reverse generated-python direction

[minrk]

Make binderspawner_mixin.py canonical, instead of python-in-yaml

easier to edit with editors, linters, etc.

removes use of redundant pyyaml in favor of ruamel.yaml, needed for roundtrip yaml editing

[manics]

This duplication is something that annoys me too 😞 . Good to merge once the tests are passing.

In future we could probably add this to pre-commit so the scripts gets updated automatically as part of linting.

[consideRatio]

If you use a round trip, the quotes may not be left for a string that needs them i think.

Retainig explicit quotes for the tag has been relevant in the past i recall, perhaps not by chartpress generates image tags, but i'm still cautious preferring to see us having the yaml include quotes foe our placeholder values where they could be needed.

[minrk]

The quotes were removed by the roundtrip serialization. I did not remove them. I left the change here because every re-write of the file will strip it.

[consideRatio]

Ah, this is how we have configured ruamel.yaml in chartpress to avoid this kind of issue.

# use safe roundtrip yaml loader capable or preserving usage of no/single/double
# quotes for a string for example
yaml = YAML(typ="rt")
yaml.preserve_quotes = True
yaml.indent(mapping=2, offset=2, sequence=4)

The indent settings is relevant to be compatible with prettier formatting, at least if not having a rout-tripped format to retain.

exampleList:
- without-indent-settings

# this is the kind of formatting we systematically
# use and enforce with prettier, and requires explicit
# configuration of ruamel.yaml at least when generating
# new yaml files, but I'm uncertain if it's required when
# round-tripping on existing files with existing list entries
anotherExampleList:
  - with-indent-settings

[minrk]

Got it! I remembered the indent setting (it's the same here), but forgot the quotes. Will fix.

[minrk]

Fixed.