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Diffstat (limited to 'elpa/skewer-mode-20200304.1142/skewer-html.el')
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1 files changed, 165 insertions, 0 deletions
diff --git a/elpa/skewer-mode-20200304.1142/skewer-html.el b/elpa/skewer-mode-20200304.1142/skewer-html.el new file mode 100644 index 0000000..b21de16 --- /dev/null +++ b/elpa/skewer-mode-20200304.1142/skewer-html.el @@ -0,0 +1,165 @@ +;;; skewer-html.el --- skewer support for live-interaction HTML -*- lexical-binding: t; -*- + +;; This is free and unencumbered software released into the public domain. + +;;; Commentary: + +;; This minor mode provides functionality for HTML like plain Skewer +;; does for JavaScript. There's no clean way to replace the body and +;; head elements of a live document, so "evaluating" these elements is +;; not supported. + +;; * C-M-x -- `skewer-html-eval-tag' + +;; See also `skewer-html-fetch-selector-into-buffer' for grabbing the +;; page as it current exists. + +;;; Code: + +(require 'cl-lib) +(require 'sgml-mode) +(require 'skewer-mode) + +;; Macros + +(defmacro skewer-html--with-html-mode (&rest body) + "Evaluate BODY as if in `html-mode', using a temp buffer if necessary." + (declare (indent 0)) + (let ((orig-buffer (make-symbol "orig-buffer")) + (temp-buffer (make-symbol "temp-buffer")) + (orig-point (make-symbol "orig-point"))) + `(let ((,temp-buffer (and (not (eq major-mode 'html-mode)) + (generate-new-buffer " *skewer-html*"))) + (,orig-buffer (current-buffer)) + (,orig-point (point))) + (unwind-protect + (with-current-buffer (or ,temp-buffer ,orig-buffer) + (when ,temp-buffer + (insert-buffer-substring ,orig-buffer) + (setf (point) ,orig-point) + (html-mode)) + ,@body) + (when ,temp-buffer + (kill-buffer ,temp-buffer)))))) + +;; Selector computation + +(defun skewer-html--cleanup (tag) + "Cleanup TAG name from sgml-mode." + (skewer-html--with-html-mode + (replace-regexp-in-string "/$" "" (sgml-tag-name tag)))) + +(defun skewer-html--tag-after-point () + "Return the tag struct for the tag immediately following point." + (skewer-html--with-html-mode + (save-excursion + (forward-char 1) + (sgml-parse-tag-backward)))) + +(defun skewer-html--get-context () + "Like `sgml-get-context' but to the root, skipping close tags." + (skewer-html--with-html-mode + (save-excursion + (cl-loop for context = (sgml-get-context) + while context + nconc (nreverse context) into tags + finally return (cl-delete 'close tags :key #'sgml-tag-type))))) + +(cl-defun skewer-html-compute-tag-nth (&optional (point (point))) + "Compute the position of this tag within its parent." + (skewer-html--with-html-mode + (save-excursion + (setf (point) point) + (let ((context (skewer-html--get-context))) + (when context + (let ((tag-name (skewer-html--cleanup (car context))) + (target-depth (1- (length context)))) + (cl-loop with n = 0 + ;; If point doesn't move, we're at the root. + for point-start = (point) + do (sgml-skip-tag-backward 1) + until (= (point) point-start) + ;; If depth changed, we're done. + for current-depth = (length (skewer-html--get-context)) + until (< current-depth target-depth) + ;; Examine the sibling tag. + for current-name = (save-excursion + (forward-char) + (sgml-parse-tag-name)) + when (equal current-name tag-name) + do (cl-incf n) + finally return n))))))) + +(defun skewer-html-compute-tag-ancestry () + "Compute the ancestry chain at point." + (skewer-html--with-html-mode + (nreverse + (cl-loop for tag in (skewer-html--get-context) + for nth = (skewer-html-compute-tag-nth (1+ (sgml-tag-start tag))) + for name = (skewer-html--cleanup tag) + unless (equal name "html") + collect (list name nth))))) + +(defun skewer-html-compute-selector () + "Compute the selector for exactly the tag around point." + (let ((ancestry (skewer-html-compute-tag-ancestry))) + (mapconcat (lambda (tag) + (format "%s:nth-of-type(%d)" (cl-first tag) (cl-second tag))) + ancestry " > "))) + +;; Fetching + +(defun skewer-html-fetch-selector (selector) + "Fetch the innerHTML of a selector." + (let ((result (skewer-eval-synchronously selector :type "fetchselector"))) + (if (skewer-success-p result) + (cdr (assoc 'value result)) + ""))) + +(defun skewer-html-fetch-selector-into-buffer (selector) + "Fetch the innerHTML of a selector and insert it into the active buffer." + (interactive "sSelector: ") + (insert (skewer-html-fetch-selector selector))) + +;; Evaluation + +(defun skewer-html-eval (string ancestry &optional append) + "Load HTML into a selector, optionally appending." + (let ((ancestry* (cl-coerce ancestry 'vector))) ; for JSON + (skewer-eval string nil :type "html" :extra `((ancestry . ,ancestry*) + (append . ,append))))) + +(defun skewer-html-eval-tag () + "Load HTML from the immediately surrounding tag." + (interactive) + (let ((ancestry (skewer-html-compute-tag-ancestry))) + (save-excursion + ;; Move to beginning of opening tag + (let* ((beg (skewer-html--with-html-mode + (sgml-skip-tag-forward 1) (point))) + (end (skewer-html--with-html-mode + (sgml-skip-tag-backward 1) (point))) + (region (buffer-substring-no-properties beg end))) + (skewer-flash-region beg end) + (if (= (length ancestry) 1) + (error "Error: cannot eval body and head tags.") + (skewer-html-eval region ancestry nil)))))) + +;; Minor mode definition + +(defvar skewer-html-mode-map + (let ((map (make-sparse-keymap))) + (prog1 map + (define-key map (kbd "C-M-x") 'skewer-html-eval-tag))) + "Keymap for skewer-html-mode") + +;;;###autoload +(define-minor-mode skewer-html-mode + "Minor mode for interactively loading new HTML." + :lighter " skewer-html" + :keymap skewer-html-mode-map + :group 'skewer) + +(provide 'skewer-html) + +;;; skewer-html.el ends here |