = helpers.capture_output(state.windows.output_buf, output_window.namespace)
     local symbol_mark

tests/unit/lru_cache_spec.lua

@@ -0,0 +1,27 @@
+local LruCache = require('opencode.lru_cache')
+
+describe('LRU cache', function()
+  it('evicts the least recently used entry', function()
+    local cache = LruCache.new(2)
+    cache:set('first', 1)
+    cache:set('second', 2)
+    assert.equal(1, cache:get('first'))
+
+    cache:set('third', 3)
+
+    assert.is_nil(cache:get('second'))
+    assert.equal(1, cache:get('first'))
+    assert.equal(3, cache:get('third'))
+  end)
+
+  it('updates existing entries without evicting another entry', function()
+    local cache = LruCache.new(2)
+    cache:set('first', 1)
+    cache:set('second', 2)
+
+    cache:set('first', 3)
+
+    assert.equal(3, cache:get('first'))
+    assert.equal(2, cache:get('second'))
+  end)
+end)

tests/unit/persist_state_spec.lua

@@ -112,6 +112,7 @@ describe('persist_state', function()
     vim.fn.writefile(lines or { 'line 1', 'line 2', 'line 3', 'line 4', 'line 5' }, tmpfile)
 
     code_buf = vim.fn.bufadd(tmpfile)
+    vim.bo[code_buf].swapfile = false
     vim.fn.bufload(code_buf)
     vim.bo[code_buf].buflisted = true
 

tests/unit/symbol_snapshot_spec.lua

@@ -7,14 +7,19 @@ describe('opencode.ui.symbol_snapshot', function()
   local original_filetype
   local original_treesitter
   local original_notify
+  local original_uv
+  local original_loop
+  local original_lru_cache
   local files
+  local file_versions
   local buffers
   local captures_by_content
   local read_counts
   local parse_counts
   local query_available
   local parser_available
   local notify_calls
+  local cached_paths
 
   local function fake_node(text, row, col)
     return {
@@ -27,6 +32,7 @@ describe('opencode.ui.symbol_snapshot', function()
 
   local function set_file(path, lines, captures)
     files[path] = lines
+    file_versions[path] = (file_versions[path] or 0) + 1
     captures_by_content[table.concat(lines, '\n')] = captures or {}
   end
 
@@ -36,14 +42,19 @@ describe('opencode.ui.symbol_snapshot', function()
     original_filetype = vim.filetype
     original_treesitter = vim.treesitter
     original_notify = vim.notify
+    original_uv = vim.uv
+    original_loop = vim.loop
+    original_lru_cache = package.loaded['opencode.lru_cache']
     files = {}
+    file_versions = {}
     buffers = {}
     captures_by_content = {}
     read_counts = {}
     parse_counts = {}
     query_available = true
     parser_available = true
     notify_calls = {}
+    cached_paths = {}
 
     vim.fn = vim.tbl_extend('force', vim.fn or {}, {
       getcwd = function()
@@ -175,6 +186,27 @@ describe('opencode.ui.symbol_snapshot', function()
       table.insert(notify_calls, { msg = msg, level = level })
     end
 
+    local uv = {
+      fs_stat = function(path)
+        local version = file_versions[path]
+        return version and { mtime = { sec = version, nsec = 0 }, size = #table.concat(files[path], '\n') } or nil
+      end,
+    }
+    vim.uv = uv
+    vim.loop = uv
+
+    package.loaded['opencode.lru_cache'] = {
+      new = function()
+        return {
+          get = function(_, path)
+            return cached_paths[path]
+          end,
+          set = function(_, path, value)
+            cached_paths[path] = value
+          end,
+        }
+      end,
+    }
     package.loaded['opencode.ui.symbol_snapshot'] = nil
     symbol_snapshot = require('opencode.ui.symbol_snapshot')
   end)
@@ -185,7 +217,10 @@ describe('opencode.ui.symbol_snapshot', function()
     vim.filetype = original_filetype
     vim.treesitter = original_treesitter
     vim.notify = original_notify
+    vim.uv = original_uv
+    vim.loop = original_loop
     package.loaded['opencode.ui.symbol_snapshot'] = nil
+    package.loaded['opencode.lru_cache'] = original_lru_cache
   end)
 
   it('exports only the frozen public API', function()
@@ -246,6 +281,28 @@ describe('opencode.ui.symbol_snapshot', function()
     assert.equal(1, parse_counts[content])
   end)
 
+  it('reuses parsed candidate files across cycles until they change', function()
+    local path = '/test/project/src/main.lua'
+    local content = 'local function foo() end'
+    set_file(path, { content }, {
+      { id = 1, node = fake_node('foo', 0, 15) },
+    })
+
+    local first = symbol_snapshot.new_cycle()
+    local second = symbol_snapshot.new_cycle()
+    assert.equal(1, #symbol_snapshot.targets_for_token(first, 'foo', { path }))
+    assert.equal(1, #symbol_snapshot.targets_for_token(second, 'foo', { path }))
+    assert.equal(1, read_counts[path])
+    assert.equal(1, parse_counts[content])
+
+    set_file(path, { 'local function bar() end' }, {
+      { id = 1, node = fake_node('bar', 0, 15) },
+    })
+    local changed = symbol_snapshot.new_cycle()
+    assert.equal(1, #symbol_snapshot.targets_for_token(changed, 'bar', { path }))
+    assert.equal(2, read_counts[path])
+  end)
+
   it('collects definition tokens from referenced readable Lua files', function()
     set_file('/test/project/src/main.lua', { 'local function foo() end' }, {
       { id = 1, node = fake_node('foo', 0, 15) },