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Diffstat (limited to 'emacs.d/vendor/reason-indent.el')
| -rw-r--r-- | emacs.d/vendor/reason-indent.el | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/emacs.d/vendor/reason-indent.el b/emacs.d/vendor/reason-indent.el new file mode 100644 index 000000000000..8fd3c9425866 --- /dev/null +++ b/emacs.d/vendor/reason-indent.el @@ -0,0 +1,304 @@ +;;; reason-indent.el --- Indentation functions for ReasonML -*-lexical-binding: t-*- + +;; Portions Copyright (c) 2015-present, Facebook, Inc. All rights reserved. + +;;; Commentary: + +;; Indentation functions for Reason. + +;;; Code: + +(defconst reason-re-ident "[[:word:][:multibyte:]_][[:word:][:multibyte:]_[:digit:]]*") + +(defcustom reason-indent-offset 2 + "Indent Reason code by this number of spaces." + :type 'integer + :group 'reason-mode + :safe #'integerp) + +(defun reason-looking-back-str (str) + "Like `looking-back' but for fixed strings rather than regexps. +Works around some regexp slowness. +Argument STR string to search for." + (let ((len (length str))) + (and (> (point) len) + (equal str (buffer-substring-no-properties (- (point) len) (point)))))) + +(defun reason-paren-level () + "Get the level of nesting inside parentheses." + (nth 0 (syntax-ppss))) + +(defun reason-in-str-or-cmnt () + "Return whether point is currently inside a string or a comment." + (nth 8 (syntax-ppss))) + +(defun reason-rewind-past-str-cmnt () + "Rewind past string or comment." + (goto-char (nth 8 (syntax-ppss)))) + +(defun reason-rewind-irrelevant () + "Rewind past irrelevant characters (whitespace of inside comments)." + (interactive) + (let ((starting (point))) + (skip-chars-backward "[:space:]\n") + (if (reason-looking-back-str "*/") (backward-char)) + (if (reason-in-str-or-cmnt) + (reason-rewind-past-str-cmnt)) + (if (/= starting (point)) + (reason-rewind-irrelevant)))) + +(defun reason-align-to-expr-after-brace () + "Align the expression at point to the expression after the previous brace." + (save-excursion + (forward-char) + ;; We don't want to indent out to the open bracket if the + ;; open bracket ends the line + (when (not (looking-at "[[:blank:]]*\\(?://.*\\)?$")) + (when (looking-at "[[:space:]]") + (forward-word 1) + (backward-word 1)) + (current-column)))) + +(defun reason-align-to-prev-expr () + "Align the expression at point to the previous expression." + (let ((alignment (save-excursion + (forward-char) + ;; We don't want to indent out to the open bracket if the + ;; open bracket ends the line + (when (not (looking-at "[[:blank:]]*\\(?://.*\\)?$")) + (if (looking-at "[[:space:]]") + (progn + (forward-word 1) + (backward-word 1)) + (backward-char)) + (current-column))))) + (if (not alignment) + (save-excursion + (forward-char) + (forward-line) + (back-to-indentation) + (current-column)) + alignment))) + +;;; Start of a reason binding +(defvar reason-binding + (regexp-opt '("let" "type" "module" "fun"))) + +(defun reason-beginning-of-defun (&optional arg) + "Move backward to the beginning of the current defun. + +With ARG, move backward multiple defuns. Negative ARG means +move forward. + +This is written mainly to be used as `beginning-of-defun-function'. +Don't move to the beginning of the line. `beginning-of-defun', +which calls this, does that afterwards." + (interactive "p") + (re-search-backward (concat "^\\(" reason-binding "\\)\\_>") + nil 'move (or arg 1))) + +(defun reason-end-of-defun () + "Move forward to the next end of defun. + +With argument, do it that many times. +Negative argument -N means move back to Nth preceding end of defun. + +Assume that this is called after ‘beginning-of-defun’. So point is +at the beginning of the defun body. + +This is written mainly to be used as `end-of-defun-function' for Reason." + (interactive) + ;; Find the opening brace + (if (re-search-forward "[{]" nil t) + (progn + (goto-char (match-beginning 0)) + ;; Go to the closing brace + (condition-case nil + (forward-sexp) + (scan-error + ;; The parentheses are unbalanced; instead of being unable to fontify, just jump to the end of the buffer + (goto-char (point-max))))) + ;; There is no opening brace, so consider the whole buffer to be one "defun" + (goto-char (point-max)))) + +(defun reason-rewind-to-beginning-of-current-level-expr () + "Rewind to the beginning of the expression on the current level of nesting." + (interactive) + (let ((current-level (reason-paren-level))) + (back-to-indentation) + (when (looking-at "=>") + (reason-rewind-irrelevant) + (back-to-indentation)) + (while (> (reason-paren-level) current-level) + (backward-up-list) + (back-to-indentation)))) + +(defun reason-mode-indent-line () + "Indent current line." + (interactive) + (let ((indent + (save-excursion + (back-to-indentation) + ;; Point is now at beginning of current line + (let* ((level (reason-paren-level)) + (baseline + ;; Our "baseline" is one level out from the indentation of the expression + ;; containing the innermost enclosing opening bracket. That + ;; way if we are within a block that has a different + ;; indentation than this mode would give it, we still indent + ;; the inside of it correctly relative to the outside. + (if (= 0 level) + 0 + (save-excursion + (reason-rewind-irrelevant) + (if (save-excursion + (reason-rewind-to-beginning-of-current-level-expr) + (looking-at "<")) + (progn + (reason-rewind-to-beginning-of-current-level-expr) + (current-column)) + (progn + (backward-up-list) + (reason-rewind-to-beginning-of-current-level-expr) + + (cond + ((looking-at "switch") + (current-column)) + + ((looking-at "|") + (+ (current-column) (* reason-indent-offset 2))) + + (t + (let ((current-level (reason-paren-level))) + (save-excursion + (while (and (= current-level (reason-paren-level)) + (not (looking-at reason-binding))) + (reason-rewind-irrelevant) + (reason-rewind-to-beginning-of-current-level-expr)) + (+ (current-column) reason-indent-offset))))))))))) + (cond + ;; A function return type is indented to the corresponding function arguments + ((looking-at "=>") + (+ baseline reason-indent-offset)) + + ((reason-in-str-or-cmnt) + (cond + ;; In the end of the block -- align with star + ((looking-at "*/") (+ baseline 1)) + ;; Indent to the following shape: + ;; /* abcd + ;; * asdf + ;; */ + ;; + ((looking-at "*") (+ baseline 1)) + ;; Indent to the following shape: + ;; /* abcd + ;; asdf + ;; */ + ;; + (t (+ baseline (+ reason-indent-offset 1))))) + + ((looking-at "</") (- baseline reason-indent-offset)) + + ;; A closing brace is 1 level unindented + ((looking-at "}\\|)\\|\\]") + (save-excursion + (reason-rewind-irrelevant) + (let ((jsx? (reason-looking-back-str ">"))) + (backward-up-list) + (reason-rewind-to-beginning-of-current-level-expr) + (cond + ((looking-at "switch") baseline) + + (jsx? (current-column)) + + (t (- baseline reason-indent-offset)))))) + + ;; Doc comments in /** style with leading * indent to line up the *s + ((and (nth 4 (syntax-ppss)) (looking-at "*")) + (+ 1 baseline)) + + ;; If we're in any other token-tree / sexp, then: + (t + (or + ;; If we are inside a pair of braces, with something after the + ;; open brace on the same line and ending with a comma, treat + ;; it as fields and align them. + (when (> level 0) + (save-excursion + (reason-rewind-irrelevant) + (backward-up-list) + ;; Point is now at the beginning of the containing set of braces + (reason-align-to-expr-after-brace))) + + (progn + (back-to-indentation) + (cond ((looking-at (regexp-opt '("and" "type"))) + baseline) + ((save-excursion + (reason-rewind-irrelevant) + (= (point) 1)) + baseline) + ((save-excursion + (while (looking-at "|") + (reason-rewind-irrelevant) + (back-to-indentation)) + (looking-at (regexp-opt '("type")))) + (+ baseline reason-indent-offset)) + ((looking-at "|\\|/[/*]") + baseline) + ((and (> level 0) + (save-excursion + (reason-rewind-irrelevant) + (backward-up-list) + (reason-rewind-to-beginning-of-current-level-expr) + (looking-at "switch"))) + (+ baseline reason-indent-offset)) + ((save-excursion + (reason-rewind-irrelevant) + (looking-back "[{;,\\[(]" (- (point) 2))) + baseline) + ((and + (save-excursion + (reason-rewind-irrelevant) + (reason-rewind-to-beginning-of-current-level-expr) + (and (looking-at reason-binding) + (not (progn + (forward-sexp) + (forward-sexp) + (skip-chars-forward "[:space:]\n") + (looking-at "="))))) + (not (save-excursion + (skip-chars-backward "[:space:]\n") + (reason-looking-back-str "=>")))) + (save-excursion + (reason-rewind-irrelevant) + (backward-sexp) + (reason-align-to-prev-expr))) + ((save-excursion + (reason-rewind-irrelevant) + (looking-back "<\/.*?>" (- (point) 30))) + baseline) + (t + (save-excursion + (reason-rewind-irrelevant) + (reason-rewind-to-beginning-of-current-level-expr) + + (if (looking-at "|") + baseline + (+ baseline reason-indent-offset))))) + ;; Point is now at the beginning of the current line + )))))))) + + (when indent + ;; If we're at the beginning of the line (before or at the current + ;; indentation), jump with the indentation change. Otherwise, save the + ;; excursion so that adding the indentations will leave us at the + ;; equivalent position within the line to where we were before. + (if (<= (current-column) (current-indentation)) + (indent-line-to indent) + (save-excursion (indent-line-to indent)))))) + +(provide 'reason-indent) + +;;; reason-indent.el ends here |