emacs/lisp/+setup.el

;;; +setup.el -- my `setup' commands -*- lexical-binding: t -*-

;; Author: Case Duckworth <acdw@acdw.net>

;; This file is NOT part of GNU Emacs.

;;; License:
;; Everyone is permitted to do whatever with this software, without
;; limitation.  This software comes without any warranty whatsoever,
;; but with two pieces of advice:
;; - Don't hurt yourself.
;; - Make good choices.

;;; Commentary:

;; `setup', by Philip Kaludercic, is a wonderful package that works
;; sort of like `use-package', but to my mind it's cleaner and easier
;; to extend.  These are my additions to the local macros provided by
;; the package.

;;; Code:

(require 'el-patch)
(require 'setup)
(require 'straight)
(require 'cl-lib)

(defun +setup-warn (message &rest args)
  "Warn the user that something bad happened in `setup'."
  (display-warning 'setup (format message args)))

(defun +setup-wrap-to-demote-errors (body name)
  "Wrap BODY in a `with-demoted-errors' block.
This behavior is prevented if `setup-attributes' contains the
symbol `without-error-demotion'.

This function differs from `setup-wrap-to-demote-errors' in that
it includes the NAME of the setup form in the warning output."
  (if (memq 'without-error-demotion setup-attributes)
      body
    `(with-demoted-errors ,(format "Error in setup form on line %d (%s): %%S"
                                   (line-number-at-pos)
                                   name)
       ,body)))


;;; New forms

(setup-define :quit
  'setup-quit
  :documentation "Quit the current `setup' form.
Good for commenting.")

(setup-define :face
  (lambda (face spec)
    `(custom-set-faces (list ,face ,spec 'now "Customized by `setup'.")))
  :documentation "Customize FACE with SPEC using `custom-set-faces'."
  :repeatable t)

(setup-define :load-after
  (lambda (&rest features)
    (let ((body `(require ',(setup-get 'feature))))
      (dolist (feature (nreverse features))
        (setq body `(with-eval-after-load ',feature ,body)))
      body))
  :documentation "Load the current feature after FEATURES.")

(setup-define :load-from
  (lambda (path)
    `(let ((path* (expand-file-name ,path)))
       (if (file-exists-p path*)
           (add-to-list 'load-path path*)
         ,(setup-quit))))
  :documentation "Add PATH to load path.
This macro can be used as NAME, and it will replace itself with
the nondirectory part of PATH.
If PATH does not exist, abort the evaluation."
  :shorthand (lambda (args)
               (intern
                (file-name-nondirectory
                 (directory-file-name (cadr args))))))

(setup-define :needs
  (lambda (executable)
    `(unless (executable-find ,executable)
       ,(setup-quit)))
  :documentation "If EXECUTABLE is not in the path, stop here."
  :repeatable 1)


;;; Package integrations

;;; Straight.el

(defun setup--straight-handle-arg (arg var)
  (cond
   ((and (boundp var) (symbol-value var)) t)
   ((keywordp arg) (set var t))
   ((functionp arg) (set var nil) (funcall arg))
   ((listp arg) (set var nil) arg)))

(with-eval-after-load 'straight
  (setup-define :straight
    (lambda (recipe &rest predicates)
      (let* ((skp (make-symbol "straight-keyword-p"))
             (straight-use-p
              (cl-mapcar
                 (lambda (f) (setup--straight-handle-arg f skp))
                 predicates))
             (form `(unless (and ,@straight-use-p
                                 (condition-case e
                                     (straight-use-package ',recipe)
                                   (error
                                    (+setup-warn ":straight error: %S"
                                                 ',recipe)
                                    ,(setup-quit))
                                   (:success t)))
                      ,(setup-quit))))
        ;; Keyword arguments --- :quit is special and should short-circuit
        (if (memq :quit predicates)
            (setq form `,(setup-quit))
          ;; Otherwise, handle the rest of them ...
          (when-let ((after (cadr (memq :after predicates))))
            (setq form `(with-eval-after-load ,(if (eq after t)
                                                   (setup-get 'feature)
                                                 after)
                          ,form))))
        ;; Finally ...
        form))
    :documentation "Install RECIPE with `straight-use-package'.
If PREDICATES are given, only install RECIPE if all of them return non-nil.
The following keyword arguments are also recognized:
- :quit          --- immediately stop evaluating.  Good for commenting.
- :after FEATURE --- only install RECIPE after FEATURE is loaded.
                     If FEATURE is t, install RECIPE after the current feature."
    :repeatable nil
    :indent 1
    :shorthand (lambda (sexp)
                 (let ((recipe (cadr sexp)))
                   (or (car-safe recipe) recipe)))))

;;; Apheleia

(setup-define :apheleia
  (lambda (name formatter &optional mode -pend)
    (let* ((mode (or mode (setup-get 'mode)))
           (current-formatters (and -pend
                                    (alist-get mode apheleia-formatters))))
      `(with-eval-after-load 'apheleia
         (setf (alist-get ',name apheleia-formatters)
               ,formatter)
         (setf (alist-get ',mode apheleia-mode-alist)
               ',(pcase -pend
                   (:append (append (ensure-list current-formatters)
                                    (list name)))
                   (:prepend (cons name (ensure-list current-formatters)))
                   ('nil name)
                   (_ (error "Improper `:apheleia' -PEND argument")))))))
  :documentation
  "Register a formatter to `apheleia''s lists.
NAME is the name given to the formatter in `apheleia-formatters'
and `apheleia-mode-alist'.  FORMATTER is the command paired with
NAME in `apheleia-formatters'.  MODE is the mode or modes to add
NAME to in `apheleia-mode-alist'.  If MODE is not given or nil,
use the setup form's MODE.  Optional argument -PEND can be one of
`:append' or `:prepend', and if given will append or prepend the
given NAME to the current formatters for the MODE in
`apheleia-mode-alist', rather than replace them (the default).

Example:
(setup
 (:apheleia isort (\"isort\" \"--stdout\" \"-\")
                  python-mode))
; =>
(progn
  (setf (alist-get 'isort apheleia-formatters)
        '(\"isort\" \"--stdout\" \"-\"))
  (setf (alist-get 'python-mode apheleia-mode-alist)
        'isort))

This form cannot be repeated, and it cannot be used as HEAD.")


;;; Redefines of `setup' forms

(setup-define :bind-into
  (lambda (feature-or-map &rest rest)
    (cl-loop for f/m in (ensure-list feature-or-map)
             collect (if (string-match-p "-map\\'" (symbol-name f/m))
                         `(:with-map ,f/m (:bind ,@rest))
                       `(:with-feature ,f/m (:bind ,@rest)))
             into forms
             finally return `(progn ,@forms)))
  :documentation "Bind into keys into the map(s) of FEATURE-OR-MAP.
FEATURE-OR-MAP can be a feature or map name or a list of them.
The arguments REST are handled as by `:bind'."
  :debug '(sexp &rest form sexp)
  :indent 1)

(setup-define :require
  (lambda (&rest features)
    (require 'cl-lib)
    (if features
        `(progn ,@(cl-loop for feature in features collect
                           `(unless (require ',feature nil t)
                              ,(setup-quit))))
      `(unless (require ',(setup-get 'feature) nil t)
         ,(setup-quit))))
  :documentation "Try to require FEATURE, or stop evaluating body.
This macro can be used as NAME, and it will replace itself with
the first FEATURE."
  :repeatable nil
  :shorthand #'cadr)

(provide '+setup)
;;; +setup.el ends here