You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
192 lines
6.2 KiB
Python
192 lines
6.2 KiB
Python
import sys
|
|
import typing as t
|
|
from types import CodeType
|
|
from types import TracebackType
|
|
|
|
from .exceptions import TemplateSyntaxError
|
|
from .utils import internal_code
|
|
from .utils import missing
|
|
|
|
if t.TYPE_CHECKING:
|
|
from .runtime import Context
|
|
|
|
|
|
def rewrite_traceback_stack(source: t.Optional[str] = None) -> BaseException:
|
|
"""Rewrite the current exception to replace any tracebacks from
|
|
within compiled template code with tracebacks that look like they
|
|
came from the template source.
|
|
|
|
This must be called within an ``except`` block.
|
|
|
|
:param source: For ``TemplateSyntaxError``, the original source if
|
|
known.
|
|
:return: The original exception with the rewritten traceback.
|
|
"""
|
|
_, exc_value, tb = sys.exc_info()
|
|
exc_value = t.cast(BaseException, exc_value)
|
|
tb = t.cast(TracebackType, tb)
|
|
|
|
if isinstance(exc_value, TemplateSyntaxError) and not exc_value.translated:
|
|
exc_value.translated = True
|
|
exc_value.source = source
|
|
# Remove the old traceback, otherwise the frames from the
|
|
# compiler still show up.
|
|
exc_value.with_traceback(None)
|
|
# Outside of runtime, so the frame isn't executing template
|
|
# code, but it still needs to point at the template.
|
|
tb = fake_traceback(
|
|
exc_value, None, exc_value.filename or "<unknown>", exc_value.lineno
|
|
)
|
|
else:
|
|
# Skip the frame for the render function.
|
|
tb = tb.tb_next
|
|
|
|
stack = []
|
|
|
|
# Build the stack of traceback object, replacing any in template
|
|
# code with the source file and line information.
|
|
while tb is not None:
|
|
# Skip frames decorated with @internalcode. These are internal
|
|
# calls that aren't useful in template debugging output.
|
|
if tb.tb_frame.f_code in internal_code:
|
|
tb = tb.tb_next
|
|
continue
|
|
|
|
template = tb.tb_frame.f_globals.get("__jinja_template__")
|
|
|
|
if template is not None:
|
|
lineno = template.get_corresponding_lineno(tb.tb_lineno)
|
|
fake_tb = fake_traceback(exc_value, tb, template.filename, lineno)
|
|
stack.append(fake_tb)
|
|
else:
|
|
stack.append(tb)
|
|
|
|
tb = tb.tb_next
|
|
|
|
tb_next = None
|
|
|
|
# Assign tb_next in reverse to avoid circular references.
|
|
for tb in reversed(stack):
|
|
tb.tb_next = tb_next
|
|
tb_next = tb
|
|
|
|
return exc_value.with_traceback(tb_next)
|
|
|
|
|
|
def fake_traceback( # type: ignore
|
|
exc_value: BaseException, tb: t.Optional[TracebackType], filename: str, lineno: int
|
|
) -> TracebackType:
|
|
"""Produce a new traceback object that looks like it came from the
|
|
template source instead of the compiled code. The filename, line
|
|
number, and location name will point to the template, and the local
|
|
variables will be the current template context.
|
|
|
|
:param exc_value: The original exception to be re-raised to create
|
|
the new traceback.
|
|
:param tb: The original traceback to get the local variables and
|
|
code info from.
|
|
:param filename: The template filename.
|
|
:param lineno: The line number in the template source.
|
|
"""
|
|
if tb is not None:
|
|
# Replace the real locals with the context that would be
|
|
# available at that point in the template.
|
|
locals = get_template_locals(tb.tb_frame.f_locals)
|
|
locals.pop("__jinja_exception__", None)
|
|
else:
|
|
locals = {}
|
|
|
|
globals = {
|
|
"__name__": filename,
|
|
"__file__": filename,
|
|
"__jinja_exception__": exc_value,
|
|
}
|
|
# Raise an exception at the correct line number.
|
|
code: CodeType = compile(
|
|
"\n" * (lineno - 1) + "raise __jinja_exception__", filename, "exec"
|
|
)
|
|
|
|
# Build a new code object that points to the template file and
|
|
# replaces the location with a block name.
|
|
location = "template"
|
|
|
|
if tb is not None:
|
|
function = tb.tb_frame.f_code.co_name
|
|
|
|
if function == "root":
|
|
location = "top-level template code"
|
|
elif function.startswith("block_"):
|
|
location = f"block {function[6:]!r}"
|
|
|
|
if sys.version_info >= (3, 8):
|
|
code = code.replace(co_name=location)
|
|
else:
|
|
code = CodeType(
|
|
code.co_argcount,
|
|
code.co_kwonlyargcount,
|
|
code.co_nlocals,
|
|
code.co_stacksize,
|
|
code.co_flags,
|
|
code.co_code,
|
|
code.co_consts,
|
|
code.co_names,
|
|
code.co_varnames,
|
|
code.co_filename,
|
|
location,
|
|
code.co_firstlineno,
|
|
code.co_lnotab,
|
|
code.co_freevars,
|
|
code.co_cellvars,
|
|
)
|
|
|
|
# Execute the new code, which is guaranteed to raise, and return
|
|
# the new traceback without this frame.
|
|
try:
|
|
exec(code, globals, locals)
|
|
except BaseException:
|
|
return sys.exc_info()[2].tb_next # type: ignore
|
|
|
|
|
|
def get_template_locals(real_locals: t.Mapping[str, t.Any]) -> t.Dict[str, t.Any]:
|
|
"""Based on the runtime locals, get the context that would be
|
|
available at that point in the template.
|
|
"""
|
|
# Start with the current template context.
|
|
ctx: "t.Optional[Context]" = real_locals.get("context")
|
|
|
|
if ctx is not None:
|
|
data: t.Dict[str, t.Any] = ctx.get_all().copy()
|
|
else:
|
|
data = {}
|
|
|
|
# Might be in a derived context that only sets local variables
|
|
# rather than pushing a context. Local variables follow the scheme
|
|
# l_depth_name. Find the highest-depth local that has a value for
|
|
# each name.
|
|
local_overrides: t.Dict[str, t.Tuple[int, t.Any]] = {}
|
|
|
|
for name, value in real_locals.items():
|
|
if not name.startswith("l_") or value is missing:
|
|
# Not a template variable, or no longer relevant.
|
|
continue
|
|
|
|
try:
|
|
_, depth_str, name = name.split("_", 2)
|
|
depth = int(depth_str)
|
|
except ValueError:
|
|
continue
|
|
|
|
cur_depth = local_overrides.get(name, (-1,))[0]
|
|
|
|
if cur_depth < depth:
|
|
local_overrides[name] = (depth, value)
|
|
|
|
# Modify the context with any derived context.
|
|
for name, (_, value) in local_overrides.items():
|
|
if value is missing:
|
|
data.pop(name, None)
|
|
else:
|
|
data[name] = value
|
|
|
|
return data
|