Add a javascript syntax highlighter

src/calibre/gui2/tweak_book/editor/syntax/javascript.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python
+# vim:fileencoding=utf-8
+from __future__ import (unicode_literals, division, absolute_import,
+                        print_function)
+
+__license__ = 'GPL v3'
+__copyright__ = '2014, Kovid Goyal <kovid at kovidgoyal.net>'
+
+import re
+
+from pygments.lexer import RegexLexer, default, include
+from pygments.token import Comment, Punctuation, Number, Keyword, Text, String, Operator, Name
+import pygments.unistring as uni
+
+from calibre.gui2.tweak_book.editor.syntax.pygments_highlighter import create_highlighter
+
+JS_IDENT_START = ('(?:[$_' + uni.combine('Lu', 'Ll', 'Lt', 'Lm', 'Lo', 'Nl') +
+                  ']|\\\\u[a-fA-F0-9]{4})')
+JS_IDENT_PART = ('(?:[$' + uni.combine('Lu', 'Ll', 'Lt', 'Lm', 'Lo', 'Nl',
+                                       'Mn', 'Mc', 'Nd', 'Pc') +
+                 u'\u200c\u200d]|\\\\u[a-fA-F0-9]{4})')
+JS_IDENT = JS_IDENT_START + '(?:' + JS_IDENT_PART + ')*'
+
+class JavascriptLexer(RegexLexer):
+
+    """
+    For JavaScript source code. This is based on the pygments JS highlighter,
+    bu that does not handle multi-line comments in streaming mode, so we had to
+    modify it.
+    """
+
+    flags = re.DOTALL | re.UNICODE | re.MULTILINE
+
+    tokens = {
+        b'commentsandwhitespace': [
+            (r'\s+', Text),
+            (r'<!--', Comment),
+            (r'//.*?$', Comment.Single),
+            (r'/\*', Comment.Multiline, b'comment')
+        ],
+        b'comment': [
+            (r'[^*/]+', Comment.Multiline),
+            (r'\*/', Comment.Multiline, b'#pop'),
+            (r'[*/]', Comment.Multiline),
+        ],
+        b'slashstartsregex': [
+            include(b'commentsandwhitespace'),
+            (r'/(\\.|[^[/\\\n]|\[(\\.|[^\]\\\n])*])+/'
+             r'([gim]+\b|\B)', String.Regex, b'#pop'),
+            (r'(?=/)', Text, (b'#pop', b'badregex')),
+            default(b'#pop')
+        ],
+        b'badregex': [
+            (r'\n', Text, b'#pop')
+        ],
+        b'root': [
+            (r'\A#! ?/.*?\n', Comment),  # shebang lines are recognized by node.js
+            (r'^(?=\s|/|<!--)', Text, b'slashstartsregex'),
+            include(b'commentsandwhitespace'),
+            (r'\+\+|--|~|&&|\?|:|\|\||\\(?=\n)|'
+             r'(<<|>>>?|==?|!=?|[-<>+*%&|^/])=?', Operator, b'slashstartsregex'),
+            (r'[{(\[;,]', Punctuation, b'slashstartsregex'),
+            (r'[})\].]', Punctuation),
+            (r'(for|in|while|do|break|return|continue|switch|case|default|if|else|'
+             r'throw|try|catch|finally|new|delete|typeof|instanceof|void|yield|'
+             r'this)\b', Keyword, b'slashstartsregex'),
+            (r'(var|let|with|function)\b', Keyword.Declaration, b'slashstartsregex'),
+            (r'(abstract|boolean|byte|char|class|const|debugger|double|enum|export|'
+             r'extends|final|float|goto|implements|import|int|interface|long|native|'
+             r'package|private|protected|public|short|static|super|synchronized|throws|'
+             r'transient|volatile)\b', Keyword.Reserved),
+            (r'(true|false|null|NaN|Infinity|undefined)\b', Keyword.Constant),
+            (r'(Array|Boolean|Date|Error|Function|Math|netscape|'
+             r'Number|Object|Packages|RegExp|String|sun|decodeURI|'
+             r'decodeURIComponent|encodeURI|encodeURIComponent|'
+             r'Error|eval|isFinite|isNaN|parseFloat|parseInt|document|this|'
+             r'window)\b', Name.Builtin),
+            (JS_IDENT, Name.Other),
+            (r'[0-9][0-9]*\.[0-9]+([eE][0-9]+)?[fd]?', Number.Float),
+            (r'0x[0-9a-fA-F]+', Number.Hex),
+            (r'[0-9]+', Number.Integer),
+            (r'"(\\\\|\\"|[^"])*"', String.Double),
+            (r"'(\\\\|\\'|[^'])*'", String.Single),
+        ]
+    }
+
+
+Highlighter = create_highlighter('JavascriptHighlighter', JavascriptLexer)
+
+if __name__ == '__main__':
+    from calibre.gui2.tweak_book.editor.widget import launch_editor
+    launch_editor(P('viewer/images.js'), syntax='javascript')

src/calibre/gui2/tweak_book/editor/syntax/python.py

@@ -10,7 +10,7 @@ from pygments.lexers import PythonLexer
 
 from calibre.gui2.tweak_book.editor.syntax.pygments_highlighter import create_highlighter
 
-PythonHighlighter = create_highlighter('PythonHighlighter', PythonLexer)
+Highlighter = create_highlighter('PythonHighlighter', PythonLexer)
 
 if __name__ == '__main__':
     import os

src/calibre/gui2/tweak_book/editor/text.py

@@ -6,7 +6,7 @@ from __future__ import (unicode_literals, division, absolute_import,
 __license__ = 'GPL v3'
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
-import re
+import re, importlib
 import textwrap, unicodedata
 from future_builtins import map
 
@@ -39,12 +39,10 @@ def get_highlighter(syntax):
     ans = {'html':HTMLHighlighter, 'css':CSSHighlighter, 'xml':XMLHighlighter}.get(syntax, SyntaxHighlighter)
     if ans is SyntaxHighlighter:
         # Load these highlighters only on demand
-        if syntax == 'python':
+        try:
-            try:
+            ans = importlib.import_module('calibre.gui2.tweak_book.editor.syntax.' + syntax).Highlighter
-                from calibre.gui2.tweak_book.editor.syntax.python import PythonHighlighter
+        except (ImportError, AttributeError):
-                ans = PythonHighlighter
+            pass
-            except ImportError:
-                pass  # For people running from source
     return ans
 
 _dff = None