mirror of
https://github.com/ytdl-org/youtube-dl
synced 2024-12-22 04:00:09 +09:00
[compat] Improve compat_etree_iterfind for Py2.6
Adapted from https://raw.githubusercontent.com/python/cpython/2.7/Lib/xml/etree/ElementPath.py
This commit is contained in:
dirkf
parent
06da64ee51
commit
34484e49f5
@ -2720,9 +2720,217 @@ if sys.version_info < (2, 7):
|
||||
xpath = xpath.encode('ascii')
|
||||
return xpath
|
||||
|
||||
def compat_etree_iterfind(element, match):
|
||||
for from_ in element.findall(match):
|
||||
yield from_
|
||||
# further code below based on CPython 2.7 source
|
||||
import functools
|
||||
|
||||
_xpath_tokenizer_re = re.compile(r'''(?x)
|
||||
( # (1)
|
||||
'[^']*'|"[^"]*"| # quoted strings, or
|
||||
::|//?|\.\.|\(\)|[/.*:[\]()@=] # navigation specials
|
||||
)| # or (2)
|
||||
((?:\{[^}]+\})?[^/[\]()@=\s]+)| # token: optional {ns}, no specials
|
||||
\s+ # or white space
|
||||
''')
|
||||
|
||||
def _xpath_tokenizer(pattern, namespaces=None):
|
||||
for token in _xpath_tokenizer_re.findall(pattern):
|
||||
tag = token[1]
|
||||
if tag and tag[0] != "{" and ":" in tag:
|
||||
try:
|
||||
if not namespaces:
|
||||
raise KeyError
|
||||
prefix, uri = tag.split(":", 1)
|
||||
yield token[0], "{%s}%s" % (namespaces[prefix], uri)
|
||||
except KeyError:
|
||||
raise SyntaxError("prefix %r not found in prefix map" % prefix)
|
||||
else:
|
||||
yield token
|
||||
|
||||
def _get_parent_map(context):
|
||||
parent_map = context.parent_map
|
||||
if parent_map is None:
|
||||
context.parent_map = parent_map = {}
|
||||
for p in context.root.getiterator():
|
||||
for e in p:
|
||||
parent_map[e] = p
|
||||
return parent_map
|
||||
|
||||
def _select(context, result, filter_fn=lambda *_: True):
|
||||
for elem in result:
|
||||
for e in elem:
|
||||
if filter_fn(e, elem):
|
||||
yield e
|
||||
|
||||
def _prepare_child(next_, token):
|
||||
tag = token[1]
|
||||
return functools.partial(_select, filter_fn=lambda e, _: e.tag == tag)
|
||||
|
||||
def _prepare_star(next_, token):
|
||||
return _select
|
||||
|
||||
def _prepare_self(next_, token):
|
||||
return lambda _, result: (e for e in result)
|
||||
|
||||
def _prepare_descendant(next_, token):
|
||||
token = next(next_)
|
||||
if token[0] == "*":
|
||||
tag = "*"
|
||||
elif not token[0]:
|
||||
tag = token[1]
|
||||
else:
|
||||
raise SyntaxError("invalid descendant")
|
||||
|
||||
def select(context, result):
|
||||
for elem in result:
|
||||
for e in elem.getiterator(tag):
|
||||
if e is not elem:
|
||||
yield e
|
||||
return select
|
||||
|
||||
def _prepare_parent(next_, token):
|
||||
def select(context, result):
|
||||
# FIXME: raise error if .. is applied at toplevel?
|
||||
parent_map = _get_parent_map(context)
|
||||
result_map = {}
|
||||
for elem in result:
|
||||
if elem in parent_map:
|
||||
parent = parent_map[elem]
|
||||
if parent not in result_map:
|
||||
result_map[parent] = None
|
||||
yield parent
|
||||
return select
|
||||
|
||||
def _prepare_predicate(next_, token):
|
||||
signature = []
|
||||
predicate = []
|
||||
for token in next_:
|
||||
if token[0] == "]":
|
||||
break
|
||||
if token[0] and token[0][:1] in "'\"":
|
||||
token = "'", token[0][1:-1]
|
||||
signature.append(token[0] or "-")
|
||||
predicate.append(token[1])
|
||||
|
||||
def select(context, result, filter_fn=lambda _: True):
|
||||
for elem in result:
|
||||
if filter_fn(elem):
|
||||
yield elem
|
||||
|
||||
signature = "".join(signature)
|
||||
# use signature to determine predicate type
|
||||
if signature == "@-":
|
||||
# [@attribute] predicate
|
||||
key = predicate[1]
|
||||
return functools.partial(
|
||||
select, filter_fn=lambda el: el.get(key) is not None)
|
||||
if signature == "@-='":
|
||||
# [@attribute='value']
|
||||
key = predicate[1]
|
||||
value = predicate[-1]
|
||||
return functools.partial(
|
||||
select, filter_fn=lambda el: el.get(key) == value)
|
||||
if signature == "-" and not re.match(r"\d+$", predicate[0]):
|
||||
# [tag]
|
||||
tag = predicate[0]
|
||||
return functools.partial(
|
||||
select, filter_fn=lambda el: el.find(tag) is not None)
|
||||
if signature == "-='" and not re.match(r"\d+$", predicate[0]):
|
||||
# [tag='value']
|
||||
tag = predicate[0]
|
||||
value = predicate[-1]
|
||||
|
||||
def itertext(el):
|
||||
for e in el.getiterator():
|
||||
e = e.text
|
||||
if e:
|
||||
yield e
|
||||
|
||||
def select(context, result):
|
||||
for elem in result:
|
||||
for e in elem.findall(tag):
|
||||
if "".join(itertext(e)) == value:
|
||||
yield elem
|
||||
break
|
||||
return select
|
||||
if signature == "-" or signature == "-()" or signature == "-()-":
|
||||
# [index] or [last()] or [last()-index]
|
||||
if signature == "-":
|
||||
index = int(predicate[0]) - 1
|
||||
else:
|
||||
if predicate[0] != "last":
|
||||
raise SyntaxError("unsupported function")
|
||||
if signature == "-()-":
|
||||
try:
|
||||
index = int(predicate[2]) - 1
|
||||
except ValueError:
|
||||
raise SyntaxError("unsupported expression")
|
||||
else:
|
||||
index = -1
|
||||
|
||||
def select(context, result):
|
||||
parent_map = _get_parent_map(context)
|
||||
for elem in result:
|
||||
try:
|
||||
parent = parent_map[elem]
|
||||
# FIXME: what if the selector is "*" ?
|
||||
elems = list(parent.findall(elem.tag))
|
||||
if elems[index] is elem:
|
||||
yield elem
|
||||
except (IndexError, KeyError):
|
||||
pass
|
||||
return select
|
||||
raise SyntaxError("invalid predicate")
|
||||
|
||||
ops = {
|
||||
"": _prepare_child,
|
||||
"*": _prepare_star,
|
||||
".": _prepare_self,
|
||||
"..": _prepare_parent,
|
||||
"//": _prepare_descendant,
|
||||
"[": _prepare_predicate,
|
||||
}
|
||||
|
||||
_cache = {}
|
||||
|
||||
class _SelectorContext:
|
||||
parent_map = None
|
||||
|
||||
def __init__(self, root):
|
||||
self.root = root
|
||||
|
||||
##
|
||||
# Generate all matching objects.
|
||||
|
||||
def compat_etree_iterfind(elem, path, namespaces=None):
|
||||
# compile selector pattern
|
||||
if path[-1:] == "/":
|
||||
path = path + "*" # implicit all (FIXME: keep this?)
|
||||
try:
|
||||
selector = _cache[path]
|
||||
except KeyError:
|
||||
if len(_cache) > 100:
|
||||
_cache.clear()
|
||||
if path[:1] == "/":
|
||||
raise SyntaxError("cannot use absolute path on element")
|
||||
tokens = _xpath_tokenizer(path, namespaces)
|
||||
selector = []
|
||||
for token in tokens:
|
||||
if token[0] == "/":
|
||||
continue
|
||||
try:
|
||||
selector.append(ops[token[0]](tokens, token))
|
||||
except StopIteration:
|
||||
raise SyntaxError("invalid path")
|
||||
_cache[path] = selector
|
||||
# execute selector pattern
|
||||
result = [elem]
|
||||
context = _SelectorContext(elem)
|
||||
for select in selector:
|
||||
result = select(context, result)
|
||||
return result
|
||||
|
||||
# end of code based on CPython 2.7 source
|
||||
|
||||
|
||||
else:
|
||||
compat_xpath = lambda xpath: xpath
|
||||
|
||||
Loading…
Reference in New Issue
Block a user