lsp-dart

Emacs Dart IDE using lsp-mode to connect to Dart Analysis Server.

LSP works great with Flutter, but there are also other packages that may help to improve your development, for more info see Additional packages.

Quickstart

The following has a example to setup lsp-dart.

;; Install use-package
(condition-case nil
    (require 'use-package)
  (file-error
   (require 'package)
   (add-to-list 'package-archives '("melpa" . "http://melpa.org/packages/"))
   (package-initialize)
   (package-refresh-contents)
   (package-install 'use-package)
   (require 'use-package)))

(use-package lsp-mode :ensure t)
(use-package lsp-dart 
  :ensure t 
  :hook (dart-mode . lsp))

;; Optional packages
(use-package projectile :ensure t) ;; project management
(use-package yasnippet
  :ensure t
  :config (yas-global-mode)) ;; snipets
(use-package lsp-ui :ensure t) ;; UI for LSP
(use-package company :ensure t) ;; Auto-complete

;; Optional Flutter packages
(use-package hover :ensure t) ;; run app from desktop without emulator

Features

Besides the lsp-mode features, lsp-dart implements the custom methods features from the dart_analysis_server.

Closing labels

Tree views

lsp-dart uses lsp-treemacs for rendering some tree views features.

lsp-dart-show-outline ⚠️*

lsp-dart-show-flutter-outline ⚠️*

Run/Debug tests

lsp-dart-run-all-tests - Run all tests from project.

lsp-dart-run-test-file - Run all tests from current test buffer.

lsp-dart-run-test-at-point - Run single test at point.

lsp-dart-debug-test-at-point - Debug single test at point.

lsp-dart-visit-last-test - Go to last ran test.

lsp-dart-run-last-test - Run last ran test.

lsp-dart-debug-last-test - Debug last ran test.

Running a test interactively:

Flutter colors

Display the flutter colors on left fringe.

You can disable the feature setting lsp-dart-flutter-fringe-colors to nil.

Flutter widget guides

Display widget guide lines from parent to child widgets on flutter. ⚠️*

You can disable the feature setting lsp-dart-flutter-widget-guides to nil.

Debug

For debugging, lsp-dart uses dap-mode. You only need to run dap-dart-setup one time to setup the debugger to your Emacs and dap-debug to start the debug.

⚠️ It requires npm and node on exec-path to install/use the debugger feature.

Flutter

lsp-dart support Flutter debugging too via dap-debug with an option to select the device to debug.

After the debug session has started, you can run:

lsp-dart-flutter-hot-restart - Trigger Flutter hot restart on the debug sessions. lsp-dart-flutter-hot-reload - Trigger Flutter hot reload on the debug sessions.

Custom templates

You can register a custom template for debugging with dap-register-debug-template, check the following example:

(use-package lsp-dart
  :ensure t
  :hook (dart-mode . lsp)
  :init
  (dap-register-debug-template "Flutter :: Custom debug"
                               (list :flutterPlatform "x86_64"
                                     :program "lib/main_debug.dart"
                                     :args '("--flavor" "customer_a"))))

flutterPlatform,:program, and :args are all optional.

A full list of supported parameters can be found in the source of the function lsp-dart-dap--populate-flutter-start-file-args in lsp-dart-dap.el. Several of these parameters can be configured by setting one of the Supported settings with matching names.

DevTools

You can also open the Dart DevTools on the current debug session with lsp-dart-open-devtools.

⚠️* Features only available for Dart SDK version 2.8.0 or above.

Supported settings

Variable	Description	Default
`lsp-dart-sdk-dir`	The optional Dart SDK path. If nil and in a flutter project, it will try to find the dart SDK from Flutter SDK cache dir, otherwise it will search for a dart executable in `$PATH`.	`nil`
`lsp-dart-flutter-sdk-dir`	The optional Flutter SDK path. If nil, it will try to find the Flutter SDK from the `flutter` executable in `$PATH` and if not found, it will try in `$FLUTTER_ROOT`.	`nil`
`lsp-dart-server-command`	`analysis_server` executable to use	Check source file
`lsp-dart-extra-library-directories`	Extra libs to analyze besides Dart SDK libs	`'()`
`lsp-dart-only-analyze-projects-with-open-files`	Analysis will only be performed for projects that have open files rather than the root workspace folder	`t`
`lsp-dart-suggest-from-unimported-libraries`	Completion will not include symbols that are not already imported into the current file.	`t`
`lsp-dart-closing-labels`	Enable the closing labels feature on server lsp	`t`
`lsp-dart-closing-labels-prefix`	The prefix string to be concatenated with the closing label	`""`
`lsp-dart-closing-labels-size`	The font size factor to be multiplied by the closing labels font size	0.9
`lsp-dart-outline`	Enable the outline tree view feature on server lsp	`t`
`lsp-dart-outline-position-params`	The outline tree position params.	Left side
`lsp-dart-flutter-outline`	Wheter to enable the Flutter outline tree view feature on server lsp	`t`
`lsp-dart-flutter-outline-position-params`	The Flutter outline tree position params	Left side
`lsp-dart-flutter-fringe-colors`	Enable the Flutter colors on fringe.	`t`
`lsp-dart-flutter-widget-guides`	Enable the Flutter widget guide lines from parent to child widgets	`t`
`lsp-dart-main-code-lens`	Enable the `Run	Debug` code lens on main methods.
`lsp-dart-test-code-lens`	Enable the `Run	Debug` code lens on tests.
`lsp-dart-dap-extension-version`	The debugger extension version.	3.10.1
`lsp-dart-dap-debugger-path`	The debugger extension path	Check source file
`lsp-dart-dap-dart-debugger-program`	The command to execute the debugger extension on dart projects.	Check source file
`lsp-dart-dap-dart-test-debugger-program`	The command to execute the test debugger extension on dart projects.	Check source file
`lsp-dart-dap-flutter-debugger-program`	The command to execute the debugger extension on flutter projects.	Check source file
`lsp-dart-dap-flutter-test-debugger-program`	The command to execute the test debugger extension on flutter projects.	Check source file
`lsp-dart-dap-debug-external-libraries`	Whether to enable the debug on external libraries	`nil`
`lsp-dart-dap-debug-sdk-libraries`	Whether to enable the debug on Dart SDK libraries	`nil`
`lsp-dart-dap-vm-additional-args`	Additional args for dart debugging VM when the debugging.	`""`
`lsp-dart-dap-flutter-track-widget-creation`	Whether to pass –track-widget-creation to Flutter apps. Required to support 'Inspect Widget'.	`t`
`lsp-dart-dap-flutter-structured-errors`	Whether to use Flutter’s structured error support for improve error display.	`t`
`lsp-dart-dap-flutter-verbose-log`	Whether to enable verbose logs from Flutter DAP	`nil`
`lsp-dart-devtools-theme`	The devtools theme when openning via `lsp-dart-dap-open-devtools`	`"dark"`
`lsp-dart-devtools-hide-options`	What to hide when openning DevTools via `lsp-dart-dap-open-devtools`	`debugger`

Additional packages

lsp-ui : Flycheck, documentation and code actions support.
lsp-treemacs : lsp-mode GUI controls implemented using treemacs.
company-capf : Completion backend support.
flutter.el : Tool to run emulator from emacs.
hover.el : Tool to run flutter mobile apps from desktop without the need of an emulator.

FAQ

❔ Emacs can't find my package, it keeps searching up until the dart root package folder.

🔹 Configure projectile to find the package pubspec.yaml and set the folder as project root:

(with-eval-after-load 'projectile
  (add-to-list 'projectile-project-root-files-bottom-up "pubspec.yaml")
  (add-to-list 'projectile-project-root-files-bottom-up "BUILD"))

❔ LSP :: No LSP server for dart-mode(check *lsp-log*).

🔹 Try to set the lsp-dart-sdk-dir to the Dart SDK dir instalation or if you are using Flutter, <your-flutter-dir>/bin/cache/dart-sdk/.

Community

All feedback and suggestions are very welcome!

You can open a issue or for a quick anwser, send a message on Gitter.

n3wtn9 / lsp-dart