Revert in an internal function leads to a crash

[Leminkay]

Boa commit: f58c33cde50f6deaaeefff1136b18f92ef747c6b

import boa

code = f"""
@internal
def func_0():
    raise
    
@external
def func_1():
    raise
"""

ct = boa.loads(code)
try:
    res = ct.internal.func_0()
    #res = ct.func_1()
    print(res.output)
except Exception as e:
    print(e)

Calling an internal function will throw an error:

Traceback (most recent call last):
  File "/home/lemy/otitanoboa/titanoboa/test_except.py", line 19, in <module>
    res = ct.internal.func_0()
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/vyper/vyper_contract.py", line 1075, in __call__
    return self.contract.marshal_to_python(computation, typ)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/vyper/vyper_contract.py", line 782, in marshal_to_python
    self.handle_error(computation)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/base_evm_contract.py", line 51, in handle_error
    raise strip_internal_frames(b) from b
  File "/home/lemy/otitanoboa/titanoboa/test_except.py", line 19, in <module>
    res = ct.internal.func_0()
boa.contracts.base_evm_contract.BoaError: <exception str() failed>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/lemy/otitanoboa/titanoboa/test_except.py", line 23, in <module>
    print(e)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/base_evm_contract.py", line 132, in __str__
    call_tree = str(self.call_trace)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/call_trace.py", line 97, in __str__
    text = f"{' ' * self.depth * 4}{self.text}"
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/call_trace.py", line 103, in text
    text = self.source.format(self.input_data, self.output, self.is_error)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/call_trace.py", line 15, in format
    in_ = self._format_input(input_)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/call_trace.py", line 25, in _format_input
    decoded = abi_decode(self.args_abi_type, input_)
  File "/usr/lib/python3.10/functools.py", line 981, in __get__
    val = self.func(instance)
  File "/home/lemy/otitanoboa/titanoboa/boa/contracts/vyper/vyper_contract.py", line 1135, in args_abi_type
    schema, fn_t = self._func_t_helper
TypeError: cannot unpack non-iterable NoneType object