How emulators are tested
We run an emulator only when a question needs a real answer. That is an issue, a fix we send to a project, or a check before a release.
A page that relies on a run says so in a Proof line. Every run is on the Measurements page.
What a test does
Section titled “What a test does”- A script runs the emulator with no window and no sound.
- It starts a game and runs it for a set time.
- A test that compares files runs each case at least twice.
- It compares the screens with ones we checked by eye.
- It reads the emulator's log to see which BIOS it ran.
What a result says
Section titled “What a result says”| Result | Meaning |
|---|---|
| works | the game reached a screen it shows when it works |
| works on its built-in BIOS | it worked, but the emulator refused the file and ran its own BIOS |
| BIOS error | the emulator said a BIOS is missing or wrong |
| crash | the emulator stopped |
| hang | the screen stayed blank, or the run never ended |
| unknown | none of these could be shown |
| no verdict | an older test that only compared screens |
What a result does not prove
Section titled “What a result does not prove”- It shows the first minutes of one game, not the whole game.
- It sees the files the emulator opened on this path, not every path.
- Some emulators run their own BIOS when yours is refused. The game still works.
- The app you play in may change settings the test left as they were.
How a file is proven
Section titled “How a file is proven”The game runs with no BIOS and with the BIOS alone. Then it runs with a wrong file under the BIOS name: zeros, half the file, or another region's BIOS.
- Required: no BIOS fails, the BIOS alone works.
- Built-in stand-in: no BIOS still works.
- Checked: a wrong file is refused.
Where results are kept
Section titled “Where results are kept”Each result is a full record in the
measurements/
folder of this project. It names its method, the computer and the exact build
of the emulator. A record is never changed once added.
The results so far ran on these computers:
| Computer | Tests |
|---|---|
| 13th Gen Intel(R) Core(TM) i9-13900K, 12 CPUs, x86_64 Linux 6.18.54.1-microsoft-standard-WSL2, Python 3.12.3 | 224 |