fix: markdown flashing when updating parts

Author: sudo-tee

lua/opencode/ui/renderer.lua

@@ -11,8 +11,6 @@ local scheduler = require('opencode.ui.renderer.scheduler')
 
 local M = {}
 
-local trigger_on_data_rendered
-
 local function with_suppressed_scroll_tracking(fn)
   return output_window.with_suppressed_scroll_tracking(fn)
 end
@@ -71,32 +69,15 @@ local function apply_render_plan(render_plan, should_scroll)
     return true
   end
 
-  trigger_on_data_rendered()
+  M.trigger_on_data_rendered()
   return true
 end
 
 -- Expose event handlers on M so tests can call them directly and subscriptions
 -- can be stubbed cleanly (e.g. stub(renderer, '_render_full_session_data'))
 M.on_session_updated = events.on_session_updated
 
-trigger_on_data_rendered = require('opencode.util').debounce(function()
-  local cb_type = type(config.ui.output.rendering.on_data_rendered)
-  if cb_type == 'boolean' then
-    return
-  end
-  if not state.windows or not state.windows.output_buf or not state.windows.output_win then
-    return
-  end
-  if cb_type == 'function' then
-    pcall(config.ui.output.rendering.on_data_rendered, state.windows.output_buf, state.windows.output_win)
-  elseif vim.fn.exists(':RenderMarkdown') > 0 then
-    vim.cmd(':RenderMarkdown')
-  elseif vim.fn.exists(':Markview') > 0 then
-    vim.cmd(':Markview render ' .. state.windows.output_buf)
-  end
-end, config.ui.output.rendering.markdown_debounce_ms or 250)
-
-local function trigger_on_data_rendered_now()
+local function invoke_on_data_rendered()
   local cb_type = type(config.ui.output.rendering.on_data_rendered)
   if cb_type == 'boolean' then
     return
@@ -113,8 +94,13 @@ local function trigger_on_data_rendered_now()
   end
 end
 
+M.trigger_on_data_rendered =
+  require('opencode.util').debounce(invoke_on_data_rendered, config.ui.output.rendering.markdown_debounce_ms or 250)
+
 ---Reset all renderer state and clear the output buffer
-function M.reset()
+---@param opts? { trigger_on_data_rendered?: boolean }
+function M.reset(opts)
+  opts = opts or {}
   ctx:reset()
   output_window.clear()
 
@@ -127,7 +113,9 @@ function M.reset()
   permission_window.clear_all()
   state.renderer.reset()
 
-  trigger_on_data_rendered_now()
+  if opts.trigger_on_data_rendered ~= false then
+    invoke_on_data_rendered()
+  end
 end
 
 ---Unsubscribe from all events and reset
@@ -154,22 +142,22 @@ function M.setup_subscriptions(subscribe)
   end
 
   local subs = {
-    { 'session.updated',               events.on_session_updated },
-    { 'session.compacted',             events.on_session_compacted },
-    { 'session.error',                 events.on_session_error },
-    { 'message.updated',               events.on_message_updated },
-    { 'message.removed',               events.on_message_removed },
-    { 'message.part.updated',          events.on_part_updated },
-    { 'message.part.removed',          events.on_part_removed },
-    { 'permission.updated',            events.on_permission_updated },
-    { 'permission.asked',              events.on_permission_updated },
-    { 'permission.replied',            events.on_permission_replied },
-    { 'question.asked',                events.on_question_asked },
-    { 'question.replied',              events.clear_question_display },
-    { 'question.rejected',             events.clear_question_display },
-    { 'file.edited',                   events.on_file_edited },
-    { 'custom.restore_point.created',  events.on_restore_points },
-    { 'custom.emit_events.finished',   M.on_emit_events_finished },
+    { 'session.updated', events.on_session_updated },
+    { 'session.compacted', events.on_session_compacted },
+    { 'session.error', events.on_session_error },
+    { 'message.updated', events.on_message_updated },
+    { 'message.removed', events.on_message_removed },
+    { 'message.part.updated', events.on_part_updated },
+    { 'message.part.removed', events.on_part_removed },
+    { 'permission.updated', events.on_permission_updated },
+    { 'permission.asked', events.on_permission_updated },
+    { 'permission.replied', events.on_permission_replied },
+    { 'question.asked', events.on_question_asked },
+    { 'question.replied', events.clear_question_display },
+    { 'question.rejected', events.clear_question_display },
+    { 'file.edited', events.on_file_edited },
+    { 'custom.restore_point.created', events.on_restore_points },
+    { 'custom.emit_events.finished', M.on_emit_events_finished },
   }
 
   for _, sub in ipairs(subs) do
@@ -214,7 +202,7 @@ end
 ---Called after a full session fetch or when revert state changes
 ---@param session_data OpencodeMessage[]
 function M._render_full_session_data(session_data)
-  M.reset()
+  M.reset({ trigger_on_data_rendered = false })
 
   if not state.active_session then
     return
@@ -308,15 +296,13 @@ function M.scroll_to_bottom(force)
   local prev_line_count = ctx.prev_line_count
   ctx.prev_line_count = line_count
 
-  trigger_on_data_rendered()
-
   local should_scroll = force
     or prev_line_count == 0
     or config.ui.output.always_scroll_to_bottom
     or (function()
-          local ok_cursor, cursor = pcall(vim.api.nvim_win_get_cursor, output_win)
-          return ok_cursor and cursor and (cursor[1] >= prev_line_count or cursor[1] >= line_count)
-        end)()
+      local ok_cursor, cursor = pcall(vim.api.nvim_win_get_cursor, output_win)
+      return ok_cursor and cursor and (cursor[1] >= prev_line_count or cursor[1] >= line_count)
+    end)()
 
   if should_scroll then
     with_suppressed_scroll_tracking(function()
@@ -328,7 +314,7 @@ function M.scroll_to_bottom(force)
     end)
   end
 
-  trigger_on_data_rendered()
+  M.trigger_on_data_rendered()
 end
 
 ---Re-render the permission display when focus changes (updates shortcut hints)
@@ -345,11 +331,11 @@ function M.on_session_changed(_, new, old)
     return
   end
 
-   if new and ctx.last_rendered_session_id == new.id and state.messages ~= nil then
+  if new and ctx.last_rendered_session_id == new.id and state.messages ~= nil then
     return
   end
 
-  M.reset()
+  M.reset({ trigger_on_data_rendered = not new })
   if new then
     M.render_full_session()
   end

lua/opencode/ui/renderer/buffer_ops.lua

@@ -179,7 +179,7 @@ local function apply_changed_line_patches(previous_output, next_output)
 
   if output_window.buffer_valid() then
     output_window.begin_update()
-    output_window.clear_extmarks(0, -1, true)
+    output_window.clear_extmarks(0, -1)
     for _, patch in ipairs(patches) do
       local start_line = patch.old_start_line + line_delta
       local old_end_line_exclusive = patch.old_end_line_exclusive + line_delta
@@ -216,7 +216,7 @@ local function apply_block_patch(visible_render, patch)
 
   if output_window.buffer_valid() then
     output_window.begin_update()
-    output_window.clear_extmarks(patch.start_line, patch.old_end_line_exclusive, true)
+    output_window.clear_extmarks(patch.start_line, patch.old_end_line_exclusive)
     output_window.set_lines(replacement.lines or {}, patch.start_line, patch.old_end_line_exclusive)
     output_window.set_extmarks(replacement.extmarks, patch.start_line)
     output_window.end_update()

lua/opencode/util.lua

@@ -348,7 +348,9 @@ function M.debounce(func, delay)
     end
     local args = { ... }
     timer = vim.defer_fn(function()
-      func(unpack(args))
+      vim.schedule(function()
+        func(unpack(args))
+      end)
     end, delay or 100)
   end
 end

tests/unit/renderer/backend_spec.lua tests/unit/renderer/buffer_ops_spec.luatests/unit/renderer/backend_spec.lua renamed to tests/unit/renderer/buffer_ops_spec.lua

@@ -3,7 +3,7 @@ local backend = require('opencode.ui.renderer.buffer_ops')
 local ctx = require('opencode.ui.renderer.ctx')
 local state = require('opencode.state')
 
-describe('renderer backend', function()
+describe('renderer buffer_ops', function()
   local original_set_lines
   local original_clear_extmarks
   local original_set_extmarks
@@ -224,7 +224,7 @@ describe('renderer backend', function()
 
     assert.same({ 'same', 'changed', 'same', '' }, output.lines)
     assert.same('begin', calls[1])
-    assert.same({ 'clear', 1, 2, true }, calls[2])
+    assert.same({ 'clear', 1, 2 }, calls[2])
     assert.same({ 'lines', { 'changed' }, 1, 2 }, calls[3])
     assert.same({ 'extmarks', {}, 1 }, calls[4])
     assert.same('end', calls[5])
@@ -282,7 +282,7 @@ describe('renderer backend', function()
 
     assert.same({ 'header', 'new body', 'footer', '' }, output.lines)
     assert.same('begin', calls[1])
-    assert.same({ 'clear', 0, -1, true }, calls[2])
+    assert.same({ 'clear', 0, -1 }, calls[2])
     assert.same({ 'lines', { 'new body' }, 1, 2 }, calls[3])
     assert.same({ 'extmarks', {}, nil }, calls[4])
     assert.same('end', calls[5])