app/django/template/debug.py
author Pawel Solyga <Pawel.Solyga@gmail.com>
Mon, 17 Nov 2008 22:12:34 +0000
changeset 501 be89bf307478
parent 54 03e267d67478
permissions -rw-r--r--
Fix not working feed display for home settings public view. Modify blog javascript so that we can define how many feed entries we want to display. Change default number of entries to 3 as suggested by Leslie and Chris. Patch by: Pawel Solyga

from django.template import Lexer, Parser, tag_re, NodeList, VariableNode, TemplateSyntaxError
from django.utils.encoding import force_unicode
from django.utils.html import escape
from django.utils.safestring import SafeData, EscapeData

class DebugLexer(Lexer):
    def __init__(self, template_string, origin):
        super(DebugLexer, self).__init__(template_string, origin)

    def tokenize(self):
        "Return a list of tokens from a given template_string"
        result, upto = [], 0
        for match in tag_re.finditer(self.template_string):
            start, end = match.span()
            if start > upto:
                result.append(self.create_token(self.template_string[upto:start], (upto, start), False))
                upto = start
            result.append(self.create_token(self.template_string[start:end], (start, end), True))
            upto = end
        last_bit = self.template_string[upto:]
        if last_bit:
            result.append(self.create_token(last_bit, (upto, upto + len(last_bit)), False))
        return result

    def create_token(self, token_string, source, in_tag):
        token = super(DebugLexer, self).create_token(token_string, in_tag)
        token.source = self.origin, source
        return token

class DebugParser(Parser):
    def __init__(self, lexer):
        super(DebugParser, self).__init__(lexer)
        self.command_stack = []

    def enter_command(self, command, token):
        self.command_stack.append( (command, token.source) )

    def exit_command(self):
        self.command_stack.pop()

    def error(self, token, msg):
        return self.source_error(token.source, msg)

    def source_error(self, source,msg):
        e = TemplateSyntaxError(msg)
        e.source = source
        return e

    def create_nodelist(self):
        return DebugNodeList()

    def create_variable_node(self, contents):
        return DebugVariableNode(contents)

    def extend_nodelist(self, nodelist, node, token):
        node.source = token.source
        super(DebugParser, self).extend_nodelist(nodelist, node, token)

    def unclosed_block_tag(self, parse_until):
        command, source = self.command_stack.pop()
        msg = "Unclosed tag '%s'. Looking for one of: %s " % (command, ', '.join(parse_until))
        raise self.source_error(source, msg)

    def compile_function_error(self, token, e):
        if not hasattr(e, 'source'):
            e.source = token.source

class DebugNodeList(NodeList):
    def render_node(self, node, context):
        try:
            result = node.render(context)
        except TemplateSyntaxError, e:
            if not hasattr(e, 'source'):
                e.source = node.source
            raise
        except Exception, e:
            from sys import exc_info
            wrapped = TemplateSyntaxError(u'Caught an exception while rendering: %s' % force_unicode(e, errors='replace'))
            wrapped.source = node.source
            wrapped.exc_info = exc_info()
            raise wrapped
        return result

class DebugVariableNode(VariableNode):
    def render(self, context):
        try:
            output = force_unicode(self.filter_expression.resolve(context))
        except TemplateSyntaxError, e:
            if not hasattr(e, 'source'):
                e.source = self.source
            raise
        except UnicodeDecodeError:
            return ''
        if (context.autoescape and not isinstance(output, SafeData)) or isinstance(output, EscapeData):
            return escape(output)
        else:
            return output