[pydrake] Begin adding typed (i.e., schema-based) YAML loading

[jwnimmer-tri]

Towards #18566 (and therefore #17112).

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This change is 

[jwnimmer-tri]

Reviewed 2 of 4 files at r1.
Reviewable status: needs platform reviewer assigned, needs at least two assigned reviewers, labeled "do not merge"

[jwnimmer-tri]

This is ready for feature review, either @SeanCurtis-TRI or @rpoyner-tri?

[jwnimmer-tri]

Reviewable status: 1 unresolved discussion, needs platform reviewer assigned, needs at least two assigned reviewers (waiting on @jwnimmer-tri)

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bindings/pydrake/common/yaml.py line 152 at r2 (raw file):

    fields = getattr(obj, "__fields__", None)
    if fields is not None:
        return dict([

This branch isn't unit tested yet. (Coming in the future). I should either TODO it for unit testing, or yank it until the next PR.

[jwnimmer-tri]

Reviewable status: needs platform reviewer assigned, needs at least two assigned reviewers

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bindings/pydrake/common/yaml.py line 152 at r2 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

This branch isn't unit tested yet. (Coming in the future). I should either TODO it for unit testing, or yank it until the next PR.

Done.

[rpoyner-tri]

+@rpoyner-tri feature.

Reviewable status: LGTM missing from assignee rpoyner-tri(platform), needs at least two assigned reviewers

[jwnimmer-tri]

bindings/pydrake/common/yaml.py line 141 at r3 (raw file):

def _enumerate_field_types(obj):
    """Returns a Mapping[str, type] of the schema-based field names and types
    of the given object `obj`. (Note that `obj` is a value, not a type.)

I think this comment might be wrong. I'll work on improving / confirming.

Code quote:

(Note that `obj` is a value, not a type.)

[jwnimmer-tri]

Reviewable status: LGTM missing from assignee rpoyner-tri(platform), needs at least two assigned reviewers (waiting on @rpoyner-tri)

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bindings/pydrake/common/yaml.py line 141 at r3 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

I think this comment might be wrong. I'll work on improving / confirming.

Done.

[rpoyner-tri]

Reviewed 1 of 4 files at r1, 4 of 5 files at r2, 1 of 1 files at r4, all commit messages.
Reviewable status: 2 unresolved discussions, needs at least two assigned reviewers (waiting on @jwnimmer-tri)

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bindings/pydrake/common/test/yaml_typed_test.py line 283 at r4 (raw file):

    @run_with_multiple_values(_all_typed_read_options())
    def test_read_optional(self, *, options):
        # The test case numberes here (1..12) reference the specification as

typo

Suggestion:

numbers

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bindings/pydrake/common/test/yaml_typed_test.py line 395 at r4 (raw file):

class TestYamlTypedReadAccepatance(unittest.TestCase):

typo

Suggestion:

Acceptance

[jwnimmer-tri]

+@xuchenhan-tri for platform review per schedule, please. (Feel free to spill to Eric tomorrow if need be.)

[xuchenhan-tri]

Platform

I gave a best-effort review. Feel free to tag a reviewer with more Python experience if in doubt.

Reviewed 1 of 4 files at r1, 3 of 5 files at r2, 2 of 2 files at r5, all commit messages.
Reviewable status: 1 unresolved discussion (waiting on @jwnimmer-tri)

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bindings/pydrake/common/test/yaml_typed_test.py line 303 at r5 (raw file):

                    else:
                        amended_data = "foo: bar"
                    actual = yaml_load_typed(

nit, typo

Suggestion:

                    actual = yaml_load_typed(
                        schema=schema, data=amended_data, **options)

[jwnimmer-tri]

I gave a best-effort review. Feel free to tag a reviewer with more Python experience if in doubt.

I am going to keep the PR train moving, but \CC @EricCousineau-TRI in case you'd like to give it a once-over. In any case I'll plan to ping you (Eric) once the new subsystem is complete, so you can take a look. It will be similar to the Python schema stuff in Anzu, except that here I don't plan to enforce anything with numpy types yet. (I plan to use numpy.typing to that effect, eventually; just not this quarter.)

[jwnimmer-tri]

Reviewable status: complete! all discussions resolved, LGTM from assignees rpoyner-tri(platform),xuchenhan-tri(platform) (waiting on @xuchenhan-tri)

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bindings/pydrake/common/test/yaml_typed_test.py line 303 at r5 (raw file):

Previously, xuchenhan-tri wrote…

nit, typo

Yikes! Thanks, fixed.

[xuchenhan-tri]

Reviewed 1 of 1 files at r6, all commit messages.
Reviewable status: complete! all discussions resolved, LGTM from assignees rpoyner-tri(platform),xuchenhan-tri(platform) (waiting on @jwnimmer-tri)