# Process replay
Process replay is a regression test designed to identify any changes in the output of a process. This test replays a segment through individual processes and compares the output to a known good replay. Each make is represented in the test with a segment.
If the test fails, make sure that you didn't unintentionally change anything. If there are intentional changes, the reference logs will be updated.
Use `test_processes.py` to run the test locally.
Use `FILEREADER_CACHE='1' test_processes.py` to cache log files.
Currently the following processes are tested:
* controlsd
* radard
* plannerd
* calibrationd
* dmonitoringd
* locationd
* laikad
* paramsd
* ubloxd
### Usage
```
Usage: test_processes.py [-h] [--whitelist-procs PROCS] [--whitelist-cars CARS] [--blacklist-procs PROCS]
[--blacklist-cars CARS] [--ignore-fields FIELDS] [--ignore-msgs MSGS] [--update-refs] [--upload-only]
Regression test to identify changes in a process's output
optional arguments:
-h, --help show this help message and exit
--whitelist-procs PROCS Whitelist given processes from the test (e.g. controlsd)
--whitelist-cars WHITELIST_CARS Whitelist given cars from the test (e.g. HONDA)
--blacklist-procs BLACKLIST_PROCS Blacklist given processes from the test (e.g. controlsd)
--blacklist-cars BLACKLIST_CARS Blacklist given cars from the test (e.g. HONDA)
--ignore-fields IGNORE_FIELDS Extra fields or msgs to ignore (e.g. carState.events)
--ignore-msgs IGNORE_MSGS Msgs to ignore (e.g. carEvents)
--update-refs Updates reference logs using current commit
--upload-only Skips testing processes and uploads logs from previous test run
```
## Forks
openpilot forks can use this test with their own reference logs, by default `test_proccess.py` saves logs locally.
To generate new logs:
`./test_processes.py`
Then, check in the new logs using git-lfs. Make sure to also update the `ref_commit` file to the current commit.
