Reproducable builds, Basic CI

[cpresser]

Hi,

while working on #604 I did some manual checking if the changes to KicadModTree break any existing footprints.
My approach was to run the bga and nolead generators with find *.yaml -exec . Then repeat the same on the master and compare results with diff.
Fortunately diff has a -I option so I could do diff -ru -I tedit _604/ _m/ to ignore the timestamp lines.

When I was done my thought was 'why not automate that in a CI pipeline'. For that it would be nice if there is --reproducible command line argument to fix the timestamp.

Any comments? Good or bad idea? Implementation hints?

[calebreister]

I like the idea of making scripts reproducible, but I'm wondering if the scripts directory is too much of a mess to make it work reliably. Also, I'm beginning to wonder if it would be a good idea to port the data files to JSON since support is built into the python standard libraries.

[cpresser]

I would start with the IPC generators and perhaps add more later.
Regarding the JSON support, does it also support comments in the JSON file? That's a feature I wouldn't want to miss.

[calebreister]

JSON doesn't support comments, though you could embed comments in the data and disregard it in the code. Just add a string to your object and name it "_" or something. The main reason to switch is that JSON is far simpler (and less error-prone) than YAML; and with the addition of scripts/tools/dict_tools.py, YAML references using & and * are no longer needed.