Use ChainMap for UserCommands

[teutoburg]

This makes UserCommands a subclass of astar_utils.NestedChainMap, which is a bang-string-key variant subclass of the standard library's collections.ChainMap. This enables a separation of configuration "layers" into global settings and default, optical train-wide settings and, in the future, effect-level properties and kwargs. Any changes applied through simple assignment (i.e. __setitem__, e.g. cmd["foo"] = 42) will only modify the top layer of this object, thus not influence any other instance building on the same base layer. The individual levels are "by ref", so any change that is applied to the global settings (e.g. logging level) will be seen by all instances. All of this is an advantage over just updating dicts, and potentially making deep copies to avoid cross-contamination.

Additionally, I made some refactoring changes to the rather convoluted .update() method of UserCommands. It's still not quite where I want it to be, but one step at a time. I also added a whole bunch of debug-level logging to, well, debug the YAML loading process, mostly. This could be reduced again in the future, once it's more stable (or once [if] we change the way instrument packages are handled anyway...).

This also bumps the required version of astar-utils to 0.2.2, to include the new bang-string classes from there.

[codecov]

Codecov Report

Attention: Patch coverage is 79.33884% with 25 lines in your changes are missing coverage. Please review.

Project coverage is 74.21%. Comparing base (d786495) to head (d31c490).

Files	Patch %	Lines
scopesim/commands/user_commands.py	78.81%	25 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff               @@
##           dev_master     #375      +/-   ##
==============================================
- Coverage       74.29%   74.21%   -0.08%     
==============================================
  Files              56       56              
  Lines            7818     7854      +36     
==============================================
+ Hits             5808     5829      +21     
- Misses           2010     2025      +15     

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[teutoburg]

Any ideas why the RTD build fails on this @hugobuddel ? I can't really make heads or tails of the error it produces...

[hugobuddel]

Any ideas why the RTD build fails on this @hugobuddel ? I can't really make heads or tails of the error it produces...

No. I just (tried to) rebuild RTD for the dev_master branch and that also fails. So I think it is caused by a change on their end. Maybe we still need to do something, but it is unrelated to this PR I think.

[teutoburg]

3296 Segmentation fault: 11 pip install poetry==1.7.1, lol

[teutoburg]

Any ideas why the RTD build fails on this @hugobuddel ? I can't really make heads or tails of the error it produces...

No. I just (tried to) rebuild RTD for the dev_master branch and that also fails. So I think it is caused by a change on their end. Maybe we still need to do something, but it is unrelated to this PR I think.

Oh yeah, I just saw that the dev_master fails with the same cryptic error. So that's nothing to do with this here. Still annoying...

[teutoburg]

I'll go ahead and merge this. We did discuss it, I addressed the previous review comments and tests are passing.

[hugobuddel]

I'll go ahead and merge this. We did discuss it, I addressed the previous review comments and tests are passing.

Yeah fine. I didn't do a full review yet, as the PR was still marked draft, but we covered the important points.