Decompile mistake with nested if/else + and conditions

Start with the attached toto.py example, compile it for Python 3.8, and run decompyle3/bin/decompile.py on the resulting toto.cpython-38.pyc. Trace the nested if/else handling that produces the shown indentation and control-flow error. Done means the decompiled output places the print and return outside the inner conditions while preserving the intended else behavior.

Description

The following code will decompile incorrectly with pyhon 3.8 :

def toto(a, b, c):
	if c:
		if a and b:
				print('a and b')
		print('c, whatever a/b')
		return
	else:
		raise ValueError('not a or not b')

Decompilation result :

def toto(a, b, c):
    if c:
        if a:
            if b:
                print('a and b')
            print('c, whatever a/b')
            return
    raise ValueError('not a or not b')

As you can see the print and return are still within a condition instead of being one indentation level up.

How to Reproduce

I attach the examples although they are quite easy to reproduce.

toto.zip

(.env) C:\work\logh_home\decomp-tests>python -m py_compile toto.py

(.env) C:\work\logh_home\decomp-tests>python ..\python-decompile3\decompyle3\bin\decompile.py __pycache__\toto.cpython-38.pyc
# decompyle3 version 3.9.1.dev0
# Python bytecode version base 3.8.0 (3413)
# Decompiled from: Python 3.8.10 (tags/v3.8.10:3d8993a, May  3 2021, 11:34:34) [MSC v.1928 32 bit (Intel)]
# Embedded file name: toto.py
# Compiled at: 2023-11-16 12:28:39
# Size of source mod 2**32: 153 bytes


def toto(a, b, c):
    if c:
        if a:
            if b:
                print('a and b')
            print('c, whatever a/b')
            return
    raise ValueError('not a or not b')

# okay decompiling __pycache__\toto.cpython-38.pyc

(.env) C:\work\logh_home\decomp-tests>

Environment

(.env) C:\work\logh_home\python-decompile3>git log -1
commit ed375df6b21ecbddd21cf6aaa37c7673da876751 (HEAD -> master, origin/master, origin/HEAD)
Author: rocky <rb@dustyfeet.com>
Date:   Mon Nov 13 08:09:43 2023 -0500

    Forgot to add these to the last commit

(.env) C:\work\logh_home>pip list
Package      Version    Location
------------ ---------- -----------------------------------
click        8.1.7
colorama     0.4.6
decompyle3   3.9.1.dev0 c:\work\logh_home\python-decompile3
pip          21.1.2
setuptools   57.0.0
six          1.16.0
spark-parser 1.8.9
wheel        0.36.2
xdis         6.1.0.dev0
WARNING: You are using pip version 21.1.2; however, version 23.3.1 is available.
You should consider upgrading via the 'C:\work\logh_home\decomp-tests\.env\Scripts\python.exe -m pip install --upgrade pip' command.



(.env) C:\work\logh_home>python --version
Python 3.8.10

Windows 10 22H2

Priority

Up to you.

Additional Context

I lost the source code of the binary release of one of my software.

So, I am in the interesting position where I know very well the original source code, and I am still very interested in recovering it fully, and I can spot mistakes.

In this case, I have a state machine for parsing a file, with deep if/else flow.

And of course, I like open source.