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import htmlentitydefs
import os
import re
import types
import mimetools
import string
from StringIO import StringIO
try:
from elementtree.ElementTree import TreeBuilder
from elementtree.ElementTree import XMLTreeBuilder
from elementtree.ElementTree import Comment
from elementtree.ElementTree import ProcessingInstruction
from elementtree.ElementTree import QName
from elementtree.ElementTree import _raise_serialization_error
from elementtree.ElementTree import _namespace_map
from elementtree.ElementTree import fixtag
from elementtree.ElementTree import parse as et_parse
from elementtree.ElementTree import ElementPath
except ImportError:
from xml.etree.ElementTree import TreeBuilder
from xml.etree.ElementTree import XMLTreeBuilder
from xml.etree.ElementTree import Comment
from xml.etree.ElementTree import ProcessingInstruction
from xml.etree.ElementTree import QName
from xml.etree.ElementTree import _raise_serialization_error
from xml.etree.ElementTree import _namespace_map
from xml.etree.ElementTree import parse as et_parse
from xml.etree.ElementTree import ElementPath
try:
from xml.etree.ElementTree import fixtag
except:
def fixtag(tag, namespaces):
# given a decorated tag (of the form {uri}tag), return prefixed
# tag and namespace declaration, if any
if isinstance(tag, QName):
tag = tag.text
namespace_uri, tag = string.split(tag[1:], "}", 1)
prefix = namespaces.get(namespace_uri)
if prefix is None:
prefix = _namespace_map.get(namespace_uri)
if prefix is None:
prefix = "ns%d" % len(namespaces)
namespaces[namespace_uri] = prefix
if prefix == "xml":
xmlns = None
else:
xmlns = ("xmlns:%s" % prefix, namespace_uri)
else:
xmlns = None
return "%s:%s" % (prefix, tag), xmlns
# HTMLTreeBuilder does not exist in python 2.5 standard elementtree
from HTMLParser import HTMLParser
AUTOCLOSE = "p", "li", "tr", "th", "td", "head", "body"
IGNOREEND = "img", "hr", "meta", "link", "br"
is_not_ascii = re.compile(eval(r'u"[\u0080-\uffff]"')).search
# replace element factory
def Replace(text, structure=False):
element = _MeldElementInterface(Replace, {})
element.text = text
element.structure = structure
return element
class IO:
def __init__(self):
self.data = ""
def write(self, data):
self.data += data
def getvalue(self):
return self.data
def clear(self):
self.data = ""
class PyHelper:
def findmeld(self, node, name, default=None):
iterator = self.getiterator(node)
for element in iterator:
val = element.attrib.get(_MELD_ID)
if val == name:
return element
return default
def clone(self, node, parent=None):
# NOTE: this is not implemented by the C version (it used to be
# but I don't want to maintain it)
element = _MeldElementInterface(node.tag, node.attrib.copy())
element.text = node.text
element.tail = node.tail
element.structure = node.structure
if parent is not None:
# avoid calling self.append to reduce function call overhead
parent._children.append(element)
element.parent = parent
for child in node._children:
self.clone(child, element)
return element
def _bfclone(self, nodes, parent):
L = []
for node in nodes:
element = _MeldElementInterface(node.tag, node.attrib.copy())
element.parent = parent
element.text = node.text
element.tail = node.tail
element.structure = node.structure
if node._children:
self._bfclone(node._children, element)
L.append(element)
parent._children = L
def bfclone(self, node, parent=None):
element = _MeldElementInterface(node.tag, node.attrib.copy())
element.text = node.text
element.tail = node.tail
element.structure = node.structure
element.parent = parent
if parent is not None:
parent._children.append(element)
if node._children:
self._bfclone(node._children, element)
return element
def getiterator(self, node, tag=None):
nodes = []
if tag == "*":
tag = None
if tag is None or node.tag == tag:
nodes.append(node)
for element in node._children:
nodes.extend(self.getiterator(element, tag))
return nodes
def content(self, node, text, structure=False):
node.text = None
replacenode = Replace(text, structure)
replacenode.parent = node
replacenode.text = text
replacenode.structure = structure
node._children = [replacenode]
pyhelper = PyHelper()
try:
import cmeld3 as chelper
except ImportError:
chelper = None
if chelper and not os.getenv('MELD3_PYIMPL'):
helper = chelper
else:
helper = pyhelper
_MELD_NS_URL = 'http://www.plope.com/software/meld3'
_MELD_PREFIX = '{%s}' % _MELD_NS_URL
_MELD_LOCAL = 'id'
_MELD_ID = '%s%s' % (_MELD_PREFIX, _MELD_LOCAL)
_MELD_SHORT_ID = 'meld:%s' % _MELD_LOCAL
_XHTML_NS_URL = 'http://www.w3.org/1999/xhtml'
_XHTML_PREFIX = '{%s}' % _XHTML_NS_URL
_XHTML_PREFIX_LEN = len(_XHTML_PREFIX)
_marker = []
class doctype:
# lookup table for ease of use in external code
html_strict = ('HTML', '-//W3C//DTD HTML 4.01//EN',
'http://www.w3.org/TR/html4/strict.dtd')
html = ('HTML', '-//W3C//DTD HTML 4.01 Transitional//EN',
'http://www.w3.org/TR/html4/loose.dtd')
xhtml_strict = ('html', '-//W3C//DTD XHTML 1.0 Strict//EN',
'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd')
xhtml = ('html', '-//W3C//DTD XHTML 1.0 Transitional//EN',
'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd')
class _MeldElementInterface:
parent = None
attrib = None
text = None
tail = None
structure = None
Replace = [Replace] # this is used by C code
# overrides to reduce MRU lookups
def __init__(self, tag, attrib):
self.tag = tag
self.attrib = attrib
self._children = []
def __repr__(self):
return "<MeldElement %s at %x>" % (self.tag, id(self))
def __len__(self):
return len(self._children)
def __getitem__(self, index):
return self._children[index]
def __getslice__(self, start, stop):
return self._children[start:stop]
def getchildren(self):
return self._children
def find(self, path):
return ElementPath.find(self, path)
def findtext(self, path, default=None):
return ElementPath.findtext(self, path, default)
def findall(self, path):
return ElementPath.findall(self, path)
def clear(self):
self.attrib.clear()
self._children = []
self.text = self.tail = None
def get(self, key, default=None):
return self.attrib.get(key, default)
def set(self, key, value):
self.attrib[key] = value
def keys(self):
return self.attrib.keys()
def items(self):
return self.attrib.items()
def getiterator(self, *ignored_args, **ignored_kw):
# we ignore any tag= passed in to us, because it's too painful
# to support in our C version
return helper.getiterator(self)
# overrides to support parent pointers and factories
def __setitem__(self, index, element):
self._children[index] = element
element.parent = self
def __setslice__(self, start, stop, elements):
for element in elements:
element.parent = self
self._children[start:stop] = list(elements)
def append(self, element):
self._children.append(element)
element.parent = self
def insert(self, index, element):
self._children.insert(index, element)
element.parent = self
def __delitem__(self, index):
ob = self._children[index]
ob.parent = None
del self._children[index]
def __delslice__(self, start, stop):
obs = self._children[start:stop]
for ob in obs:
ob.parent = None
del self._children[start:stop]
def remove(self, element):
self._children.remove(element)
element.parent = None
def makeelement(self, tag, attrib):
return self.__class__(tag, attrib)
# meld-specific
def __mod__(self, other):
""" Fill in the text values of meld nodes in tree; only
support dictionarylike operand (sequence operand doesn't seem
to make sense here)"""
return self.fillmelds(**other)
def fillmelds(self, **kw):
""" Fill in the text values of meld nodes in tree using the
keyword arguments passed in; use the keyword keys as meld ids
and the keyword values as text that should fill in the node
text on which that meld id is found. Return a list of keys
from **kw that were not able to be found anywhere in the tree.
Never raises an exception. """
unfilled = []
for k in kw:
node = self.findmeld(k)
if node is None:
unfilled.append(k)
else:
node.text = kw[k]
return unfilled
def fillmeldhtmlform(self, **kw):
""" Perform magic to 'fill in' HTML form element values from a
dictionary. Unlike 'fillmelds', the type of element being
'filled' is taken into consideration.
Perform a 'findmeld' on each key in the dictionary and use the
value that corresponds to the key to perform mutation of the
tree, changing data in what is presumed to be one or more HTML
form elements according to the following rules::
If the found element is an 'input group' (its meld id ends
with the string ':inputgroup'), set the 'checked' attribute
on the appropriate subelement which has a 'value' attribute
which matches the dictionary value. Also remove the
'checked' attribute from every other 'input' subelement of
the input group. If no input subelement's value matches the
dictionary value, this key is treated as 'unfilled'.
If the found element is an 'input type=text', 'input
type=hidden', 'input type=submit', 'input type=password',
'input type=reset' or 'input type=file' element, replace its
'value' attribute with the value.
If the found element is an 'input type=checkbox' or 'input
type='radio' element, set its 'checked' attribute to true if
the dict value is true, or remove its 'checked' attribute if
the dict value is false.
If the found element is a 'select' element and the value
exists in the 'value=' attribute of one of its 'option'
subelements, change that option's 'selected' attribute to
true and mark all other option elements as unselected. If
the select element does not contain an option with a value
that matches the dictionary value, do nothing and return
this key as unfilled.
If the found element is a 'textarea' or any other kind of
element, replace its text with the value.
If the element corresponding to the key is not found,
do nothing and treat the key as 'unfilled'.
Return a list of 'unfilled' keys, representing meld ids
present in the dictionary but not present in the element tree
or meld ids which could not be filled due to the lack of any
matching subelements for 'select' nodes or 'inputgroup' nodes.
"""
unfilled = []
for k in kw:
node = self.findmeld(k)
if node is None:
unfilled.append(k)
continue
val = kw[k]
if k.endswith(':inputgroup'):
# an input group is a list of input type="checkbox" or
# input type="radio" elements that can be treated as a group
# because they attempt to specify the same value
found = []
unfound = []
for child in node.findall('input'):
input_type = child.attrib.get('type', '').lower()
if input_type not in ('checkbox', 'radio'):
continue
input_val = child.attrib.get('value', '')
if val == input_val:
found.append(child)
else:
unfound.append(child)
if not found:
unfilled.append(k)
else:
for option in found:
option.attrib['checked'] = 'checked'
for option in unfound:
try:
del option.attrib['checked']
except KeyError:
pass
else:
tag = node.tag.lower()
if tag == 'input':
input_type = node.attrib.get('type', 'text').lower()
# fill in value attrib for most input types
if input_type in ('hidden', 'submit', 'text',
'password', 'reset', 'file'):
node.attrib['value'] = val
# unless it's a checkbox or radio attribute, then we
# fill in its checked attribute
elif input_type in ('checkbox', 'radio'):
if val:
node.attrib['checked'] = 'checked'
else:
try:
del node.attrib['checked']
except KeyError:
pass
else:
unfilled.append(k)
elif tag == 'select':
# if the node is a select node, we want to select
# the value matching val, otherwise it's unfilled
found = []
unfound = []
for option in node.findall('option'):
if option.attrib.get('value', '') == val:
found.append(option)
else:
unfound.append(option)
if not found:
unfilled.append(k)
else:
for option in found:
option.attrib['selected'] = 'selected'
for option in unfound:
try:
del option.attrib['selected']
except KeyError:
pass
else:
node.text = kw[k]
return unfilled
def findmeld(self, name, default=None):
""" Find a node in the tree that has a 'meld id' corresponding
to 'name'. Iterate over all subnodes recursively looking for a
node which matches. If we can't find the node, return None."""
# this could be faster if we indexed all the meld nodes in the
# tree; we just walk the whole hierarchy now.
result = helper.findmeld(self, name)
if result is None:
return default
return result
def findmelds(self):
""" Find all nodes that have a meld id attribute and return
the found nodes in a list"""
return self.findwithattrib(_MELD_ID)
def findwithattrib(self, attrib, value=None):
""" Find all nodes that have an attribute named 'attrib'. If
'value' is not None, omit nodes on which the attribute value
does not compare equally to 'value'. Return the found nodes in
a list."""
iterator = helper.getiterator(self)
elements = []
for element in iterator:
attribval = element.attrib.get(attrib)
if attribval is not None:
if value is None:
elements.append(element)
else:
if value == attribval:
elements.append(element)
return elements
# ZPT-alike methods
def repeat(self, iterable, childname=None):
"""repeats an element with values from an iterable. If
'childname' is not None, repeat the element on which the
repeat is called, otherwise find the child element with a
'meld:id' matching 'childname' and repeat that. The element
is repeated within its parent element (nodes that are created
as a result of a repeat share the same parent). This method
returns an iterable; the value of each iteration is a
two-sequence in the form (newelement, data). 'newelement' is
a clone of the template element (including clones of its
children) which has already been seated in its parent element
in the template. 'data' is a value from the passed in
iterable. Changing 'newelement' (typically based on values
from 'data') mutates the element 'in place'."""
if childname:
element = self.findmeld(childname)
else:
element = self
parent = element.parent
# creating a list is faster than yielding a generator (py 2.4)
L = []
first = True
for thing in iterable:
if first is True:
clone = element
else:
clone = helper.bfclone(element, parent)
L.append((clone, thing))
first = False
return L
def replace(self, text, structure=False):
""" Replace this element with a Replace node in our parent with
the text 'text' and return the index of our position in
our parent. If we have no parent, do nothing, and return None.
Pass the 'structure' flag to the replace node so it can do the right
thing at render time. """
parent = self.parent
i = self.deparent()
if i is not None:
# reduce function call overhead by not calliing self.insert
node = Replace(text, structure)
parent._children.insert(i, node)
node.parent = parent
return i
def content(self, text, structure=False):
""" Delete this node's children and append a Replace node that
contains text. Always return None. Pass the 'structure' flag
to the replace node so it can do the right thing at render
time."""
helper.content(self, text, structure)
def attributes(self, **kw):
""" Set attributes on this node. """
for k, v in kw.items():
# prevent this from getting to the parser if possible
if not isinstance(k, types.StringTypes):
raise ValueError, 'do not set non-stringtype as key: %s' % k
if not isinstance(v, types.StringTypes):
raise ValueError, 'do not set non-stringtype as val: %s' % v
self.attrib[k] = kw[k]
# output methods
def write_xmlstring(self, encoding=None, doctype=None, fragment=False,
declaration=True, pipeline=False):
data = []
write = data.append
if not fragment:
if declaration:
_write_declaration(write, encoding)
if doctype:
_write_doctype(write, doctype)
_write_xml(write, self, encoding, {}, pipeline)
return ''.join(data)
def write_xml(self, file, encoding=None, doctype=None,
fragment=False, declaration=True, pipeline=False):
""" Write XML to 'file' (which can be a filename or filelike object)
encoding - encoding string (if None, 'utf-8' encoding is assumed)
Must be a recognizable Python encoding type.
doctype - 3-tuple indicating name, pubid, system of doctype.
The default is to prevent a doctype from being emitted.
fragment - True if a 'fragment' should be emitted for this node (no
declaration, no doctype). This causes both the
'declaration' and 'doctype' parameters to become ignored
if provided.
declaration - emit an xml declaration header (including an encoding
if it's not None). The default is to emit the
doctype.
pipeline - preserve 'meld' namespace identifiers in output
for use in pipelining
"""
if not hasattr(file, "write"):
file = open(file, "wb")
data = self.write_xmlstring(encoding, doctype, fragment, declaration,
pipeline)
file.write(data)
def write_htmlstring(self, encoding=None, doctype=doctype.html,
fragment=False):
data = []
write = data.append
if encoding is None:
encoding = 'utf8'
if encoding in ('utf8', 'utf-8', 'latin-1', 'latin1',
'ascii'):
# optimize for common dumb-American case (only encode once at
# the end)
if not fragment:
if doctype:
_write_doctype(write, doctype)
_write_html_no_encoding(write, self, {})
joined = ''.join(data)
return joined
else:
if not fragment:
if doctype:
_write_doctype(write, doctype)
_write_html(write, self, encoding, {})
joined = ''.join(data)
return joined
def write_html(self, file, encoding=None, doctype=doctype.html,
fragment=False):
""" Write HTML to 'file' (which can be a filename or filelike object)
encoding - encoding string (if None, 'utf-8' encoding is assumed).
Unlike XML output, this is not used in a declaration,
but it is used to do actual character encoding during
output. Must be a recognizable Python encoding type.
doctype - 3-tuple indicating name, pubid, system of doctype.
The default is the value of doctype.html (HTML 4.0
'loose')
fragment - True if a "fragment" should be omitted (no doctype).
This overrides any provided "doctype" parameter if
provided.
Namespace'd elements and attributes have their namespaces removed
during output when writing HTML, so pipelining cannot be performed.
HTML is not valid XML, so an XML declaration header is never emitted.
"""
if not hasattr(file, "write"):
file = open(file, "wb")
page = self.write_htmlstring(encoding, doctype, fragment)
file.write(page)
def write_xhtmlstring(self, encoding=None, doctype=doctype.xhtml,
fragment=False, declaration=False, pipeline=False):
data = []
write = data.append
if not fragment:
if declaration:
_write_declaration(write, encoding)
if doctype:
_write_doctype(write, doctype)
_write_xml(write, self, encoding, {}, pipeline, xhtml=True)
return ''.join(data)
def write_xhtml(self, file, encoding=None, doctype=doctype.xhtml,
fragment=False, declaration=False, pipeline=False):
""" Write XHTML to 'file' (which can be a filename or filelike object)
encoding - encoding string (if None, 'utf-8' encoding is assumed)
Must be a recognizable Python encoding type.
doctype - 3-tuple indicating name, pubid, system of doctype.
The default is the value of doctype.xhtml (XHTML
'loose').
fragment - True if a 'fragment' should be emitted for this node (no
declaration, no doctype). This causes both the
'declaration' and 'doctype' parameters to be ignored.
declaration - emit an xml declaration header (including an encoding
string if 'encoding' is not None)
pipeline - preserve 'meld' namespace identifiers in output
for use in pipelining
"""
# use a list as a collector, and only call the write method of
# the file once we've collected all output (reduce function call
# overhead)
data = []
write = data.append
if not hasattr(file, "write"):
file = open(file, "wb")
page = self.write_xhtmlstring(encoding, doctype, fragment, declaration,
pipeline)
file.write(page)
def clone(self, parent=None):
""" Create a clone of an element. If parent is not None,
append the element to the parent. Recurse as necessary to create
a deep clone of the element. """
return helper.bfclone(self, parent)
def deparent(self):
""" Remove ourselves from our parent node (de-parent) and return
the index of the parent which was deleted. """
i = self.parentindex()
if i is not None:
del self.parent[i]
return i
def parentindex(self):
""" Return the parent node index in which we live """
parent = self.parent
if parent is not None:
return parent._children.index(self)
def shortrepr(self, encoding=None):
data = []
_write_html(data.append, self, encoding, {}, maxdepth=2)
return ''.join(data)
def diffmeld(self, other):
""" Compute the meld element differences from this node (the
source) to 'other' (the target). Return a dictionary of
sequences in the form {'unreduced:
{'added':[], 'removed':[], 'moved':[]},
'reduced':
{'added':[], 'removed':[], 'moved':[]},}
"""
srcelements = self.findmelds()
tgtelements = other.findmelds()
srcids = [ x.meldid() for x in srcelements ]
tgtids = [ x.meldid() for x in tgtelements ]
removed = []
for srcelement in srcelements:
if srcelement.meldid() not in tgtids:
removed.append(srcelement)
added = []
for tgtelement in tgtelements:
if tgtelement.meldid() not in srcids:
added.append(tgtelement)
moved = []
for srcelement in srcelements:
srcid = srcelement.meldid()
if srcid in tgtids:
i = tgtids.index(srcid)
tgtelement = tgtelements[i]
if not sharedlineage(srcelement, tgtelement):
moved.append(tgtelement)
unreduced = {'added':added, 'removed':removed, 'moved':moved}
moved_reduced = diffreduce(moved)
added_reduced = diffreduce(added)
removed_reduced = diffreduce(removed)
reduced = {'moved':moved_reduced, 'added':added_reduced,
'removed':removed_reduced}
return {'unreduced':unreduced,
'reduced':reduced}
def meldid(self):
return self.attrib.get(_MELD_ID)
def lineage(self):
L = []
parent = self
while parent is not None:
L.append(parent)
parent = parent.parent
return L
def MeldTreeBuilder():
return TreeBuilder(element_factory=_MeldElementInterface)
class MeldParser(XMLTreeBuilder):
""" A parser based on Fredrik's PIParser at
http://effbot.org/zone/element-pi.htm. It blithely ignores the
case of a comment existing outside the root element and ignores
processing instructions entirely. We need to validate that there
are no repeated meld id's in the source as well """
def __init__(self, html=0, target=None):
XMLTreeBuilder.__init__(self, html, target)
# assumes ElementTree 1.2.X
self._parser.CommentHandler = self.handle_comment
self.meldids = {}
def handle_comment(self, data):
self._target.start(Comment, {})
self._target.data(data)
self._target.end(Comment)
def _start(self, tag, attrib_in):
# this is used by self._parser (an Expat parser) as
# StartElementHandler but only if _start_list is not
# provided... so why does this method exist?
for key in attrib_in:
if '{' + key == _MELD_ID:
meldid = attrib_in[key]
if self.meldids.get(meldid):
raise ValueError, ('Repeated meld id "%s" in source' %
meldid)
self.meldids[meldid] = 1
return XMLTreeBuilder._start(self, tag, attrib_in)
def _start_list(self, tag, attrib_in):
# This is used by self._parser (an Expat parser)
# as StartElementHandler. attrib_in is a flat even-length
# sequence of name, value pairs for all attributes.
# See http://python.org/doc/lib/xmlparser-objects.html
for i in range(0, len(attrib_in), 2):
# For some reason, clark names are missing the leading '{'
attrib = self._fixname(attrib_in[i])
if _MELD_ID == attrib:
meldid = attrib_in[i+1]
if self.meldids.get(meldid):
raise ValueError, ('Repeated meld id "%s" in source' %
meldid)
self.meldids[meldid] = 1
return XMLTreeBuilder._start_list(self, tag, attrib_in)
def close(self):
val = XMLTreeBuilder.close(self)
self.meldids = {}
return val
class HTMLMeldParser(HTMLParser):
""" A mostly-cut-and-paste of ElementTree's HTMLTreeBuilder that
does special meld3 things (like preserve comments and munge meld
ids). Subclassing is not possible due to private attributes. :-("""
def __init__(self, builder=None, encoding=None):
self.__stack = []
if builder is None:
builder = MeldTreeBuilder()
self.builder = builder
self.encoding = encoding or "iso-8859-1"
HTMLParser.__init__(self)
self.meldids = {}
def close(self):
HTMLParser.close(self)
self.meldids = {}
return self.builder.close()
def handle_starttag(self, tag, attrs):
if tag == "meta":
# look for encoding directives
http_equiv = content = None
for k, v in attrs:
if k == "http-equiv":
http_equiv = v.lower()
elif k == "content":
content = v
if http_equiv == "content-type" and content:
# use mimetools to parse the http header
header = mimetools.Message(
StringIO("%s: %s\n\n" % (http_equiv, content))
)
encoding = header.getparam("charset")
if encoding:
self.encoding = encoding
if tag in AUTOCLOSE:
if self.__stack and self.__stack[-1] == tag:
self.handle_endtag(tag)
self.__stack.append(tag)
attrib = {}
if attrs:
for k, v in attrs:
if k == _MELD_SHORT_ID:
k = _MELD_ID
if self.meldids.get(v):
raise ValueError, ('Repeated meld id "%s" in source' %
v)
self.meldids[v] = 1
else:
k = k.lower()
attrib[k] = v
self.builder.start(tag, attrib)
if tag in IGNOREEND:
self.__stack.pop()
self.builder.end(tag)
def handle_endtag(self, tag):
if tag in IGNOREEND:
return
lasttag = self.__stack.pop()
if tag != lasttag and lasttag in AUTOCLOSE:
self.handle_endtag(lasttag)
self.builder.end(tag)
def handle_charref(self, char):
if char[:1] == "x":
char = int(char[1:], 16)
else:
char = int(char)
if 0 <= char < 128:
self.builder.data(chr(char))
else:
self.builder.data(unichr(char))
def handle_entityref(self, name):
entity = htmlentitydefs.entitydefs.get(name)
if entity:
if len(entity) == 1:
entity = ord(entity)
else:
entity = int(entity[2:-1])
if 0 <= entity < 128:
self.builder.data(chr(entity))
else:
self.builder.data(unichr(entity))
else:
self.unknown_entityref(name)
def handle_data(self, data):
if isinstance(data, type('')) and is_not_ascii(data):
# convert to unicode, but only if necessary
data = unicode(data, self.encoding, "ignore")
self.builder.data(data)
def unknown_entityref(self, name):
pass # ignore by default; override if necessary
def handle_comment(self, data):
self.builder.start(Comment, {})
self.builder.data(data)
self.builder.end(Comment)
def do_parse(source, parser):
root = et_parse(source, parser=parser).getroot()
iterator = root.getiterator()
for p in iterator:
for c in p:
c.parent = p
return root
def parse_xml(source):
""" Parse source (a filelike object) into an element tree. If
html is true, use a parser that can resolve somewhat ambiguous
HTML into XHTML. Otherwise use a 'normal' parser only."""
builder = MeldTreeBuilder()
parser = MeldParser(target=builder)
return do_parse(source, parser)
def parse_html(source, encoding=None):
builder = MeldTreeBuilder()
parser = HTMLMeldParser(builder, encoding)
return do_parse(source, parser)
def parse_xmlstring(text):
source = StringIO(text)
return parse_xml(source)
def parse_htmlstring(text, encoding=None):
source = StringIO(text)
return parse_html(source, encoding)
attrib_needs_escaping = re.compile(r'[&"<]').search
cdata_needs_escaping = re.compile(r'[&<]').search
def _both_case(mapping):
# Add equivalent upper-case keys to mapping.
lc_keys = mapping.keys()
for k in lc_keys:
mapping[k.upper()] = mapping[k]
_HTMLTAGS_UNBALANCED = {'area':1, 'base':1, 'basefont':1, 'br':1, 'col':1,
'frame':1, 'hr':1, 'img':1, 'input':1, 'isindex':1,
'link':1, 'meta':1, 'param':1}
_both_case(_HTMLTAGS_UNBALANCED)
_HTMLTAGS_NOESCAPE = {'script':1, 'style':1}
_both_case(_HTMLTAGS_NOESCAPE)
_HTMLATTRS_BOOLEAN = {'selected':1, 'checked':1, 'compact':1, 'declare':1,
'defer':1, 'disabled':1, 'ismap':1, 'multiple':1,
'nohref':1, 'noresize':1, 'noshade':1, 'nowrap':1}
_both_case(_HTMLATTRS_BOOLEAN)
def _write_html(write, node, encoding, namespaces, depth=-1, maxdepth=None):
" Write HTML to file """
if encoding is None:
encoding = 'utf-8'
tag = node.tag
tail = node.tail
text = node.text
tail = node.tail
to_write = ""
if tag is Replace:
if not node.structure:
if cdata_needs_escaping(text):
text = _escape_cdata(text)
write(text.encode(encoding))
elif tag is Comment:
if cdata_needs_escaping(text):
text = _escape_cdata(text)
write('<!-- ' + text + ' -->'.encode(encoding))
elif tag is ProcessingInstruction:
if cdata_needs_escaping(text):
text = _escape_cdata(text)
write('<!-- ' + text + ' -->'.encode(encoding))
else:
xmlns_items = [] # new namespaces in this scope
try:
if tag[:1] == "{":
if tag[:_XHTML_PREFIX_LEN] == _XHTML_PREFIX:
tag = tag[_XHTML_PREFIX_LEN:]
else:
tag, xmlns = fixtag(tag, namespaces)
if xmlns:
xmlns_items.append(xmlns)
except TypeError:
_raise_serialization_error(tag)
to_write += "<%s" % tag.encode(encoding)
attrib = node.attrib
if attrib is not None:
if len(attrib) > 1:
attrib_keys = attrib.keys()
attrib_keys.sort()
else:
attrib_keys = attrib
for k in attrib_keys:
try:
if k[:1] == "{":
continue
except TypeError:
_raise_serialization_error(k)
if k in _HTMLATTRS_BOOLEAN:
to_write += ' ' + k.encode(encoding)
else:
v = attrib[k]
to_write += " %s=\"%s\"" % (k, v)
for k, v in xmlns_items:
to_write += " %s=\"%s\"" % (k, v)
to_write += ">"
if text is not None and text:
if tag in _HTMLTAGS_NOESCAPE:
to_write += text.encode(encoding)
elif cdata_needs_escaping(text):
to_write += _escape_cdata(text)
else:
to_write += text.encode(encoding)
write(to_write)
for child in node._children:
if maxdepth is not None:
depth = depth + 1
if depth < maxdepth:
_write_html(write, child, encoding, namespaces, depth,
maxdepth)
elif depth == maxdepth and text:
write(' [...]\n')
else:
_write_html(write, child, encoding, namespaces, depth, maxdepth)
if text or node._children or tag not in _HTMLTAGS_UNBALANCED:
write("</" + tag.encode(encoding) + ">")
if tail:
if cdata_needs_escaping(tail):
write(_escape_cdata(tail))
else:
write(tail.encode(encoding))
def _write_html_no_encoding(write, node, namespaces):
""" Append HTML to string without any particular unicode encoding.
We have a separate function for this due to the fact that encoding
while recursing is very expensive if this will get serialized out to
utf8 anyway (the encoding can happen afterwards). We append to a string
because it's faster than calling any 'write' or 'append' function."""
tag = node.tag
tail = node.tail
text = node.text
tail = node.tail
to_write = ""
if tag is Replace:
if not node.structure:
if cdata_needs_escaping(text):
text = _escape_cdata_noencoding(text)
write(text)
elif tag is Comment:
if cdata_needs_escaping(text):
text = _escape_cdata_noencoding(text)
write('<!-- ' + text + ' -->')
elif tag is ProcessingInstruction:
if cdata_needs_escaping(text):
text = _escape_cdata_noencoding(text)
write('<!-- ' + text + ' -->')
else:
xmlns_items = [] # new namespaces in this scope
try:
if tag[:1] == "{":
if tag[:_XHTML_PREFIX_LEN] == _XHTML_PREFIX:
tag = tag[_XHTML_PREFIX_LEN:]
else:
tag, xmlns = fixtag(tag, namespaces)
if xmlns:
xmlns_items.append(xmlns)
except TypeError:
_raise_serialization_error(tag)
to_write += "<" + tag
attrib = node.attrib
if attrib is not None:
if len(attrib) > 1:
attrib_keys = attrib.keys()
attrib_keys.sort()
else:
attrib_keys = attrib
for k in attrib_keys:
try:
if k[:1] == "{":
continue
except TypeError:
_raise_serialization_error(k)
if k in _HTMLATTRS_BOOLEAN:
to_write += ' ' + k
else:
v = attrib[k]
to_write += " %s=\"%s\"" % (k, v)
for k, v in xmlns_items:
to_write += " %s=\"%s\"" % (k, v)
to_write += ">"
if text is not None and text:
if tag in _HTMLTAGS_NOESCAPE:
to_write += text
elif cdata_needs_escaping(text):
to_write += _escape_cdata_noencoding(text)
else:
to_write += text
write(to_write)
for child in node._children:
_write_html_no_encoding(write, child, namespaces)
if text or node._children or tag not in _HTMLTAGS_UNBALANCED:
write("</" + tag + ">")
if tail:
if cdata_needs_escaping(tail):
write(_escape_cdata_noencoding(tail))
else:
write(tail)
def _write_xml(write, node, encoding, namespaces, pipeline, xhtml=False):
""" Write XML to a file """
if encoding is None:
encoding = 'utf-8'
tag = node.tag
if tag is Comment:
write("<!-- %s -->" % _escape_cdata(node.text, encoding))
elif tag is ProcessingInstruction:
write("<?%s?>" % _escape_cdata(node.text, encoding))
elif tag is Replace:
if node.structure:
# this may produce invalid xml
write(node.text.encode(encoding))
else:
write(_escape_cdata(node.text, encoding))
else:
if xhtml:
if tag[:_XHTML_PREFIX_LEN] == _XHTML_PREFIX:
tag = tag[_XHTML_PREFIX_LEN:]
if node.attrib:
items = node.attrib.items()
else:
items = [] # must always be sortable.
xmlns_items = [] # new namespaces in this scope
try:
if tag[:1] == "{":
tag, xmlns = fixtag(tag, namespaces)
if xmlns:
xmlns_items.append(xmlns)
except TypeError:
_raise_serialization_error(tag)
write("<" + tag.encode(encoding))
if items or xmlns_items:
items.sort() # lexical order
for k, v in items:
try:
if k[:1] == "{":
if not pipeline:
if k == _MELD_ID:
continue
k, xmlns = fixtag(k, namespaces)
if xmlns: xmlns_items.append(xmlns)
if not pipeline:
# special-case for HTML input
if k == 'xmlns:meld':
continue
except TypeError:
_raise_serialization_error(k)
write(" %s=\"%s\"" % (k.encode(encoding),
_escape_attrib(v, encoding)))
for k, v in xmlns_items:
write(" %s=\"%s\"" % (k.encode(encoding),
_escape_attrib(v, encoding)))
if node.text or node._children:
write(">")
if node.text:
write(_escape_cdata(node.text, encoding))
for n in node._children:
_write_xml(write, n, encoding, namespaces, pipeline, xhtml)
write("</" + tag.encode(encoding) + ">")
else:
write(" />")
for k, v in xmlns_items:
del namespaces[v]
if node.tail:
write(_escape_cdata(node.tail, encoding))
# overrides to elementtree to increase speed and get entity quoting correct.
nonentity_re = re.compile('&(?!([#\w]*;))') # negative lookahead assertion
def _escape_cdata(text, encoding=None):
# escape character data
try:
if encoding:
try:
text = text.encode(encoding)
except UnicodeError:
return _encode_entity(text)
text = nonentity_re.sub('&', text)
text = text.replace("<", "<")
return text
except (TypeError, AttributeError):
_raise_serialization_error(text)
def _escape_attrib(text, encoding=None):
# escape attribute value
try:
if encoding:
try:
text = text.encode(encoding)
except UnicodeError:
return _encode_entity(text)
# don't requote properly-quoted entities
text = nonentity_re.sub('&', text)
text = text.replace("<", "<")
text = text.replace('"', """)
return text
except (TypeError, AttributeError):
_raise_serialization_error(text)
def _escape_cdata_noencoding(text):
# escape character data
text = nonentity_re.sub('&', text)
text = text.replace("<", "<")
return text
def _escape_attrib_noencoding(text):
# don't requote properly-quoted entities
text = nonentity_re.sub('&', text)
text = text.replace("<", "<")
text = text.replace('"', """)
return text
# utility functions
def _write_declaration(write, encoding):
if not encoding:
write('<?xml version="1.0"?>\n')
else:
write('<?xml version="1.0" encoding="%s"?>\n' % encoding)
def _write_doctype(write, doctype):
try:
name, pubid, system = doctype
except (ValueError, TypeError):
raise ValueError, ("doctype must be supplied as a 3-tuple in the form "
"(name, pubid, system) e.g. '%s'" % doctype.xhtml)
write('<!DOCTYPE %s PUBLIC "%s" "%s">\n' % (name, pubid, system))
xml_decl_re = re.compile(r'<\?xml .*?\?>')
begin_tag_re = re.compile(r'<[^/?!]?\w+')
'<!DOCTYPE %s PUBLIC "%s" "%s">' % doctype.html
def insert_doctype(data, doctype=doctype.xhtml):
# jam an html doctype declaration into 'data' if it
# doesn't already contain a doctype declaration
match = xml_decl_re.search(data)
dt_string = '<!DOCTYPE %s PUBLIC "%s" "%s">' % doctype
if match is not None:
start, end = match.span(0)
before = data[:start]
tag = data[start:end]
after = data[end:]
return before + tag + dt_string + after
else:
return dt_string + data
def insert_meld_ns_decl(data):
match = begin_tag_re.search(data)
if match is not None:
start, end = match.span(0)
before = data[:start]
tag = data[start:end] + ' xmlns:meld="%s"' % _MELD_NS_URL
after = data[end:]
data = before + tag + after
return data
def prefeed(data, doctype=doctype.xhtml):
if data.find('<!DOCTYPE') == -1:
data = insert_doctype(data, doctype)
if data.find('xmlns:meld') == -1:
data = insert_meld_ns_decl(data)
return data
def sharedlineage(srcelement, tgtelement):
srcparent = srcelement.parent
tgtparent = tgtelement.parent
srcparenttag = getattr(srcparent, 'tag', None)
tgtparenttag = getattr(tgtparent, 'tag', None)
if srcparenttag != tgtparenttag:
return False
elif tgtparenttag is None and srcparenttag is None:
return True
elif tgtparent and srcparent:
return sharedlineage(srcparent, tgtparent)
return False
def diffreduce(elements):
# each element in 'elements' should all have non-None meldids, and should
# be preordered in depth-first traversal order
reduced = []
for element in elements:
parent = element.parent
if parent is None:
reduced.append(element)
continue
if parent in reduced:
continue
reduced.append(element)
return reduced
def intersection(S1, S2):
L = []
for element in S1:
if element in S2:
L.append(element)
return L
def melditerator(element, meldid=None, _MELD_ID=_MELD_ID):
nodeid = element.attrib.get(_MELD_ID)
if nodeid is not None:
if meldid is None or nodeid == meldid:
yield element
for child in element._children:
for el2 in melditerator(child, meldid):
nodeid = el2.attrib.get(_MELD_ID)
if nodeid is not None:
if meldid is None or nodeid == meldid:
yield el2
def search(name):
if not "." in name:
raise ValueError("unloadable datatype name: " + `name`)
components = name.split('.')
start = components[0]
g = globals()
package = __import__(start, g, g)
modulenames = [start]
for component in components[1:]:
modulenames.append(component)
try:
package = getattr(package, component)
except AttributeError:
n = '.'.join(modulenames)
package = __import__(n, g, g, component)
return package
def sample_mutator(root):
values = []
for thing in range(0, 20):
values.append((str(thing), str(thing)))
ob = root.findmeld('tr')
for tr, (name, desc) in ob.repeat(values):
tr.findmeld('td1').content(name)
tr.findmeld('td2').content(desc)
if __name__ == '__main__':
# call interactively by invoking meld3.py with a filename and
# a dotted-python-path name to a mutator function that accepts a single
# argument (the root), e.g.:
#
# python meld3.py sample.html meld3.sample_mutator
#
# the rendering will be sent to stdout
import sys
filename = sys.argv[1]
try:
mutator = sys.argv[2]
except IndexError:
mutator = None
import timeit
root = parse_html(open(filename, 'r'))
io = StringIO()
if mutator:
mutator = search(mutator)
mutator(root)
root.write_html(io)
sys.stdout.write(io.getvalue())
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