retro VS 6502_65C02_functional_tests

https://github.com/openai/retro:

> Gym Retro lets you turn classic video games into Gym environments for reinforcement learning and comes with integrations for ~1000 games. It uses various emulators that support the Libretro API, making it fairly easy to add new emulators.

.nes is listed in the supported ROM types:

OpenAI Retro Gym hasn't been updated in years, despite being high profile enough to garner 3k stars. It doesn't even support Python 3.9, and needs old versions of setuptools and gym to get installed.

The trajectories might not be properly generated (I used a custom wrapper for the retro gym that allows the env to receive human input: Interactive Gym-Retro), so the GAIL agent is just following garbage.

You can do it yourself. Maybe with retro

Another alternative is OpenAI gyms. For example, this supports NES, SNES, and GB.

Klaus Dormann's 6502 tests don't rely on a particular emulator environment. They could be used with Ghidra.

https://github.com/Klaus2m5/6502_65C02_functional_tests

How about some assembler code to test all of the opcodes? https://github.com/klaus2m5/6502_65c02_functional_tests

https://github.com/Klaus2m5/6502_65C02_functional_tests might be worth a look, it's a comprehensive test suite

Great! (and not surprising). You may want to look into using a 6520 test suite to check correctness of your emulator, like this one -- note: I have no experience with it, but it took me some time to iron out the last error of my 6502 emulator, and in hindsight I should probably have used such test suite.

Currently i'm trying to implement 6502's instructions one by one using TDD. I was curious are there any test - corner cases already been written ? I found out ( https://github.com/Klaus2m5/6502_65C02_functional_tests ) but this requires all instructions to be implemented which I don't currently. Is there any way to test a single instruction in isolation for all the edge cases ?

By "bad branch", I mean the emulator takes the wrong branch because it fails to emulate some part of the Apple hardware properly. The 65C02 emulation has passed some pretty stringent tests (https://github.com/Klaus2m5/6502_65C02_functional_tests/blob/master/bin_files/65C02_extended_opcodes_test.lst), so I'm pretty confident in it. But the instruction trace file is around 90,000 lines, so is kinda hard to slog through.