feat(dap): show debug adapter progress natively and keep it alive

lua/flutter-tools/devices.lua

@@ -6,7 +6,6 @@ local commands = lazy.require("flutter-tools.commands") ---@module "flutter-tool
 local executable = lazy.require("flutter-tools.executable") ---@module "flutter-tools.executable"
 local config = lazy.require("flutter-tools.config") ---@module "flutter-tools.config"
 local fmt = string.format
-local api = vim.api
 
 ---@alias Device {name: string, id: string, platform: string, system: string, type: integer, cold_boot: boolean}
 
@@ -175,19 +174,9 @@ end
 ---@param title string
 ---@return fun(status: "success"|"failed")
 local function start_progress(title)
-  if vim.fn.has("nvim-0.12") == 0 then
-    return function() end
-  end
-  local opts = { kind = "progress", source = "flutter-tools", title = title, status = "running" }
-  local id = api.nvim_echo({ { "Loading" } }, false, opts)
-  return function(status)
-    local message = status == "success" and "Done" or "Failed"
-    api.nvim_echo(
-      { { message } },
-      false,
-      vim.tbl_extend("force", opts, { id = id, status = status })
-    )
-  end
+  local progress = ui.progress(title)
+  progress:report("Loading", "running")
+  return function(status) progress:report(status == "success" and "Done" or "Failed", status) end
 end
 
 -----------------------------------------------------------------------------//

lua/flutter-tools/runners/debugger_runner.lua

@@ -167,8 +167,21 @@ local function handle_inspect_event(isolate_id)
   end)
 end
 
+---@type table<string, flutter.Progress>
+local active_progress = {}
+
+local function end_all_progress()
+  for progress_id, progress in pairs(active_progress) do
+    progress:report("Stopped", "failed")
+    active_progress[progress_id] = nil
+  end
+end
+
 local listened_events = {
   { "after", "event_output" },
+  { "before", "event_progressStart" },
+  { "before", "event_progressUpdate" },
+  { "before", "event_progressEnd" },
   { "before", "event_exited" },
   { "before", "event_terminated" },
   { "before", "event_app.started" },
@@ -197,7 +210,24 @@ local function register_dap_listeners(on_run_data, on_run_exit)
     end
   end
 
+  dap.listeners.before["event_progressStart"][plugin_identifier] = function(_, body)
+    local progress = active_progress[body.progressId] or ui.progress(body.title)
+    active_progress[body.progressId] = progress
+    progress:report(body.message, "running", { percent = body.percentage })
+  end
+  dap.listeners.before["event_progressUpdate"][plugin_identifier] = function(_, body)
+    local progress = active_progress[body.progressId]
+    if progress then progress:report(body.message, "running", { percent = body.percentage }) end
+  end
+  dap.listeners.before["event_progressEnd"][plugin_identifier] = function(_, body)
+    local progress = active_progress[body.progressId]
+    if not progress then return end
+    progress:report(body.message or "Done", "success")
+    active_progress[body.progressId] = nil
+  end
+
   local handle_termination = function()
+    end_all_progress()
     if next(before_start_logs) ~= nil then on_run_exit(before_start_logs) end
     if vm_service.is_connected() then vm_service.disconnect() end
   end
@@ -271,6 +301,7 @@ dap.listeners.on_session[plugin_identifier] = function(_, session)
     return
   end
   tracked_session_id = session.id
+  session.on_close[plugin_identifier] = end_all_progress
   local listeners = pending_listeners or get_untracked_session_listeners()
   pending_listeners = nil
   if listeners then

lua/flutter-tools/ui.lua

@@ -140,4 +140,66 @@ function M.open_win(opts, on_open)
   end
 end
 
+M.progress_timing = {
+  -- Ghostty drops an OSC 9;4 progress bar after 15s without an update.
+  keepalive_ms = 10000,
+  -- Give up on a progress with no real update in this long, so a hung or crashed process cannot
+  -- keep the bar alive forever.
+  stall_ms = 2 * 60 * 1000,
+}
+
+---@alias flutter.ProgressStatus "running"|"success"|"failed"
+
+---@class flutter.Progress
+---@field report fun(self: flutter.Progress, message: string?, status: flutter.ProgressStatus, opts: {percent?: number, history?: boolean}?)
+
+---A native progress message (Neovim 0.12+) that stays visible in terminals which expire idle
+---progress bars. Reporting keeps one message id, so later reports update it in place.
+---@param title string
+---@return flutter.Progress
+function M.progress(title)
+  if vim.fn.has("nvim-0.12") == 0 then return { report = function() end } end
+  local id, message, percent, timer
+  local last_update = 0
+
+  local function stop_keepalive()
+    if not timer then return end
+    timer:stop()
+    timer:close()
+    timer = nil
+  end
+
+  local function echo(status, history)
+    id = api.nvim_echo({ { message or title } }, history or false, {
+      id = id,
+      kind = "progress",
+      source = "flutter-tools",
+      title = title,
+      status = status,
+      percent = percent,
+    })
+  end
+
+  local function keepalive()
+    if not timer then return end
+    if vim.uv.now() - last_update > M.progress_timing.stall_ms then return stop_keepalive() end
+    echo("running")
+  end
+
+  return {
+    report = function(_, new_message, status, opts)
+      opts = opts or {}
+      message = new_message or message
+      percent = opts.percent and math.floor(opts.percent)
+      last_update = vim.uv.now()
+      echo(status, opts.history)
+      if status ~= "running" then return stop_keepalive() end
+      if timer then return end
+      timer = assert(vim.uv.new_timer())
+      local interval = M.progress_timing.keepalive_ms
+      timer:start(interval, interval, vim.schedule_wrap(keepalive))
+    end,
+  }
+end
+
 return M

lua/flutter-tools/widget_preview.lua

@@ -23,7 +23,7 @@ local OUTPUT_LINES_ON_FAILURE = 15
 ---@field cancelled boolean
 ---@field output string[] recent output, shown if the previewer fails
 ---@field dir string
----@field progress_id (integer|string)?
+---@field progress flutter.Progress
 
 ---@type flutter.WidgetPreviewState?
 local state = nil
@@ -58,13 +58,7 @@ end
 ---@param message string
 ---@param status "running"|"success"|"failed"
 local function report(current, message, status)
-  current.progress_id = api.nvim_echo({ { message } }, status ~= "running", {
-    id = current.progress_id,
-    kind = "progress",
-    source = "flutter-tools",
-    title = "Widget preview",
-    status = status,
-  })
+  current.progress:report(message, status, { history = status ~= "running" })
 end
 
 ---@param current flutter.WidgetPreviewState
@@ -208,7 +202,13 @@ function M.show(dir)
   if not project_dir then return ui.notify("Unable to find a Flutter project", ui.ERROR) end
 
   ---@type flutter.WidgetPreviewState
-  local current = { started = false, cancelled = false, output = {}, dir = project_dir }
+  local current = {
+    started = false,
+    cancelled = false,
+    output = {},
+    dir = project_dir,
+    progress = ui.progress("Widget preview"),
+  }
   state = current
   report(current, "Starting", "running")
   dtd.start(function(err)

tests/debugger_runner_spec.lua

@@ -17,6 +17,9 @@ describe("debugger runner", function()
     dap.adapters.dart = nil
     dap.configurations.dart = nil
     dap.listeners.after["event_output"]["flutter-tools"] = nil
+    for _, event in ipairs({ "event_progressStart", "event_progressUpdate", "event_progressEnd" }) do
+      dap.listeners.before[event]["flutter-tools"] = nil
+    end
     runner.on_untracked_session(function() end)
     package.loaded["flutter-tools.runners.debugger_runner"] = nil
   end)
@@ -57,7 +60,10 @@ describe("debugger runner", function()
       }
     end)
 
-    dap.listeners.on_session["flutter-tools"](nil, { id = 1, config = { type = "dart" } })
+    dap.listeners.on_session["flutter-tools"](
+      nil,
+      { id = 1, config = { type = "dart" }, on_close = {} }
+    )
     dap.listeners.after["event_output"]["flutter-tools"](nil, {
       category = "stderr",
       output = "first\nsecond",
@@ -74,4 +80,59 @@ describe("debugger runner", function()
 
     assert.is_false(called)
   end)
+
+  it("reports adapter progress as native progress messages", function()
+    local reported = {}
+    local autocmd = vim.api.nvim_create_autocmd("Progress", {
+      callback = function(ev)
+        table.insert(reported, { ev.data.title, ev.data.status, ev.data.percent })
+      end,
+    })
+    runner.on_untracked_session(function()
+      return { on_run_data = function() end, on_run_exit = function() end }
+    end)
+    dap.listeners.on_session["flutter-tools"](
+      nil,
+      { id = 3, config = { type = "dart" }, on_close = {} }
+    )
+
+    local before = dap.listeners.before
+    before["event_progressStart"]["flutter-tools"](nil, {
+      progressId = "launch",
+      title = "Flutter",
+      message = "Launching…",
+    })
+    before["event_progressUpdate"]["flutter-tools"](nil, { progressId = "launch", percentage = 50 })
+    before["event_progressUpdate"]["flutter-tools"](nil, { progressId = "unknown", message = "x" })
+    before["event_progressEnd"]["flutter-tools"](nil, { progressId = "launch" })
+    vim.api.nvim_del_autocmd(autocmd)
+
+    assert.are.same({
+      { "Flutter", "running" },
+      { "Flutter", "running", 50 },
+      { "Flutter", "success" },
+    }, reported)
+  end)
+
+  it("fails running progress when the session closes without ending it", function()
+    local statuses = {}
+    local autocmd = vim.api.nvim_create_autocmd("Progress", {
+      callback = function(ev) table.insert(statuses, ev.data.status) end,
+    })
+    runner.on_untracked_session(function()
+      return { on_run_data = function() end, on_run_exit = function() end }
+    end)
+    local session = { id = 4, config = { type = "dart" }, on_close = {} }
+    dap.listeners.on_session["flutter-tools"](nil, session)
+
+    dap.listeners.before["event_progressStart"]["flutter-tools"](nil, {
+      progressId = "launch",
+      title = "Flutter",
+      message = "Launching…",
+    })
+    session.on_close["flutter-tools"](session)
+    vim.api.nvim_del_autocmd(autocmd)
+
+    assert.are.same({ "running", "failed" }, statuses)
+  end)
 end)

tests/devices_spec.lua

@@ -177,6 +177,9 @@ INFO    | Storing crashdata in: /tmp/android-ts/emu-crash-34.2.14.db, detection
         notify = function(msg, level)
           if msg ~= "" then table.insert(notifications, { msg = msg, level = level }) end
         end,
+        progress = function()
+          return { report = function() end }
+        end,
       }
       package.loaded["plenary.job"] = {
         new = function(_, opts)

tests/ui_spec.lua

@@ -0,0 +1,47 @@
+describe("ui.progress", function()
+  local ui
+  local original_timing
+  local events
+  local autocmd
+
+  before_each(function()
+    ui = require("flutter-tools.ui")
+    original_timing = ui.progress_timing
+    events = {}
+    autocmd = vim.api.nvim_create_autocmd("Progress", {
+      callback = function(ev) table.insert(events, { ev.data.status, ev.data.percent }) end,
+    })
+  end)
+
+  after_each(function()
+    ui.progress_timing = original_timing
+    vim.api.nvim_del_autocmd(autocmd)
+  end)
+
+  it("resends a running progress so terminals keep the bar", function()
+    ui.progress_timing = { keepalive_ms = 10, stall_ms = 60000 }
+    local progress = ui.progress("Test")
+
+    progress:report("Working", "running", { percent = 40 })
+    vim.wait(100, function() return #events >= 3 end)
+    progress:report("Done", "success")
+    local count = #events
+    vim.wait(50)
+
+    assert.is_true(count >= 4)
+    assert.are.same({ "running", 40 }, events[2])
+    assert.are.same({ "success" }, events[count])
+    assert.are.equal(count, #events)
+  end)
+
+  it("stops resending a progress that has not been updated for too long", function()
+    ui.progress_timing = { keepalive_ms = 10, stall_ms = 0 }
+    local progress = ui.progress("Test")
+
+    progress:report("Working", "running")
+    vim.wait(50)
+
+    assert.are.same({ { "running" } }, events)
+    progress:report("Done", "success")
+  end)
+end)