parser.py 文件源码

def subparse(self, end_tokens=None):
        body = []
        data_buffer = []
        add_data = data_buffer.append

        if end_tokens is not None:
            self._end_token_stack.append(end_tokens)

        def flush_data():
            if data_buffer:
                lineno = data_buffer[0].lineno
                body.append(nodes.Output(data_buffer[:], lineno=lineno))
                del data_buffer[:]

        try:
            while self.stream:
                token = self.stream.current
                if token.type == 'data':
                    if token.value:
                        add_data(nodes.TemplateData(token.value,
                                                    lineno=token.lineno))
                    next(self.stream)
                elif token.type == 'variable_begin':
                    next(self.stream)
                    add_data(self.parse_tuple(with_condexpr=True))
                    self.stream.expect('variable_end')
                elif token.type == 'block_begin':
                    flush_data()
                    next(self.stream)
                    if end_tokens is not None and \
                       self.stream.current.test_any(*end_tokens):
                        return body
                    rv = self.parse_statement()
                    if isinstance(rv, list):
                        body.extend(rv)
                    else:
                        body.append(rv)
                    self.stream.expect('block_end')
                else:
                    raise AssertionError('internal parsing error')

            flush_data()
        finally:
            if end_tokens is not None:
                self._end_token_stack.pop()

        return body