def top_level_mode(self):
primitive = self.consume_next_primitive()
if isinstance(primitive, Primitive):
if primitive.primitive[0] == "identifier":
self.current_selector = ElementSelector(primitive.primitive[1])
self.mode = ELEMENT_MODE
elif primitive.primitive == ("delim", "*"):
self.current_selector = ElementSelector()
self.mode = ELEMENT_MODE
else:
assert False
elif isinstance(primitive, SimpleBlock):
if primitive.associated_token == ("[",):
self.reprocess_current_primitive()
self.mode = ATTRIBUTE_MODE
else:
assert False
else:
assert False
def attribute_mode(self):
block = self.consume_next_primitive()
if len(block.value) == 1:
if block.value[0].primitive[0] == "identifier":
if self.current_selector:
attr_selector = AttributeSelector(block.value[0].primitive[1])
self.current_selector.append(attr_selector)
else:
self.current_selector = AttributeSelector(block.value[0].primitive[1])
else:
assert False
elif len(block.value) == 3:
if (
block.value[0].primitive[0] == "identifier" and
block.value[1].primitive[0] == "delim" and
block.value[2].primitive[0] == "string"
):
attr_selector = AttributeSelector(
block.value[0].primitive[1],
block.value[2].primitive[1],
block.value[1].primitive[1])
self.current_selector.append(attr_selector)
else:
assert False
elif len(block.value) == 4:
if (
block.value[0].primitive[0] == "identifier" and
block.value[1].primitive[0] == "delim" and
block.value[2].primitive[0] == "delim" and
block.value[3].primitive[0] == "string"
):
attr_selector = AttributeSelector(
block.value[0].primitive[1],
block.value[3].primitive[1],
block.value[1].primitive[1] + block.value[2].primitive[1])
self.current_selector.append(attr_selector)
else:
assert False
else:
assert False
class Selector:
def __init__(self, s):
p = Parser(list(Tokenizer(s + "{}").tokenize()))
p.parse()
self.primitives = p.open_rule_stack[0].value[0].selector
self.index = 0
self.mode = TOP_LEVEL_MODE
self.current_selector = None
def consume_next_primitive(self):
primitive = self.primitives[self.index]
self.index += 1
if isinstance(primitive, Primitive) and primitive.primitive[0] == "whitespace":
return self.consume_next_primitive()
return primitive
def reprocess_current_primitive(self):
self.index -= 1
def parse(self):
while self.index < len(self.primitives):
if self.mode == TOP_LEVEL_MODE:
self.top_level_mode()
elif self.mode == ELEMENT_MODE:
self.element_mode()
elif self.mode == ATTRIBUTE_MODE:
self.attribute_mode()
elif self.mode == CHILD_MODE:
self.child_mode()
elif self.mode == FOLLOWED_BY_MODE:
self.followed_by_mode()
else:
print "UNKNOWN MODE", self.mode
quit()
return self.current_selector
def top_level_mode(self):
primitive = self.consume_next_primitive()
if isinstance(primitive, Primitive):
if primitive.primitive[0] == "identifier":
self.current_selector = ElementSelector(primitive.primitive[1])
self.mode = ELEMENT_MODE
elif primitive.primitive == ("delim", "*"):
self.current_selector = ElementSelector()
self.mode = ELEMENT_MODE
else:
assert False
elif isinstance(primitive, SimpleBlock):
if primitive.associated_token == ("[",):
self.reprocess_current_primitive()
self.mode = ATTRIBUTE_MODE
else:
assert False
else:
assert False
def element_mode(self):
primitive = self.consume_next_primitive()
if isinstance(primitive, SimpleBlock):
if primitive.associated_token == ("[",):
self.reprocess_current_primitive()
self.mode = ATTRIBUTE_MODE
else:
assert False
elif isinstance(primitive, Primitive):
if primitive.primitive[0] == "identifier":
self.current_selector = self.current_selector.descendant(ElementSelector(primitive.primitive[1]))
elif primitive.primitive == ("delim", ">"):
self.mode = CHILD_MODE
elif primitive.primitive == ("delim", "*"):
self.current_selector = self.current_selector.descendant(ElementSelector())
elif primitive.primitive == ("delim", "+"):
self.mode = FOLLOWED_BY_MODE
else:
assert False
else:
assert False
def child_mode(self):
primitive = self.consume_next_primitive()
if isinstance(primitive, Primitive) and primitive.primitive[0] == "identifier":
self.current_selector = self.current_selector.child(ElementSelector(primitive.primitive[1]))
else:
assert False
def followed_by_mode(self):
primitive = self.consume_next_primitive()
if isinstance(primitive, Primitive) and primitive.primitive[0] == "identifier":
self.current_selector = self.current_selector.followed_by(ElementSelector(primitive.primitive[1]))
else:
assert False
def attribute_mode(self):
block = self.consume_next_primitive()
if len(block.value) == 1:
if block.value[0].primitive[0] == "identifier":
if self.current_selector:
attr_selector = AttributeSelector(block.value[0].primitive[1])
self.current_selector.append(attr_selector)
else:
self.current_selector = AttributeSelector(block.value[0].primitive[1])
else:
assert False
elif len(block.value) == 3:
if (
block.value[0].primitive[0] == "identifier" and
block.value[1].primitive[0] == "delim" and
block.value[2].primitive[0] == "string"
):
attr_selector = AttributeSelector(
block.value[0].primitive[1],
block.value[2].primitive[1],
block.value[1].primitive[1])
self.current_selector.append(attr_selector)
else:
assert False
elif len(block.value) == 4:
if (
block.value[0].primitive[0] == "identifier" and
block.value[1].primitive[0] == "delim" and
block.value[2].primitive[0] == "delim" and
block.value[3].primitive[0] == "string"
):
attr_selector = AttributeSelector(
block.value[0].primitive[1],
block.value[3].primitive[1],
block.value[1].primitive[1] + block.value[2].primitive[1])
self.current_selector.append(attr_selector)
else:
assert False
else:
assert False
