Event Handler Infrastructure

[Alomir]

This PR adds infrastructure to SIPNET to enable handling of agronomic events.

Structure

• Use a compile-time flag to turn this functionality on/off
• Put this flag (and similar future flags) in a separate file to allow for easier testing (by having only one file that needs to be replaced to control tested functionality, and also to have nothing else in that file)
• Create unit test(s)
• Update the github workflow to run the new tests

Design

• Read event information from a specified file, one line per event.
• The spec for the agronomic events is here; a reviewer with access to that doc should make sure this code follows that spec.
• Store event information in a similar fashion as climate data
• Future (next step, really): augment sipnet.c to fetch the appropriate events at a given location in the now-empty setupEvents function

Testing

• This is an attempt (first try?) at adding some infrastructure for unit testing.
• Basic idea:
  • Unit tests go in a subdirectory of /tests/sipnet (or another sub of /tests/, if we add specific testing for, say, estimate)
  • Create a model_structures.h file with the correct compile switches for the functionality to be tested
  • Copy /tests/Makefile.template and add the test c-files to it
  • ...and write the tests, of course. The infrastructure should handle the rest.
  • See tests/sipnet/test_events for an example

Notes

• frontend.c: it was tempting to simplify this code by removing the #if checks for EVENT_
  HANDLER, but that seemed out of character for SIPNET
• sipnet.c: I commented out some variable declarations to clean up compiler warnings

[dlebauer]

I'm am generally unfamiliar with C but learning - is this line intended to be similar to the check on line 87?

[Alomir]

Yes, it is - and it's possibly redundant. Line 87 catches bad data in the file, and 135 here catches a bad return from getEventType. I think right now there's no likely way to to get past the line 87 check and hit the 135 check, but that might not be true in the future.

[dlebauer]

Thank you for this contribution, it is exciting to have the project under way. Although my experience with C is limited, this looks like a great start that provides a solid foundation. 🎉

Great work with the comprehensive testing - I did not previously appreciate the complexity of testing in C! Also with checks for a valid events file and helpful corrective guidance.

With respect to migrating compile time flags to a separate file - is this a relatively straightforward cut and paste? If not / if it would help, I can provide a list of flags that are higher priority since we will be changing from the defaults.

Sorry I made some minor changes (mostly to Makefile and ci.yml after mergeing #21 and then resolving merge conflicts); these can be seen here: 0d8d16c...93adfd1

Not urgent, but if you document how to add a test it could help to delegate some of the testing (I haven't taken the time to understand how this works, but it looks daunting).

[Alomir]

I agree, we need some docs for adding tests. They are a bit daunting - some of that is due to this being C, but also needing to recompile to enable functionality really brings it up a notch. I hope I've hidden most of that, time will tell 🤞