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third_party/Python-Markdown/markdown/extensions/smarty.py

Index: third_party/Python-Markdown/markdown/extensions/smarty.py
diff --git a/third_party/Python-Markdown/markdown/extensions/smarty.py b/third_party/Python-Markdown/markdown/extensions/smarty.py
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+# -*- coding: utf-8 -*-
+'''
+Smarty extension for Python-Markdown
+====================================
+
+Adds conversion of ASCII dashes, quotes and ellipses to their HTML
+entity equivalents.
+
+See <https://pythonhosted.org/Markdown/extensions/smarty.html>
+for documentation.
+
+Author: 2013, Dmitry Shachnev <mitya57@gmail.com>
+
+All changes Copyright 2013-2014 The Python Markdown Project
+
+License: [BSD](http://www.opensource.org/licenses/bsd-license.php)
+
+SmartyPants license:
+
+   Copyright (c) 2003 John Gruber <http://daringfireball.net/>
+   All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+   *  Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+   *  Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the
+      distribution.
+
+   *  Neither the name "SmartyPants" nor the names of its contributors
+      may be used to endorse or promote products derived from this
+      software without specific prior written permission.
+
+   This software is provided by the copyright holders and contributors "as
+   is" and any express or implied warranties, including, but not limited
+   to, the implied warranties of merchantability and fitness for a
+   particular purpose are disclaimed. In no event shall the copyright
+   owner or contributors be liable for any direct, indirect, incidental,
+   special, exemplary, or consequential damages (including, but not
+   limited to, procurement of substitute goods or services; loss of use,
+   data, or profits; or business interruption) however caused and on any
+   theory of liability, whether in contract, strict liability, or tort
+   (including negligence or otherwise) arising in any way out of the use
+   of this software, even if advised of the possibility of such damage.
+
+
+smartypants.py license:
+
+   smartypants.py is a derivative work of SmartyPants.
+   Copyright (c) 2004, 2007 Chad Miller <http://web.chad.org/>
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+   *  Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+   *  Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the
+      distribution.
+
+   This software is provided by the copyright holders and contributors "as
+   is" and any express or implied warranties, including, but not limited
+   to, the implied warranties of merchantability and fitness for a
+   particular purpose are disclaimed. In no event shall the copyright
+   owner or contributors be liable for any direct, indirect, incidental,
+   special, exemplary, or consequential damages (including, but not
+   limited to, procurement of substitute goods or services; loss of use,
+   data, or profits; or business interruption) however caused and on any
+   theory of liability, whether in contract, strict liability, or tort
+   (including negligence or otherwise) arising in any way out of the use
+   of this software, even if advised of the possibility of such damage.
+
+'''
+
+
+from __future__ import unicode_literals
+from . import Extension
+from ..inlinepatterns import HtmlPattern
+from ..odict import OrderedDict
+from ..treeprocessors import InlineProcessor
+
+
+# Constants for quote education.
+punctClass = r"""[!"#\$\%'()*+,-.\/:;<=>?\@\[\\\]\^_`{|}~]"""
+endOfWordClass = r"[\s.,;:!?)]"
+closeClass = "[^\ \t\r\n\[\{\(\-\u0002\u0003]"
+
+openingQuotesBase = (
+    '(\s'               # a  whitespace char
+    '|&nbsp;'           # or a non-breaking space entity
+    '|--'               # or dashes
+    '|–|—'              # or unicode
+    '|&[mn]dash;'       # or named dash entities
+    '|&#8211;|&#8212;'  # or decimal entities
+    ')'
+)
+
+substitutions = {
+    'mdash': '&mdash;',
+    'ndash': '&ndash;',
+    'ellipsis': '&hellip;',
+    'left-angle-quote': '&laquo;',
+    'right-angle-quote': '&raquo;',
+    'left-single-quote': '&lsquo;',
+    'right-single-quote': '&rsquo;',
+    'left-double-quote': '&ldquo;',
+    'right-double-quote': '&rdquo;',
+}
+
+
+# Special case if the very first character is a quote
+# followed by punctuation at a non-word-break. Close the quotes by brute force:
+singleQuoteStartRe = r"^'(?=%s\B)" % punctClass
+doubleQuoteStartRe = r'^"(?=%s\B)' % punctClass
+
+# Special case for double sets of quotes, e.g.:
+#   <p>He said, "'Quoted' words in a larger quote."</p>
+doubleQuoteSetsRe = r""""'(?=\w)"""
+singleQuoteSetsRe = r"""'"(?=\w)"""
+
+# Special case for decade abbreviations (the '80s):
+decadeAbbrRe = r"(?<!\w)'(?=\d{2}s)"
+
+# Get most opening double quotes:
+openingDoubleQuotesRegex = r'%s"(?=\w)' % openingQuotesBase
+
+# Double closing quotes:
+closingDoubleQuotesRegex = r'"(?=\s)'
+closingDoubleQuotesRegex2 = '(?<=%s)"' % closeClass
+
+# Get most opening single quotes:
+openingSingleQuotesRegex = r"%s'(?=\w)" % openingQuotesBase
+
+# Single closing quotes:
+closingSingleQuotesRegex = r"(?<=%s)'(?!\s|s\b|\d)" % closeClass
+closingSingleQuotesRegex2 = r"(?<=%s)'(\s|s\b)" % closeClass
+
+# All remaining quotes should be opening ones
+remainingSingleQuotesRegex = "'"
+remainingDoubleQuotesRegex = '"'
+
+
+class SubstituteTextPattern(HtmlPattern):
+    def __init__(self, pattern, replace, markdown_instance):
+        """ Replaces matches with some text. """
+        HtmlPattern.__init__(self, pattern)
+        self.replace = replace
+        self.markdown = markdown_instance
+
+    def handleMatch(self, m):
+        result = ''
+        for part in self.replace:
+            if isinstance(part, int):
+                result += m.group(part)
+            else:
+                result += self.markdown.htmlStash.store(part, safe=True)
+        return result
+
+
+class SmartyExtension(Extension):
+    def __init__(self, *args, **kwargs):
+        self.config = {
+            'smart_quotes': [True, 'Educate quotes'],
+            'smart_angled_quotes': [False, 'Educate angled quotes'],
+            'smart_dashes': [True, 'Educate dashes'],
+            'smart_ellipses': [True, 'Educate ellipses'],
+            'substitutions': [{}, 'Overwrite default substitutions'],
+        }
+        super(SmartyExtension, self).__init__(*args, **kwargs)
+        self.substitutions = dict(substitutions)
+        self.substitutions.update(self.getConfig('substitutions', default={}))
+
+    def _addPatterns(self, md, patterns, serie):
+        for ind, pattern in enumerate(patterns):
+            pattern += (md,)
+            pattern = SubstituteTextPattern(*pattern)
+            after = ('>smarty-%s-%d' % (serie, ind - 1) if ind else '_begin')
+            name = 'smarty-%s-%d' % (serie, ind)
+            self.inlinePatterns.add(name, pattern, after)
+
+    def educateDashes(self, md):
+        emDashesPattern = SubstituteTextPattern(
+            r'(?<!-)---(?!-)', (self.substitutions['mdash'],), md
+        )
+        enDashesPattern = SubstituteTextPattern(
+            r'(?<!-)--(?!-)', (self.substitutions['ndash'],), md
+        )
+        self.inlinePatterns.add('smarty-em-dashes', emDashesPattern, '_begin')
+        self.inlinePatterns.add(
+            'smarty-en-dashes', enDashesPattern, '>smarty-em-dashes'
+        )
+
+    def educateEllipses(self, md):
+        ellipsesPattern = SubstituteTextPattern(
+            r'(?<!\.)\.{3}(?!\.)', (self.substitutions['ellipsis'],), md
+        )
+        self.inlinePatterns.add('smarty-ellipses', ellipsesPattern, '_begin')
+
+    def educateAngledQuotes(self, md):
+        leftAngledQuotePattern = SubstituteTextPattern(
+            r'\<\<', (self.substitutions['left-angle-quote'],), md
+        )
+        rightAngledQuotePattern = SubstituteTextPattern(
+            r'\>\>', (self.substitutions['right-angle-quote'],), md
+        )
+        self.inlinePatterns.add(
+            'smarty-left-angle-quotes', leftAngledQuotePattern, '_begin'
+        )
+        self.inlinePatterns.add(
+            'smarty-right-angle-quotes',
+            rightAngledQuotePattern,
+            '>smarty-left-angle-quotes'
+        )
+
+    def educateQuotes(self, md):
+        lsquo = self.substitutions['left-single-quote']
+        rsquo = self.substitutions['right-single-quote']
+        ldquo = self.substitutions['left-double-quote']
+        rdquo = self.substitutions['right-double-quote']
+        patterns = (
+            (singleQuoteStartRe, (rsquo,)),
+            (doubleQuoteStartRe, (rdquo,)),
+            (doubleQuoteSetsRe, (ldquo + lsquo,)),
+            (singleQuoteSetsRe, (lsquo + ldquo,)),
+            (decadeAbbrRe, (rsquo,)),
+            (openingSingleQuotesRegex, (2, lsquo)),
+            (closingSingleQuotesRegex, (rsquo,)),
+            (closingSingleQuotesRegex2, (rsquo, 2)),
+            (remainingSingleQuotesRegex, (lsquo,)),
+            (openingDoubleQuotesRegex, (2, ldquo)),
+            (closingDoubleQuotesRegex, (rdquo,)),
+            (closingDoubleQuotesRegex2, (rdquo,)),
+            (remainingDoubleQuotesRegex, (ldquo,))
+        )
+        self._addPatterns(md, patterns, 'quotes')
+
+    def extendMarkdown(self, md, md_globals):
+        configs = self.getConfigs()
+        self.inlinePatterns = OrderedDict()
+        if configs['smart_ellipses']:
+            self.educateEllipses(md)
+        if configs['smart_quotes']:
+            self.educateQuotes(md)
+        if configs['smart_angled_quotes']:
+            self.educateAngledQuotes(md)
+        if configs['smart_dashes']:
+            self.educateDashes(md)
+        inlineProcessor = InlineProcessor(md)
+        inlineProcessor.inlinePatterns = self.inlinePatterns
+        md.treeprocessors.add('smarty', inlineProcessor, '_end')
+        md.ESCAPED_CHARS.extend(['"', "'"])
+
+
+def makeExtension(*args, **kwargs):
+    return SmartyExtension(*args, **kwargs)