dotfiles/modules/development.org

#+TITLE: Development
#+AUTHOR: Christopher James Hayward
#+EMAIL: chris@chrishayward.xyz

#+PROPERTY: header-args:emacs-lisp :tangle development.el :comments org
#+PROPERTY: header-args:shell      :tangle no
#+PROPERTY: header-args            :results silent :eval no-export :comments org

#+OPTIONS: num:nil toc:nil todo:nil tasks:nil tags:nil
#+OPTIONS: skip:nil author:nil email:nil creator:nil timestamp:nil

Support for individual programming languages, has a hard dependency on the [[file:projects.org][Projects]] module for integration with *LSP*[fn:1] / *DAP*[fn:2]

* Go

First class language support for *Golang*[fn:3].

+ Full support of *LSP*[fn:1] 
+ Full support of *DAP*[fn:1]

** Installing requirements

Get started by installing the *gopls*[fn:4] language server.

#+begin_src shell
GO111MODULE=on go get golang.org/x/tools/gopls@latest
#+end_src

** Setup the environment

Make some modifications to the environment.

*** Overriding the $GOPATH

Set the =$GOPATH= environment variable prior to loading the module, allowing modification of the default value.

#+begin_src emacs-lisp
(setenv "GOPATH" (concat (getenv "HOME") "/.go/"))
#+end_src

*** Adding $GOBIN to the $PATH

Include the ~bin~ subdirectory of the =$GOPATH= in the =$PATH= variable, adding compiled Golang applications to the system path.

#+begin_src emacs-lisp
(setenv "PATH" (concat (getenv "GOPATH") "bin:" (getenv "PATH")))
#+end_src

** Configuration 

Include the *go-mode*[fn:5] package for integration with *lsp-mode* from the [[file:projects.org][Projects]] module.

#+begin_src emacs-lisp
(use-package go-mode
  :hook (go-mode . lsp)
  :custom (lsp-go-gopls-server-path "~/.go/bin/gopls"))
#+end_src

*** Before save hooks

Apply some custom behaviour prior to saving buffers.

+ Format buffers
+ Organize imports

#+begin_src emacs-lisp
(defun dotfiles/go-hook ()
  (add-hook 'before-save-hook #'lsp-format-buffer t t)
  (add-hook 'before-save-hook #'lsp-organize-imports t t))

(add-hook 'go-mode-hook #'dotfiles/go-hook)
#+end_src

*** Babel structure templates

Add a structure template for *Golang*[fn:3] source blocks.

#+begin_src emacs-lisp
(add-to-list 'org-structure-template-alist '("go" . "src go"))
#+end_src

* HTTP

Interactive with *HTTP* endpoints using the *ob-http*[fn:6] package. You can see how it works in my post [[file:../docs/posts/kanye-as-a-service.org.gpg][Kanye as a Service]]. Essentialy it adds interactive *HTTP* blocks that can output their results in place.

#+begin_src emacs-lisp
(use-package ob-http
  :after org
  :config (org-babel-do-load-languages
            'org-babel-load-languages '((http . t))))
#+end_src

* C/C++

Add support for the *C/C++* family of languages via the *CCLS*[fn:7] language server.

+ Integrate with *LSP*[fn:2]
+ Integrate with *DAP*[fn:1]
+ Load babel language modules
+ Create new structure templates
  * ~<cc~ for *C*
  * ~<cpp~ for *C++*

#+begin_src emacs-lisp
(use-package ccls
  :hook ((c-mode c++-mode objc-mode cuda-mode) .
         (lambda ()
           (require 'ccls)
           (lsp-deferred)))
  :config (add-to-list 'org-structure-template-alist '("cc" . "src C"))
          (add-to-list 'org-structure-template-alist '("cpp" . "src C++"))
          (org-babel-do-load-languages 'org-babel-load-languages '((C . t))))
#+end_src

** Installing requirements

Some required packages, here's how to install on *Debian/Ubuntu*:

#+begin_src shell
sudo apt install ccls
#+end_src

* Python

Adds support for *Python* and *Python 3*[fn:8] with *DAP*[fn:1] and *LSP*[fn:2] integration. The built in Emacs mode *python-mode*[fn:9] implements the behaviour.

+ Load the babel language modules for Python
+ Add a structure template with ~<py~

#+begin_src emacs-lisp
(use-package python-mode
  :hook (python-mode . lsp-deferred)
  :config (require 'dap-python)
          (add-to-list 'org-src-lang-modes '("python" . python))
          (add-to-list 'org-structure-template-alist '("py" . "src python"))
          (org-babel-do-load-languages 'org-babel-load-languages '((python . t)))
  :custom (python-shell-interpreter "python3") ;; Required if "python" is not python 3.
          (dap-python-executable "python3")    ;; Same as above.
          (dap-python-debugger 'debugpy))
#+end_src

** Installing the language server

Install the *pyls*[fn:10] language server.

#+begin_src shell
pip3 install --user "python-language-server[all]"
#+end_src

* PlantUML

Download and install *PlantUML*[fn:11], a text-based markup language for creating UML diagrams. You can read my notes about the tool [[file:../docs/notes/plantuml.org.gpg][PlantUML]] here. Support added through the *plantuml-mode*[fn:12] package.

+ Load the babel module for *PlantUML*[fn:11]
+ Create a structure template with ~<pl~

#+begin_src emacs-lisp
(use-package plantuml-mode
  :after org
  :custom (plantuml-default-exec-mode 'jar)
          (plantuml-jar-path "~/.local/bin/plantuml.jar")
          (org-plantuml-jar-path (expand-file-name "~/.local/bin/plantuml.jar"))
          (org-startup-with-inline-images t)
  :config (add-to-list 'org-src-lang-modes '("plantuml" . plantuml))
          (add-to-list 'org-structure-template-alist '("pl" . "src plantuml"))
          (org-babel-do-load-languages 'org-babel-load-languages '((plantuml . t))))
#+end_src

** View inside of buffers

Toggle inline images with =SPC t i=.

#+begin_src emacs-lisp
(dotfiles/leader
  "ti" '(org-toggle-inline-images :which-key "Images"))
#+end_src

* Resources

[fn:1] https://microsoft.github.io/debug-adapter-protocol
[fn:2] https://microsoft.github.io/language-server-protocol
[fn:3] https://golang.org
[fn:4] https://pkg.go.dev/golang.org/x/tools/gopls
[fn:5] https://emacswiki.org/emacs/GoMode
[fn:6] https://github.com/zweifisch/ob-http
[fn:7] https://github.com/MaskRay/ccls
[fn:8] https://python.org
[fn:9] https://emacswiki.org/emacs/PythonProgrammingInEmacs
[fn:10] https://pypi.org/project/python-language-server/
[fn:11] https://plantuml.com
[fn:12] https://github.com/skuro/plantuml-mode