def parse_with(self):
node = nodes.With(lineno=next(self.stream).lineno)
targets = []
values = []
while self.stream.current.type != 'block_end':
lineno = self.stream.current.lineno
if targets:
self.stream.expect('comma')
target = self.parse_assign_target()
target.set_ctx('param')
targets.append(target)
self.stream.expect('assign')
values.append(self.parse_expression())
node.targets = targets
node.values = values
node.body = self.parse_statements(('name:endwith', ), drop_needle=True)
return node
def parse(self, parser):
# Create a normal With node first
# Borrowing the codes from parser.py,
# the only difference is the end tag is `endrequired`
# instead of `endwith`
with_node = nodes.With(lineno=next(parser.stream).lineno)
targets = []
values = []
while parser.stream.current.type != 'block_end':
if targets:
parser.stream.expect('comma')
target = parser.parse_assign_target()
target.set_ctx('param')
targets.append(target)
parser.stream.expect('assign')
values.append(parser.parse_expression())
with_node.targets = targets
with_node.values = values
with_node.body = parser.parse_statements(('name:endrequired', ),
drop_needle=True)
# Manually create a If node
if_node = nodes.If()
# If only one variable is required, assigned that variable to test if it is empty
if len(values) == 1:
test = values[0]
else:
# If more than one variables are required, concat them into a And node
test = nodes.And(left=values[0], right=values[1])
for i in range(2, len(values)):
test = nodes.And(left=test, right=values[i])
if_node.test = test
# Assign with_node as the body of the if_node, to nest them
if_node.body = [with_node]
# set other fields to empty list.
for _f in nodes.If:
if getattr(if_node, _f) is None:
setattr(if_node, _f, [])
return if_node
