chore(emacs): Move emacs config to tools/emacs

1 files changed, 266 insertions, 0 deletions

diff --git a/tools/emacs/init/functions.el b/tools/emacs/init/functions.el
new file mode 100644
index 000000000000..8b96a0e737df
--- /dev/null
+++ b/tools/emacs/init/functions.el
@@ -0,0 +1,266 @@
+(require 's)
+;; A few handy functions I use in init.el (or not, but they're nice to
+;; have)
+
+(defun custom-download-theme (url filename)
+  "Downloads a theme through HTTP and places it in ~/.emacs.d/themes"
+
+  ;; Ensure the directory exists
+  (unless (file-exists-p "~/.emacs.d/themes")
+    (make-directory "~/.emacs.d/themes"))
+
+  ;; Adds the themes folder to the theme load path (if not already
+  ;; there)
+  (unless (member "~/.emacs.d/themes" custom-theme-load-path)
+    (add-to-list 'custom-theme-load-path "~/.emacs.d/themes"))
+
+  ;; Download file if it doesn't exist.
+
+  (let ((file
+         (concat "~/.emacs.d/themes/" filename)))
+    (unless (file-exists-p file)
+      (url-copy-file url file))))
+
+(defun custom-download-script (url filename)
+  "Downloads an Elisp script, places it in ~/.emacs/other and then loads it"
+
+  ;; Ensure the directory exists
+  (unless (file-exists-p "~/.emacs.d/other")
+    (make-directory "~/.emacs.d/other"))
+
+  ;; Download file if it doesn't exist.
+  (let ((file
+         (concat "~/.emacs.d/other/" filename)))
+    (unless (file-exists-p file)
+      (url-copy-file url file))
+
+    (load file)))
+
+(defun keychain-password (account &optional keychain)
+  "Returns the password for the account, by default it's looked up in the Login.keychain but a
+   different keychain can be specified."
+  (let ((k (if keychain keychain "Login.keychain")))
+    (replace-regexp-in-string
+     "\n" ""
+     (shell-command-to-string (concat  "security find-generic-password -w -a "
+                                       account
+                                       " "
+                                       k)))))
+
+;; This clones a git repository to 'foldername in .emacs.d
+;; if there isn't already a folder with that name
+(defun custom-clone-git (url foldername)
+  "Clones a git repository to .emacs.d/foldername"
+  (let ((fullpath (concat "~/.emacs.d/" foldername)))
+    (unless (file-exists-p fullpath)
+      (async-shell-command (concat "git clone " url " " fullpath)))))
+
+(defun load-file-if-exists (filename)
+  (if (file-exists-p filename)
+      (load filename)))
+
+(defun goto-line-with-feedback ()
+  "Show line numbers temporarily, while prompting for the line number input"
+  (interactive)
+  (unwind-protect
+      (progn
+        (setq-local display-line-numbers t)
+        (let ((target (read-number "Goto line: ")))
+          (avy-push-mark)
+          (goto-line target)))
+    (setq-local display-line-numbers nil)))
+
+
+(defun untabify-buffer ()
+  (interactive)
+  (untabify (point-min) (point-max)))
+
+(defun indent-buffer ()
+  (interactive)
+  (indent-region (point-min) (point-max)))
+
+(defun cleanup-buffer ()
+  "Perform a bunch of operations on the whitespace content of a buffer.
+Including indent-buffer, which should not be called automatically on save."
+  (interactive)
+  (untabify-buffer)
+  (delete-trailing-whitespace)
+  (indent-buffer))
+
+;; These come from the emacs starter kit
+
+(defun esk-add-watchwords ()
+  (font-lock-add-keywords
+   nil '(("\\<\\(FIX\\(ME\\)?\\|TODO\\|DEBUG\\|HACK\\|REFACTOR\\|NOCOMMIT\\)"
+          1 font-lock-warning-face t))))
+
+(defun esk-sudo-edit (&optional arg)
+  (interactive "p")
+  (if (or arg (not buffer-file-name))
+      (find-file (concat "/sudo:root@localhost:" (read-file-name "File: ")))
+    (find-alternate-file (concat "/sudo:root@localhost:" buffer-file-name))))
+
+;; Open Fefes blog
+(defun fefes-blog ()
+  (interactive)
+  (eww "https://blog.fefe.de/"))
+
+;; Open this machines NixOS config
+(defun nix-config ()
+  (interactive)
+  (find-file "/etc/nixos/configuration.nix"))
+
+;; Open the NixOS man page
+(defun nixos-man ()
+  (interactive)
+  (man "configuration.nix"))
+
+;; Open local emacs configuration
+(defun emacs-config ()
+  (interactive)
+  (dired "~/.emacs.d/"))
+
+;; Get the nix store path for a given derivation.
+;; If the derivation has not been built before, this will trigger a build.
+(defun nix-store-path (derivation)
+  (let ((expr (concat "with import <nixos> {}; " derivation)))
+    (s-chomp (shell-command-to-string (concat "nix-build -E '" expr "'")))))
+
+(defun insert-nix-store-path ()
+  (interactive)
+  (let ((derivation (read-string "Derivation name (in <nixos>): ")))
+    (insert (nix-store-path derivation))))
+
+(defun toggle-force-newline ()
+  "Buffer-local toggle for enforcing final newline on save."
+  (interactive)
+  (setq-local require-final-newline (not require-final-newline))
+  (message "require-final-newline in buffer %s is now %s"
+           (buffer-name)
+           require-final-newline))
+
+;; Helm includes a command to run external applications, which does
+;; not seem to exist in ivy. This implementation uses some of the
+;; logic from Helm to provide similar functionality using ivy.
+(defun list-external-commands ()
+  "Creates a list of all external commands available on $PATH
+  while filtering NixOS wrappers."
+  (cl-loop
+   for dir in (split-string (getenv "PATH") path-separator)
+   when (and (file-exists-p dir) (file-accessible-directory-p dir))
+   for lsdir = (cl-loop for i in (directory-files dir t)
+                        for bn = (file-name-nondirectory i)
+                        when (and (not (s-contains? "-wrapped" i))
+                                  (not (member bn completions))
+                                  (not (file-directory-p i))
+                                  (file-executable-p i))
+                        collect bn)
+   append lsdir into completions
+   finally return (sort completions 'string-lessp)))
+
+(defun run-external-command (cmd)
+    "Execute the specified command and notify the user when it
+  finishes."
+    (message "Starting %s..." cmd)
+    (set-process-sentinel
+     (start-process-shell-command cmd nil cmd)
+     (lambda (process event)
+       (when (string= event "finished\n")
+         (message "%s process finished." process)))))
+
+(defun ivy-run-external-command ()
+  "Prompts the user with a list of all installed applications and
+  lets them select one to launch."
+
+  (interactive)
+  (let ((external-commands-list (list-external-commands)))
+    (ivy-read "Command:" external-commands-list
+              :require-match t
+              :history 'external-commands-history
+              :action #'run-external-command)))
+
+(defun ivy-password-store (&optional password-store-dir)
+  "Custom version of password-store integration with ivy that
+  actually uses the GPG agent correctly."
+
+  (interactive)
+  (ivy-read "Copy password of entry: "
+            (password-store-list (or password-store-dir (password-store-dir)))
+            :require-match t
+            :keymap ivy-pass-map
+            :action (lambda (entry)
+                      (let ((password (auth-source-pass-get 'secret entry)))
+                        (password-store-clear)
+                        (kill-new password)
+                        (setq password-store-kill-ring-pointer kill-ring-yank-pointer)
+                        (message "Copied %s to the kill ring. Will clear in %s seconds."
+                                 entry (password-store-timeout))
+                        (setq password-store-timeout-timer
+                              (run-at-time (password-store-timeout)
+                                           nil 'password-store-clear))))))
+
+(defun ivy-browse-repositories ()
+  "Select a git repository and open its associated magit buffer."
+
+  (interactive)
+  (ivy-read "Repository: "
+            (magit-list-repos)
+            :require-match t
+            :sort t
+            :action #'magit-status))
+
+(defun warmup-gpg-agent (arg &optional exit)
+  "Function used to warm up the GPG agent before use. This is
+   useful in cases where there is no easy way to make pinentry run
+   in the correct context (such as when sending email)."
+  (interactive)
+  (message "Warming up GPG agent")
+  (epg-sign-string (epg-make-context) "dummy")
+  nil)
+
+(defun bottom-right-window-p ()
+  "Determines whether the last (i.e. bottom-right) window of the
+  active frame is showing the buffer in which this function is
+  executed."
+  (let* ((frame (selected-frame))
+         (right-windows (window-at-side-list frame 'right))
+         (bottom-windows (window-at-side-list frame 'bottom))
+         (last-window (car (seq-intersection right-windows bottom-windows))))
+    (eq (current-buffer) (window-buffer last-window))))
+
+(defun inferior-erlang-nix-shell ()
+  "Start an inferior Erlang process from the root of the current
+  project."
+  (interactive)
+  (inferior-erlang
+   (format "nix-shell --command erl %s" (cdr (project-current)))))
+
+(defun intero-fix-ghci-panic ()
+  "Disable deferring of out of scope variable errors, which
+  triggers a bug in the interactive Emacs REPL printing a panic
+  under certain conditions."
+
+  (interactive)
+  (let* ((root (intero-project-root))
+         (package-name (intero-package-name))
+         (backend-buffer (intero-buffer 'backend))
+         (name (format "*intero:%s:%s:repl*"
+                       (file-name-nondirectory root)
+                       package-name))
+         (setting ":set -fno-defer-out-of-scope-variables\n"))
+    (when (get-buffer name)
+      (with-current-buffer (get-buffer name)
+        (goto-char (point-max))
+        (let ((process (get-buffer-process (current-buffer))))
+          (when process (process-send-string process setting)))))))
+
+;; Brute-force fix: Ensure the setting is injected every time the REPL
+;; is selected.
+;;
+;; Upstream issue: https://github.com/commercialhaskell/intero/issues/569
+(advice-add 'intero-repl :after (lambda (&rest r) (intero-fix-ghci-panic))
+            '((name . intero-panic-fix)))
+(advice-add 'intero-repl-load :after (lambda (&rest r) (intero-fix-ghci-panic))
+            '((name . intero-panic-fix)))
+
+(provide 'functions)