def exc_from_raise(self, w_arg1, w_arg2):
"""
Create a wrapped exception from the arguments of a raise statement.
Returns an FSException object whose w_value is an instance of w_type.
"""
w_is_type = op.simple_call(const(isinstance), w_arg1, const(type)).eval(self)
if self.guessbool(w_is_type):
# this is for all cases of the form (Class, something)
if self.guessbool(op.is_(w_arg2, w_None).eval(self)):
# raise Type: we assume we have to instantiate Type
w_value = op.simple_call(w_arg1).eval(self)
else:
w_valuetype = op.type(w_arg2).eval(self)
if self.guessbool(op.issubtype(w_valuetype, w_arg1).eval(self)):
# raise Type, Instance: let etype be the exact type of value
w_value = w_arg2
else:
# raise Type, X: assume X is the constructor argument
w_value = op.simple_call(w_arg1, w_arg2).eval(self)
else:
# the only case left here is (inst, None), from a 'raise inst'.
if not self.guessbool(op.is_(w_arg2, const(None)).eval(self)):
exc = TypeError("instance exception may not have a "
"separate value")
raise Raise(const(exc))
w_value = w_arg1
w_type = op.type(w_value).eval(self)
return FSException(w_type, w_value)
def exc_from_raise(self, w_arg1, w_arg2):
"""
Create a wrapped exception from the arguments of a raise statement.
Returns an FSException object whose w_value is an instance of w_type.
"""
w_is_type = op.simple_call(const(isinstance), w_arg1, const(type)).eval(self)
if self.guessbool(w_is_type):
# this is for all cases of the form (Class, something)
if self.guessbool(op.is_(w_arg2, w_None).eval(self)):
# raise Type: we assume we have to instantiate Type
w_value = op.simple_call(w_arg1).eval(self)
else:
w_valuetype = op.type(w_arg2).eval(self)
if self.guessbool(op.issubtype(w_valuetype, w_arg1).eval(self)):
# raise Type, Instance: let etype be the exact type of value
w_value = w_arg2
else:
# raise Type, X: assume X is the constructor argument
w_value = op.simple_call(w_arg1, w_arg2).eval(self)
else:
# the only case left here is (inst, None), from a 'raise inst'.
if not self.guessbool(op.is_(w_arg2, const(None)).eval(self)):
exc = TypeError("instance exception may not have a "
"separate value")
raise Raise(const(exc))
w_value = w_arg1
w_type = op.type(w_value).eval(self)
return FSException(w_type, w_value)
def exception_match(self, w_exc_type, w_check_class):
"""Checks if the given exception type matches 'w_check_class'."""
if not isinstance(w_check_class, Constant):
raise FlowingError("Non-constant except guard.")
check_class = w_check_class.value
if check_class in (NotImplementedError, AssertionError):
raise FlowingError(
"Catching %s is not valid in RPython" % check_class.__name__)
if not isinstance(check_class, tuple):
# the simple case
return self.guessbool(op.issubtype(w_exc_type, w_check_class).eval(self))
# special case for StackOverflow (see rlib/rstackovf.py)
if check_class == rstackovf.StackOverflow:
w_real_class = const(rstackovf._StackOverflow)
return self.guessbool(op.issubtype(w_exc_type, w_real_class).eval(self))
# checking a tuple of classes
for klass in w_check_class.value:
if self.exception_match(w_exc_type, const(klass)):
return True
return False
def exception_match(self, w_exc_type, w_check_class):
"""Checks if the given exception type matches 'w_check_class'."""
if not isinstance(w_check_class, Constant):
raise FlowingError("Non-constant except guard.")
check_class = w_check_class.value
if check_class in (NotImplementedError, AssertionError):
raise FlowingError(
"Catching %s is not valid in RPython" % check_class.__name__)
if not isinstance(check_class, tuple):
# the simple case
return self.guessbool(op.issubtype(w_exc_type, w_check_class).eval(self))
# special case for StackOverflow (see rlib/rstackovf.py)
if check_class == rstackovf.StackOverflow:
w_real_class = const(rstackovf._StackOverflow)
return self.guessbool(op.issubtype(w_exc_type, w_real_class).eval(self))
# checking a tuple of classes
for klass in w_check_class.value:
if self.exception_match(w_exc_type, const(klass)):
return True
return False
