diff .elisp/yaml-mode.el @ 52:d6ea7c108453

Add yaml mode.
author Augie Fackler <durin42@gmail.com>
date Thu, 19 Feb 2009 09:19:18 -0600
parents
children
line wrap: on
line diff
new file mode 100644
--- /dev/null
+++ b/.elisp/yaml-mode.el
@@ -0,0 +1,392 @@
+;;; yaml-mode.el --- Major mode for editing YAML files
+
+;; Copyright (C) 2006  Yoshiki Kurihara
+
+;; Author: Yoshiki Kurihara <kurihara@cpan.org>
+;;         Marshall T. Vandegrift <llasram@gmail.com>
+;; Keywords: data yaml
+;; Version: 0.0.3
+
+;; This file is not part of Emacs
+
+;; This file is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; This file is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING.  If not, write to
+;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+
+;; This is a major mode for editing files in the YAML data
+;; serialization format.  It was initially developed by Yoshiki
+;; Kurihara and many features were added by Marshall Vandegrift.  As
+;; YAML and Python share the fact that indentation determines
+;; structure, this mode provides indentation and indentation command
+;; behavior very similar to that of python-mode.
+
+;;; Installation:
+
+;; To install, just drop this file into a directory in your
+;; `load-path' and (optionally) byte-compile it.  To automatically
+;; handle files ending in '.yml', add something like:
+;;
+;;    (require 'yaml-mode)
+;;    (add-to-list 'auto-mode-alist '("\\.yml$" . yaml-mode))
+;;
+;; to your .emacs file.
+;;
+;; Unlike python-mode, this mode follows the Emacs convention of not
+;; binding the ENTER key to `newline-and-indent'.  To get this
+;; behavior, add the key definition to `yaml-mode-hook':
+;;
+;;    (add-hook 'yaml-mode-hook
+;;     '(lambda ()
+;;        (define-key yaml-mode-map "\C-m" 'newline-and-indent)))
+
+;;; Known Bugs:
+
+;; YAML is easy to write but complex to parse, and this mode doesn't
+;; even really try.  Indentation and highlighting will break on
+;; abnormally complicated structures.
+
+;;; Code:
+
+
+;; User definable variables
+
+(defgroup yaml nil
+  "Support for the YAML serialization format"
+  :group 'languages
+  :prefix "yaml-")
+
+(defcustom yaml-mode-hook nil
+  "*Hook run by `yaml-mode'."
+  :type 'hook
+  :group 'yaml)
+
+(defcustom yaml-indent-offset 2
+  "*Amount of offset per level of indentation."
+  :type 'integer
+  :group 'yaml)
+
+(defcustom yaml-backspace-function 'backward-delete-char-untabify
+  "*Function called by `yaml-electric-backspace' when deleting backwards."
+  :type 'function
+  :group 'yaml)
+
+(defcustom yaml-block-literal-search-lines 100
+  "*Maximum number of lines to search for start of block literals."
+  :type 'integer
+  :group 'yaml)
+
+(defcustom yaml-block-literal-electric-alist
+  '((?| . "") (?> . "-"))
+  "*Characters for which to provide electric behavior.
+The association list key should be a key code and the associated value
+should be a string containing additional characters to insert when
+that key is pressed to begin a block literal."
+  :type 'alist
+  :group 'yaml)
+
+(defface yaml-tab-face
+   '((((class color)) (:background "red" :foreground "red" :bold t))
+     (t (:reverse-video t)))
+  "Face to use for highlighting tabs in YAML files."
+  :group 'faces
+  :group 'yaml)
+
+
+;; Constants
+
+(defconst yaml-mode-version "0.0.3" "Version of `yaml-mode.'")
+
+(defconst yaml-blank-line-re "^ *$"
+  "Regexp matching a line containing only (valid) whitespace.")
+
+(defconst yaml-comment-re "\\(#*.*\\)"
+  "Regexp matching a line containing a YAML comment or delimiter.")
+
+(defconst yaml-directive-re "^\\(?:--- \\)? *%\\(\\w+\\)"
+  "Regexp matching a line contatining a YAML directive.")
+
+(defconst yaml-document-delimiter-re "^ *\\(?:---\\|[.][.][.]\\)"
+  "Rexexp matching a YAML document delimiter line.")
+
+(defconst yaml-node-anchor-alias-re "[&*]\\w+"
+  "Regexp matching a YAML node anchor or alias.")
+
+(defconst yaml-tag-re "!!?[^ \n]+"
+  "Rexexp matching a YAML tag.")
+
+(defconst yaml-bare-scalar-re
+  "\\(?:[^-:,#!\n{\\[ ]\\|[^#!\n{\\[ ]\\S-\\)[^#\n]*?"
+  "Rexexp matching a YAML bare scalar.")
+
+(defconst yaml-hash-key-re
+  (concat "\\(?:^\\(?:--- \\)?\\|{\\|\\(?:[-,] +\\)+\\) *"
+          "\\(?:" yaml-tag-re " +\\)?"
+          "\\(" yaml-bare-scalar-re "\\) *:"
+          "\\(?: +\\|$\\)")
+  "Regexp matching a single YAML hash key.")
+
+(defconst yaml-scalar-context-re
+  (concat "\\(?:^\\(?:--- \\)?\\|{\\|\\(?:[-,] +\\)+\\) *"
+          "\\(?:" yaml-bare-scalar-re " *: \\)?")
+  "Regexp indicating the begininng of a scalar context.")
+
+(defconst yaml-nested-map-re
+  (concat ".*: *\\(?:&.*\\|{ *\\|" yaml-tag-re " *\\)?$")
+  "Regexp matching a line beginning a YAML nested structure.")
+
+(defconst yaml-block-literal-base-re " *[>|][-+0-9]* *\\(?:\n\\|\\'\\)"
+  "Regexp matching the substring start of a block literal.")
+
+(defconst yaml-block-literal-re
+  (concat yaml-scalar-context-re
+          "\\(?:" yaml-tag-re "\\)?"
+          yaml-block-literal-base-re)
+  "Regexp matching a line beginning a YAML block literal")
+
+(defconst yaml-nested-sequence-re
+  (concat "^\\(?: *- +\\)+"
+          "\\(?:" yaml-bare-scalar-re " *:\\(?: +.*\\)?\\)?$")
+  "Regexp matching a line containing one or more nested YAML sequences")
+
+(defconst yaml-constant-scalars-re
+  (concat "\\(?:^\\|\\(?::\\|-\\|,\\|{\\|\\[\\) +\\) *"
+          (regexp-opt
+           '("~" "null" "Null" "NULL"
+             ".nan" ".NaN" ".NAN"
+             ".inf" ".Inf" ".INF"
+             "-.inf" "-.Inf" "-.INF"
+             "y" "Y" "yes" "Yes" "YES" "n" "N" "no" "No" "NO"
+             "true" "True" "TRUE" "false" "False" "FALSE"
+             "on" "On" "ON" "off" "Off" "OFF") t)
+          " *$")
+  "Regexp matching certain scalar constants in scalar context")
+
+
+;; Mode setup
+
+(defvar yaml-mode-map ()
+  "Keymap used in `yaml-mode' buffers.")
+(if yaml-mode-map
+    nil
+  (setq yaml-mode-map (make-sparse-keymap))
+  (define-key yaml-mode-map "|" 'yaml-electric-bar-and-angle)
+  (define-key yaml-mode-map ">" 'yaml-electric-bar-and-angle)
+  (define-key yaml-mode-map "-" 'yaml-electric-dash-and-dot)
+  (define-key yaml-mode-map "." 'yaml-electric-dash-and-dot)
+  (define-key yaml-mode-map [backspace] 'yaml-electric-backspace)
+  (define-key yaml-mode-map "\C-j" 'newline-and-indent))
+
+(defvar yaml-mode-syntax-table nil
+  "Syntax table in use in yaml-mode buffers.")
+(if yaml-mode-syntax-table
+    nil
+  (setq yaml-mode-syntax-table (make-syntax-table))
+  (modify-syntax-entry ?\' "\"" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\" "\"" yaml-mode-syntax-table)
+  (modify-syntax-entry ?# "<" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\n ">" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\\ "\\" yaml-mode-syntax-table)
+  (modify-syntax-entry ?- "." yaml-mode-syntax-table)
+  (modify-syntax-entry ?_ "_" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\( "." yaml-mode-syntax-table)
+  (modify-syntax-entry ?\) "." yaml-mode-syntax-table)
+  (modify-syntax-entry ?\{ "(}" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\} "){" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\[ "(]" yaml-mode-syntax-table)
+  (modify-syntax-entry ?\] ")[" yaml-mode-syntax-table))
+
+(define-derived-mode yaml-mode fundamental-mode "YAML"
+  "Simple mode to edit YAML.
+
+\\{yaml-mode-map}"
+  (set (make-local-variable 'comment-start) "# ")
+  (set (make-local-variable 'comment-start-skip) "#+ *")
+  (set (make-local-variable 'indent-line-function) 'yaml-indent-line)
+  (set (make-local-variable 'font-lock-defaults)
+       '(yaml-font-lock-keywords
+         nil nil nil nil
+         (font-lock-syntactic-keywords . yaml-font-lock-syntactic-keywords))))
+
+
+;; Font-lock support
+
+(defvar yaml-font-lock-keywords
+   (list
+    (cons yaml-comment-re '(1 font-lock-comment-face))
+    (cons yaml-constant-scalars-re '(1 font-lock-constant-face))
+    (cons yaml-tag-re '(0 font-lock-type-face))
+    (cons yaml-node-anchor-alias-re '(0 font-lock-function-name-face t))
+    (cons yaml-hash-key-re '(1 font-lock-variable-name-face t))
+    (cons yaml-document-delimiter-re '(0 font-lock-comment-face))
+    (cons yaml-directive-re '(1 font-lock-builtin-face))
+    '(yaml-font-lock-block-literals 0 font-lock-string-face t)
+    '("^[\t]+" 0 'yaml-tab-face t))
+   "Additional expressions to highlight in YAML mode.")
+
+(defvar yaml-font-lock-syntactic-keywords
+  (list '(yaml-syntactic-block-literals 0 "." t))
+  "Additional syntax features to highlight in YAML mode.")
+
+
+(defun yaml-font-lock-block-literals (bound)
+  "Find lines within block literals.
+Find the next line of the first (if any) block literal after point and
+prior to BOUND.  Returns the beginning and end of the block literal
+line in the match data, as consumed by `font-lock-keywords' matcher
+functions.  The function begins by searching backwards to determine
+whether or not the current line is within a block literal.  This could
+be time-consuming in large buffers, so the number of lines searched is
+artificially limitted to the value of
+`yaml-block-literal-search-lines'."
+  (if (eolp) (goto-char (1+ (point))))
+  (unless (or (eobp) (>= (point) bound))
+    (let ((begin (point))
+          (end (min (1+ (point-at-eol)) bound)))
+      (goto-char (point-at-bol))
+      (while (and (looking-at yaml-blank-line-re) (not (bobp)))
+        (forward-line -1))
+      (let ((nlines yaml-block-literal-search-lines) 
+            (min-level (current-indentation))) 
+      (forward-line -1) 
+      (while (and (/= nlines 0) 
+                  (/= min-level 0) 
+                  (not (looking-at yaml-block-literal-re)) 
+                  (not (bobp))) 
+        (set 'nlines (1- nlines)) 
+        (unless (looking-at yaml-blank-line-re) 
+          (set 'min-level (min min-level (current-indentation)))) 
+        (forward-line -1)) 
+      (cond
+       ((and (< (current-indentation) min-level)
+             (looking-at yaml-block-literal-re))
+          (goto-char end) (set-match-data (list begin end)) t)
+         ((progn 
+            (goto-char begin)
+            (re-search-forward (concat yaml-block-literal-re
+                                       " *\\(.*\\)\n")
+                               bound t))
+          (set-match-data (nthcdr 2 (match-data))) t))))))
+
+(defun yaml-syntactic-block-literals (bound)
+  "Find quote characters within block literals.
+Finds the first quote character within a block literal (if any) after
+point and prior to BOUND.  Returns the position of the quote character
+in the match data, as consumed by matcher functions in
+`font-lock-syntactic-keywords'.  This allows the mode to treat ['\"]
+characters in block literals as punctuation syntax instead of string
+syntax, preventing unmatched quotes in block literals from painting
+the entire buffer in `font-lock-string-face'."
+  (let ((found nil))
+    (while (and (not found)
+                (/= (point) bound)
+                (yaml-font-lock-block-literals bound))
+      (let ((begin (match-beginning 0)) (end (match-end 0)))
+        (goto-char begin)
+        (cond
+         ((re-search-forward "['\"]" end t) (setq found t))
+         ((goto-char end)))))
+    found))
+
+
+;; Indentation and electric keys
+
+(defun yaml-compute-indentation ()
+  "Calculate the maximum sensible indentation for the current line."
+  (save-excursion
+    (beginning-of-line)
+    (if (looking-at yaml-document-delimiter-re) 0
+      (forward-line -1)
+      (while (and (looking-at yaml-blank-line-re)
+                  (> (point) (point-min)))
+        (forward-line -1))
+      (+ (current-indentation)
+         (if (looking-at yaml-nested-map-re) yaml-indent-offset 0)
+         (if (looking-at yaml-nested-sequence-re) yaml-indent-offset 0)
+         (if (looking-at yaml-block-literal-re) yaml-indent-offset 0)))))
+
+(defun yaml-indent-line ()
+  "Indent the current line.
+The first time this command is used, the line will be indented to the
+maximum sensible indentation.  Each immediately subsequent usage will
+back-dent the line by `yaml-indent-offset' spaces.  On reaching column
+0, it will cycle back to the maximum sensible indentation."
+  (interactive "*")
+  (let ((ci (current-indentation))
+        (cc (current-column))
+        (need (yaml-compute-indentation)))
+    (save-excursion
+      (beginning-of-line)
+      (delete-horizontal-space)
+      (if (and (equal last-command this-command) (/= ci 0))
+          (indent-to (* (/ (- ci 1) yaml-indent-offset) yaml-indent-offset))
+        (indent-to need)))
+      (if (< (current-column) (current-indentation))
+          (forward-to-indentation 0))))
+
+(defun yaml-electric-backspace (arg)
+  "Delete characters or back-dent the current line.
+If invoked following only whitespace on a line, will back-dent to the
+immediately previous multiple of `yaml-indent-offset' spaces."
+  (interactive "*p")
+  (if (or (/= (current-indentation) (current-column)) (bolp))
+      (funcall yaml-backspace-function arg)
+    (let ((ci (current-column)))
+      (beginning-of-line)
+      (delete-horizontal-space)
+      (indent-to (* (/ (- ci (* arg yaml-indent-offset))
+                       yaml-indent-offset)
+                    yaml-indent-offset)))))
+  
+(defun yaml-electric-bar-and-angle (arg)
+  "Insert the bound key and possibly begin a block literal.
+Inserts the bound key.  If inserting the bound key causes the current
+line to match the initial line of a block literal, then inserts the
+matching string from `yaml-block-literal-electric-alist', a newline,
+and indents appropriately."
+  (interactive "*P")
+  (self-insert-command (prefix-numeric-value arg))
+  (let ((extra-chars
+         (assoc last-command-char
+                yaml-block-literal-electric-alist)))
+    (cond
+     ((and extra-chars (not arg) (eolp)
+           (save-excursion
+             (beginning-of-line)
+             (looking-at yaml-block-literal-re)))
+      (insert (cdr extra-chars))
+      (newline-and-indent)))))
+
+(defun yaml-electric-dash-and-dot (arg)
+  "Insert the bound key and possibly de-dent line.
+Inserts the bound key.  If inserting the bound key causes the current
+line to match a document delimiter, de-dent the line to the left
+margin."
+  (interactive "*P")
+  (self-insert-command (prefix-numeric-value arg))
+  (save-excursion
+    (beginning-of-line)
+    (if (and (not arg) (looking-at yaml-document-delimiter-re))
+        (delete-horizontal-space))))
+
+(defun yaml-mode-version ()
+  "Diplay version of `yaml-mode'."
+  (interactive)
+  (message "yaml-mode %s" yaml-mode-version)
+  yaml-mode-version)
+
+(provide 'yaml-mode)
+
+;;; yaml-mode.el ends here