1 # markdown is released under the BSD license 2 # Copyright 2007, 2008 The Python Markdown Project (v. 1.7 and later) 3 # Copyright 2004, 2005, 2006 Yuri Takhteyev (v. 0.2-1.6b) 4 # Copyright 2004 Manfred Stienstra (the original version) 5 # 6 # All rights reserved. 7 # 8 # Redistribution and use in source and binary forms, with or without 9 # modification, are permitted provided that the following conditions are met: 10 # 11 # * Redistributions of source code must retain the above copyright 12 # notice, this list of conditions and the following disclaimer. 13 # * Redistributions in binary form must reproduce the above copyright 14 # notice, this list of conditions and the following disclaimer in the 15 # documentation and/or other materials provided with the distribution. 16 # * Neither the name of the <organization> nor the 17 # names of its contributors may be used to endorse or promote products 18 # derived from this software without specific prior written permission. 19 # 20 # THIS SOFTWARE IS PROVIDED BY THE PYTHON MARKDOWN PROJECT ''AS IS'' AND ANY 21 # EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 22 # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 23 # DISCLAIMED. IN NO EVENT SHALL ANY CONTRIBUTORS TO THE PYTHON MARKDOWN PROJECT 24 # BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 # POSSIBILITY OF SUCH DAMAGE. 31 32 33 from __future__ import unicode_literals 34 from __future__ import absolute_import 35 from . import util 36 from . import odict 37 38 class State(list): 39 """ Track the current and nested state of the parser. 40 41 This utility class is used to track the state of the BlockParser and 42 support multiple levels if nesting. It's just a simple API wrapped around 43 a list. Each time a state is set, that state is appended to the end of the 44 list. Each time a state is reset, that state is removed from the end of 45 the list. 46 47 Therefore, each time a state is set for a nested block, that state must be 48 reset when we back out of that level of nesting or the state could be 49 corrupted. 50 51 While all the methods of a list object are available, only the three 52 defined below need be used. 53 54 """ 55 56 def set(self, state): 57 """ Set a new state. """ 58 self.append(state) 59 60 def reset(self): 61 """ Step back one step in nested state. """ 62 self.pop() 63 64 def isstate(self, state): 65 """ Test that top (current) level is of given state. """ 66 if len(self): 67 return self[-1] == state 68 else: 69 return False 70 71 class BlockParser: 72 """ Parse Markdown blocks into an ElementTree object. 73 74 A wrapper class that stitches the various BlockProcessors together, 75 looping through them and creating an ElementTree object. 76 """ 77 78 def __init__(self, markdown): 79 self.blockprocessors = odict.OrderedDict() 80 self.state = State() 81 self.markdown = markdown 82 83 def parseDocument(self, lines): 84 """ Parse a markdown document into an ElementTree. 85 86 Given a list of lines, an ElementTree object (not just a parent Element) 87 is created and the root element is passed to the parser as the parent. 88 The ElementTree object is returned. 89 90 This should only be called on an entire document, not pieces. 91 92 """ 93 # Create a ElementTree from the lines 94 self.root = util.etree.Element(self.markdown.doc_tag) 95 self.parseChunk(self.root, '\n'.join(lines)) 96 return util.etree.ElementTree(self.root) 97 98 def parseChunk(self, parent, text): 99 """ Parse a chunk of markdown text and attach to given etree node. 100 101 While the ``text`` argument is generally assumed to contain multiple 102 blocks which will be split on blank lines, it could contain only one 103 block. Generally, this method would be called by extensions when 104 block parsing is required. 105 106 The ``parent`` etree Element passed in is altered in place. 107 Nothing is returned. 108 109 """ 110 self.parseBlocks(parent, text.split('\n\n')) 111 112 def parseBlocks(self, parent, blocks): 113 """ Process blocks of markdown text and attach to given etree node. 114 115 Given a list of ``blocks``, each blockprocessor is stepped through 116 until there are no blocks left. While an extension could potentially 117 call this method directly, it's generally expected to be used internally. 118 119 This is a public method as an extension may need to add/alter additional 120 BlockProcessors which call this method to recursively parse a nested 121 block. 122 123 """ 124 while blocks: 125 for processor in self.blockprocessors.values(): 126 if processor.test(parent, blocks[0]): 127 if processor.run(parent, blocks) is not False: 128 # run returns True or None 129 break 130 131 132
