Dape

#+title: Dape - Debug Adapter Protocol for Emacs #+author: Daniel Pettersson #+property: header-args :results silent #+language: en

#+html: <a href="https://elpa.gnu.org/packages/dape.html"><img alt="GNU ELPA" src="https://elpa.gnu.org/packages/dape.svg"/></a>

=Dape= is a debug adapter client for Emacs. The debug adapter protocol, much like its more well-known counterpart, the language server protocol, aims to establish a common API for programming tools. However, instead of functionalities such as code completions, it provides a standardized interface for debuggers.

To begin a debugging session, invoke the ~dape~ command. In the minibuffer prompt, enter a debug adapter configuration name from ~dape-configs~.

For complete functionality, make sure to enable ~eldoc-mode~ in your source buffers and ~repeat-mode~ for more pleasant key mappings.

• Features

• Batteries included support (~describe-variable~ ~dape-configs~)
• Log breakpoints
• Conditional breakpoints
• Variable explorer
• Variable watch
• Variable hover with ~eldoc~
• REPL
• gdb-mi.el like interface
• Memory editor with ~hexl~
• Disassembly viewer
• Integration with ~compile~
• Debug adapter configuration ergonomics
• No external dependencies outside of core Emacs

With ~(setq dape-buffer-window-arrangement 'right)~: [[https://raw.githubusercontent.com/svaante/dape/resources/right_0_25_0.png]] And with ~(setq dape-buffer-window-arrangement 'gud)~ + =corfu= as ~completion-in-region-function~: [[https://raw.githubusercontent.com/svaante/dape/resources/gud_0_25_0.png]] With "rich" REPL output: [[https://raw.githubusercontent.com/svaante/dape/resources/repl_0_25_0.png]] With =minibuffer= adapter configuration hints: [[https://raw.githubusercontent.com/svaante/dape/resources/minibuffer_0_25_0.png]]

• Configuration =Dape= includes pre-defined debug adapter configurations for various programming languages. Refer to ~dape-configs~ for more details. If =dape= doesn't include a configuration suitable for your needs, you can implement your own.

#+begin_src emacs-lisp (use-package dape :preface ;; By default dape shares the same keybinding prefix as `gud' ;; If you do not want to use any prefix, set it to nil. ;; (setq dape-key-prefix "\C-x\C-a")

:hook
;; Save breakpoints on quit
;; (kill-emacs . dape-breakpoint-save)
;; Load breakpoints on startup
;; (after-init . dape-breakpoint-load)

:custom
;; Turn on global bindings for setting breakpoints with mouse
;; (dape-breakpoint-global-mode +1)

;; Info buffers to the right
;; (dape-buffer-window-arrangement 'right)
;; Info buffers like gud (gdb-mi)
;; (dape-buffer-window-arrangement 'gud)
;; (dape-info-hide-mode-line nil)

;; Projectile users
;; (dape-cwd-function #'projectile-project-root)

:config
;; Pulse source line (performance hit)
;; (add-hook 'dape-display-source-hook #'pulse-momentary-highlight-one-line)

;; Save buffers on startup, useful for interpreted languages
;; (add-hook 'dape-start-hook (lambda () (save-some-buffers t t)))

;; Kill compile buffer on build success
;; (add-hook 'dape-compile-hook #'kill-buffer)
)

;; For a more ergonomic Emacs and `dape' experience (use-package repeat :custom (repeat-mode +1))

;; Left and right side windows occupy full frame height (use-package emacs :custom (window-sides-vertical t)) #+end_src

• Differences with dap-mode Dape has no dependencies outside of core Emacs packages, and tries to use get as much out of them possible.

Dape takes a slightly different approach to configuration.

• =Dape= does not support ~launch.json~ files, if per project configuration is needed use ~dir-locals~ and ~dape-command~.
• =Dape= enhances ergonomics within the minibuffer by allowing users to modify or add PLIST entries to an existing configuration using options. For example ~dape-config :cwd default-directory :program ＂/home/user/b.out＂ compile ＂gcc -g -o b.out main.c＂~.
• No magic, no special variables like =${workspaceFolder}=. Instead, functions and variables are resolved before starting a new session.
• Tries to envision how debug adapter configurations would be implemented in Emacs if vscode never existed.

• Supported debug adapters In theory all debug adapters should be compatible with =Dape=.

** Javascript - vscode-js-*

1. Install =node=
2. Visit https://github.com/microsoft/vscode-js-debug/releases/ and download the asset =js-debug-dap-<version>.tar.gz=
3. Unpack ~mkdir -p ~/.emacs.d/debug-adapters && tar -xvzf js-debug-dap-<version>.tar.gz -C ~/.emacs.d/debug-adapters~

For more information see [[https://github.com/microsoft/vscode-js-debug/blob/main/OPTIONS.md][OPTIONS.md]].

** Go - dlv See [[https://github.com/go-delve/delve/tree/master/Documentation/installation][delve installation]]. For more information see [[https://github.com/go-delve/delve/blob/master/Documentation/usage/dlv_dap.md][documentation]].

** C, C++, Rust, and more - GDB Ensure that your GDB version is 14.1 or newer. For further details, consult the [[https://sourceware.org/gdb/current/onlinedocs/gdb.html/Debugger-Adapter-Protocol.html][documentation]].

** C, C++ and Rust - codelldb

1. Download latest =vsix= [[https://github.com/vadimcn/codelldb/releases][release]] for your platform =codelldb-<platform>-<os>.vsix=
2. Unpack ~mkdir -p ~/.emacs.d/debug-adapters && unzip codelldb-<platform>-<os>.vsix -d ~/.emacs.d/debug-adapters/codelldb~

See [[https://github.com/vadimcn/codelldb/blob/v1.10.0/MANUAL.md][manual]] for more information.

** C and C++ - cpptools Download latesnd unpack =vsix= file with your favorite unzipper.

1. Download latest =vsix= [[https://github.com/microsoft/vscode-cpptools/releases][release]] for your platform =cpptools-<platform>-<os>.vsix=
2. Unpack ~mkdir -p ~/.emacs.d/debug-adapters && unzip cpptools-<os>-<platform>.vsix -d ~/.emacs.d/debug-adapters/cpptools~
3. Then ~chmod +x ~/.emacs.d/debug-adapters/cpptools/extension/debugAdapters/bin/OpenDebugAD7~
4. And ~chmod +x ~/.emacs.d/debug-adapters/cpptools/extension/debugAdapters/lldb-mi/bin/lldb-mi~

See [[https://code.visualstudio.com/docs/cpp/launch-json-reference][options]].

** C, C++ and Rust - lldb-dap

1. Install [[https://github.com/helix-editor/helix/wiki/Debugger-Configurations#install-debuggers][lldb-dap]] for your platform

*** Example for MacOS using homebrew

1. Install the =llvm= keg: =brew install llvm=
2. Prepend the =llvm= path to the =PATH= variable (=$(brew --prefix --installed llvm)/bin=)
3. =M-x dape= and pass in arguments of interest

• To pass arguments, use =:args ["arg1" "arg2" ..]=
• To pass environment variables, use =:env (:RUST_LOG "WARN" :FOO "BAR")=
• To use a different program instead of =a.out= (e.g., for Rust), use =:program "target/debug/<crate_name>"=

** Python - debugpy Install debugpy with pip ~pip install debugpy~

See [[https://github.com/microsoft/debugpy/wiki/Debug-configuration-settings][options]].

** Godot Configure debug adapter port under "Editor" > "Editor Settings" > "Debug Adapter".

** Dart - flutter See for installation https://docs.flutter.dev/get-started/install

** C# - netcoredbg See https://github.com/Samsung/netcoredbg for installation

** Ruby - rdbg Install with ~gem install debug~.

See https://github.com/ruby/debug for more information

** Java - JDTLS with Java Debug Server plugin See https://github.com/eclipse-jdtls/eclipse.jdt.ls for installation of JDTLS. See https://github.com/microsoft/java-debug for installation of the Java Debug Server plugin. The Java config depends on Eglot running JDTLS with the plugin prior to starting Dape. Either globally extend ~eglot-server-programs~ as follows to have JDTLS always load the plugin: #+begin_src emacs-lisp (add-to-list 'eglot-server-programs '((java-mode java-ts-mode) . ("jdtls" :initializationOptions (:bundles ["/PATH/TO/java-debug/com.microsoft.java.debug.plugin/target/com.microsoft.java.debug.plugin-VERSION.jar"])))) #+end_src

Alternatively, set the variable ~eglot-workspace-configuration~ in the file =.dir-locals.el= in a project's root directory, to have JDTLS load the plugin for that project: #+begin_src emacs-lisp ;; content of /project/.dir-locals.el ((nil . ((eglot-workspace-configuration . (:jdtls (:initializationOptions (:bundles ["/PATH/TO/java-debug/com.microsoft.java.debug.plugin/target/com.microsoft.java.debug.plugin-VERSION.jar"]))))))) #+end_src

** PHP - Xdebug

1. Install and setup =Xdebug= see [[https://github.com/xdebug/vscode-php-debug][instructions]]
2. Install =node=
3. Download latest =vsix= [[https://github.com/xdebug/vscode-php-debug/releases][release]] of DAP adapter for =Xdebug= =php-debug-<version>.vsix=
4. Unpack ~mkdir -p ~/.emacs.d/debug-adapters && unzip php-debug-<version>.vsix -d ~/.emacs.d/debug-adapters/php-debug~

** OCaml - ocamlearlybird Install with ~opam install earlybird~.

1. Point =:program= to bytecode file
2. Place breakpoints inside of =_build/default/*=

See [[https://github.com/hackwaly/ocamlearlybird][ocamlearlybird]] for more information.

** Bash - bash-debug

1. Install =node=
2. Download latest =vsix= [[https://github.com/rogalmic/vscode-bash-debug/releases][release]] of DAP adapter =bash-debug-<version>.vsix=
3. Unpack ~mkdir -p ~/.emacs.d/debug-adapters && unzip bash-debug-<version>.vsix -d ~/.emacs.d/debug-adapters/bash-debug~

See [[https://github.com/rogalmic/vscode-bash-debug][bash-debug]] for more information.

** Other untested adapters If you find a working configuration for any other debug adapter please submit a PR.

See [[https://microsoft.github.io/debug-adapter-protocol/implementors/adapters/][microsofts list]] for other adapters, your mileage will vary.

• Contribute =dape= is subject to the same copyright assignment policy as GNU Emacs.

Any legally [[https://www.gnu.org/prep/maintain/html_node/Legall