Fixed the rendering of the metadata argument with SQLModel

[agronholm]

Changes

This fixes the missing metadata argument when rendering a plain Table with the SQLModel generator.
It contains a hack that replaces self.base.metadata_ref which is otherwise overridden by the declarative generator during generate_models().

Fixes #465.

Checklist

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you've fulfilled the following conditions (where applicable):

• You've added tests (in tests/) which would fail without your patch
• You've added a new changelog entry (in CHANGES.rst).

If this is a trivial change, like a typo fix or a code reformatting, then you can ignore
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Updating the changelog

If there are no entries after the last release, use **UNRELEASED** as the version.
If, say, your patch fixes issue #123, the entry should look like this:

- Fix big bad boo-boo in task groups
  (`#123 <https://github.com/agronholm/sqlacodegen/issues/123>`_; PR by @yourgithubaccount)

If there's no issue linked, just link to your pull request instead by updating the
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[coveralls]

coverage: 97.785% (+0.1%) from 97.668%
when pulling 84e3aa7 on fix-465
into 94878f9 on master.

[sheinbergon]

Changes

This fixes the missing metadata argument when rendering a plain Table with the SQLModel generator. It contains a hack that replaces self.base.metadata_ref which is otherwise overridden by the declarative generator during generate_models().

You can probably juat extract the metadata_ref in the base class instead of overriding and calling the super, which would also make things less hacky.

[agronholm]

Changes

This fixes the missing metadata argument when rendering a plain Table with the SQLModel generator. It contains a hack that replaces self.base.metadata_ref which is otherwise overridden by the declarative generator during generate_models().

You can probably juat extract the metadata_ref in the base class instead of overriding and calling the super, which would also make things less hacky.

I have no idea what this would mean in practice.

[agronholm]

The core problem is that DeclarativeModelGenerator.generate_models() steamrolls self.base if it detects that there are no model classes.

[agronholm]

I came up with a more elegant solution but it turned out to require an API change so I scrapped it.