feat: add FlutterAttach command (#425)

Author: sidlatau

README.md

@@ -155,6 +155,7 @@ require("flutter-tools").setup {} -- use defaults
 - `FlutterReload` - Reload the running project.
 - `FlutterRestart` - Restart the current project.
 - `FlutterQuit` - Ends a running session.
+- `FlutterAttach` - Attach to a running app.
 - `FlutterDetach` - Ends a running session locally but keeps the process running on the device.
 - `FlutterOutlineToggle` - Toggle the outline window showing the widget tree for the given file.
 - `FlutterOutlineOpen` - Opens an outline window showing the widget tree for the given file.

lua/flutter-tools.lua

@@ -25,6 +25,7 @@ local function setup_commands()
   command("FlutterRun", function(data) commands.run_command(data.args) end, { nargs = "*" })
   command("FlutterDebug", function(data) commands.run_command(data.args) end, { nargs = "*" })
   command("FlutterLspRestart", lsp.restart)
+  command("FlutterAttach", commands.attach)
   command("FlutterDetach", commands.detach)
   command("FlutterReload", commands.reload)
   command("FlutterRestart", commands.restart)

lua/flutter-tools/commands.lua

@@ -16,6 +16,7 @@ local parser = lazy.require("flutter-tools.utils.yaml_parser")
 local M = {}
 
 ---@alias RunOpts {cli_args: string[]?, args: string[]?, device: Device?, force_debug: boolean?}
+---@alias AttachOpts {cli_args: string[]?, args: string[]?, device: Device?}
 
 ---@type table?
 local current_device = nil
@@ -25,6 +26,7 @@ local current_device = nil
 ---@field run fun(runner: flutter.Runner, paths:table, args:table, cwd:string, on_run_data:fun(is_err:boolean, data:string), on_run_exit:fun(data:string[], args: table, project_conf: flutter.ProjectConfig?,launch_config: dap.Configuration?),  is_flutter_project: boolean, project_conf: flutter.ProjectConfig?, launch_config: dap.Configuration?)
 ---@field cleanup fun(funner: flutter.Runner)
 ---@field send fun(runner: flutter.Runner, cmd:string, quiet: boolean?)
+---@field attach fun(runner: flutter.Runner, paths:table, args:table, cwd:string, on_run_data:fun(is_err:boolean, data:string), on_run_exit:fun(data:string[], args: table, project_conf: flutter.ProjectConfig?,launch_config: dap.Configuration?))
 
 ---@type flutter.Runner?
 local runner = nil
@@ -306,6 +308,27 @@ function M.run(opts, project_conf, launch_config)
   end
 end
 
+---@param opts AttachOpts
+local function attach(opts)
+  opts = opts or {}
+  executable.get(function(paths)
+    local args = opts.cli_args or {}
+    if not use_debugger_runner() then vim.list_extend(args, { "attach" }) end
+
+    local cwd = get_cwd()
+    ui.notify("Attaching flutter project...")
+    runner = use_debugger_runner() and debugger_runner or job_runner
+    runner:attach(paths, args, cwd, on_run_data, on_run_exit)
+  end)
+end
+
+--- Attach to a running app
+---@param opts AttachOpts
+function M.attach(opts)
+  if M.is_running() then return ui.notify("Flutter is already running!") end
+  attach(opts)
+end
+
 ---@param cmd string
 ---@param quiet boolean?
 ---@param on_send function|nil

lua/flutter-tools/runners/debugger_runner.lua

@@ -102,35 +102,15 @@ local function register_default_configurations(paths, is_flutter_project, projec
   end
 end
 
-function DebuggerRunner:run(
-  paths,
-  args,
-  cwd,
-  on_run_data,
-  on_run_exit,
-  is_flutter_project,
-  project_config,
-  last_launch_config
-)
-  ---@type dap.Configuration
-  local selected_launch_config = nil
-
+local function register_dap_listeners(on_run_data, on_run_exit)
   local started = false
   local before_start_logs = {}
-  vm_service_extensions.reset()
   dap.listeners.after["event_output"][plugin_identifier] = function(_, body)
-    if body and body.output then
-      for line in body.output:gmatch("[^\r\n]+") do
-        if not started then table.insert(before_start_logs, line) end
-        on_run_data(body.category == "sterr", line)
-      end
-    end
+    on_run_data(started, before_start_logs, body)
   end
 
   local handle_termination = function()
-    if next(before_start_logs) ~= nil then
-      on_run_exit(before_start_logs, args, project_config, selected_launch_config)
-    end
+    if next(before_start_logs) ~= nil then on_run_exit(before_start_logs) end
   end
 
   dap.listeners.before["event_exited"][plugin_identifier] = function(_, _) handle_termination() end
@@ -160,6 +140,35 @@ function DebuggerRunner:run(
       vm_service_extensions.set_service_extensions_state(body.extension, body.value)
     end
   end
+end
+
+function DebuggerRunner:run(
+  paths,
+  args,
+  cwd,
+  on_run_data,
+  on_run_exit,
+  is_flutter_project,
+  project_config,
+  last_launch_config
+)
+  vm_service_extensions.reset()
+  ---@type dap.Configuration
+  local selected_launch_config = nil
+
+  register_dap_listeners(
+    function(started, before_start_logs, body)
+      if body and body.output then
+        for line in body.output:gmatch("[^\r\n]+") do
+          if not started then table.insert(before_start_logs, line) end
+          on_run_data(body.category == "sterr", line)
+        end
+      end
+    end,
+    function(before_start_logs)
+      on_run_exit(before_start_logs, args, project_config, selected_launch_config)
+    end
+  )
 
   register_debug_adapter(paths, is_flutter_project)
   local launch_configurations = {}
@@ -212,6 +221,60 @@ function DebuggerRunner:run(
   end
 end
 
+function DebuggerRunner:attach(paths, args, cwd, on_run_data, on_run_exit)
+  vm_service_extensions.reset()
+  register_dap_listeners(function(started, before_start_logs, body)
+    if body and body.output then
+      for line in body.output:gmatch("[^\r\n]+") do
+        if not started then table.insert(before_start_logs, line) end
+        on_run_data(body.category == "sterr", line)
+      end
+    end
+  end, function(before_start_logs) on_run_exit(before_start_logs, args) end)
+
+  register_debug_adapter(paths, true)
+  local launch_configurations = {}
+  local launch_configuration_count = 0
+  register_default_configurations(paths, true)
+  if config.debugger.register_configurations then config.debugger.register_configurations(paths) end
+  local all_configurations = require("dap").configurations.dart
+  if not all_configurations then
+    ui.notify("No launch configuration for DAP found", ui.ERROR)
+    return
+  end
+  for _, c in ipairs(all_configurations) do
+    if c.request == "attach" then
+      table.insert(launch_configurations, c)
+      launch_configuration_count = launch_configuration_count + 1
+    end
+  end
+
+  if launch_configuration_count == 0 then
+    ui.notify("No launch configuration for DAP found", ui.ERROR)
+    return
+  else
+    require("dap.ui").pick_if_many(
+      launch_configurations,
+      "Select launch configuration",
+      function(item)
+        return fmt("%s : %s | %s", item.name, item.program or item.cwd, vim.inspect(item.args))
+      end,
+      function(launch_config)
+        if not launch_config then return end
+        launch_config = vim.deepcopy(launch_config)
+        if not launch_config.cwd then launch_config.cwd = cwd end
+        launch_config.args = vim.list_extend(launch_config.args or {}, args or {})
+        launch_config.dartSdkPath = paths.dart_sdk
+        launch_config.flutterSdkPath = paths.flutter_sdk
+        if config.debugger.evaluate_to_string_in_debug_views then
+          launch_config.evaluateToStringInDebugViews = true
+        end
+        dap.run(launch_config)
+      end
+    )
+  end
+end
+
 function DebuggerRunner:send(cmd, quiet)
   if cmd == "open_dev_tools" then
     dev_tools.open_dev_tools()

lua/flutter-tools/runners/job_runner.lua

@@ -69,4 +69,23 @@ end
 
 function JobRunner:cleanup() run_job = nil end
 
+function JobRunner:attach(paths, args, cwd, on_run_data, on_run_exit)
+  local command = paths.flutter_bin
+  local command_args = args
+
+  run_job = Job:new({
+    command = command,
+    args = command_args,
+    cwd = cwd,
+    on_start = function() utils.emit_event(utils.events.APP_STARTED) end,
+    on_stdout = vim.schedule_wrap(function(_, data, _)
+      on_run_data(false, data)
+      dev_tools.handle_log(data)
+    end),
+    on_stderr = vim.schedule_wrap(function(_, data, _) on_run_data(true, data) end),
+    on_exit = vim.schedule_wrap(function(j, _) on_run_exit(j:result(), args) end),
+  })
+  run_job:start()
+end
+
 return JobRunner