tests/test_debug.py

import pickle
import re
from traceback import format_exception

import pytest

from jinja2 import ChoiceLoader
from jinja2 import DictLoader
from jinja2 import Environment
from jinja2 import TemplateSyntaxError


@pytest.fixture
def fs_env(filesystem_loader):
    """returns a new environment."""
    return Environment(loader=filesystem_loader)


class TestDebug:
    def assert_traceback_matches(self, callback, expected_tb):
        with pytest.raises(Exception) as exc_info:
            callback()

        tb = format_exception(exc_info.type, exc_info.value, exc_info.tb)
        m = re.search(expected_tb.strip(), "".join(tb))
        assert (
            m is not None
        ), "Traceback did not match:\n\n{''.join(tb)}\nexpected:\n{expected_tb}"

    def test_runtime_error(self, fs_env):
        def test():
            tmpl.render(fail=lambda: 1 / 0)

        tmpl = fs_env.get_template("broken.html")
        self.assert_traceback_matches(
            test,
            r"""
  File ".*?broken.html", line 2, in (top-level template code|<module>)
    \{\{ fail\(\) \}\}
  File ".*debug?.pyc?", line \d+, in <lambda>
    tmpl\.render\(fail=lambda: 1 / 0\)
ZeroDivisionError: (int(eger)? )?division (or modulo )?by zero
""",
        )

    def test_syntax_error(self, fs_env):
        # The trailing .*? is for PyPy 2 and 3, which don't seem to
        # clear the exception's original traceback, leaving the syntax
        # error in the middle of other compiler frames.
        self.assert_traceback_matches(
            lambda: fs_env.get_template("syntaxerror.html"),
            """(?sm)
  File ".*?syntaxerror.html", line 4, in (template|<module>)
    \\{% endif %\\}.*?
(jinja2\\.exceptions\\.)?TemplateSyntaxError: Encountered unknown tag 'endif'. Jinja \
was looking for the following tags: 'endfor' or 'else'. The innermost block that needs \
to be closed is 'for'.
    """,
        )

    def test_regular_syntax_error(self, fs_env):
        def test():
            raise TemplateSyntaxError("wtf", 42)

        self.assert_traceback_matches(
            test,
            r"""
  File ".*debug.pyc?", line \d+, in test
    raise TemplateSyntaxError\("wtf", 42\)
(jinja2\.exceptions\.)?TemplateSyntaxError: wtf
  line 42""",
        )

    def test_pickleable_syntax_error(self, fs_env):
        original = TemplateSyntaxError("bad template", 42, "test", "test.txt")
        unpickled = pickle.loads(pickle.dumps(original))
        assert str(original) == str(unpickled)
        assert original.name == unpickled.name

    def test_include_syntax_error_source(self, filesystem_loader):
        e = Environment(
            loader=ChoiceLoader(
                [
                    filesystem_loader,
                    DictLoader({"inc": "a\n{% include 'syntaxerror.html' %}\nb"}),
                ]
            )
        )
        t = e.get_template("inc")

        with pytest.raises(TemplateSyntaxError) as exc_info:
            t.render()

        assert exc_info.value.source is not None

    def test_local_extraction(self):
        from jinja2.debug import get_template_locals
        from jinja2.runtime import missing

        locals = get_template_locals(
            {
                "l_0_foo": 42,
                "l_1_foo": 23,
                "l_2_foo": 13,
                "l_0_bar": 99,
                "l_1_bar": missing,
                "l_0_baz": missing,
            }
        )
        assert locals == {"foo": 13, "bar": 99}

    def test_get_corresponding_lineno_traceback(self, fs_env):
        tmpl = fs_env.get_template("test.html")
        assert tmpl.get_corresponding_lineno(1) == 1