Re: [PATCH v4 11/14] qapi/introspect.py: add type hint annotations

[Markus Armbruster <armbru@redhat.com>]

John Snow <jsnow@redhat.com> writes:

> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  scripts/qapi/introspect.py | 115 ++++++++++++++++++++++++++-----------
>  scripts/qapi/mypy.ini      |   5 --
>  scripts/qapi/schema.py     |   2 +-
>  3 files changed, 82 insertions(+), 40 deletions(-)
>
> diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
> index 60ec326d2c7..b7f2a6cf260 100644
> --- a/scripts/qapi/introspect.py
> +++ b/scripts/qapi/introspect.py
> @@ -30,10 +30,19 @@
>  )
>  from .gen import QAPISchemaMonolithicCVisitor
>  from .schema import (
> +    QAPISchema,
>      QAPISchemaArrayType,
>      QAPISchemaBuiltinType,
> +    QAPISchemaEntity,
> +    QAPISchemaEnumMember,
> +    QAPISchemaFeature,
> +    QAPISchemaObjectType,
> +    QAPISchemaObjectTypeMember,
>      QAPISchemaType,
> +    QAPISchemaVariant,
> +    QAPISchemaVariants,
>  )
> +from .source import QAPISourceInfo
>  
>  
>  # This module constructs a tree data structure that is used to
> @@ -57,6 +66,8 @@
   # generate the introspection information for QEMU. It behaves similarly
   # to a JSON value.
   #
   # A complexity over JSON is that our values may or may not be annotated.
   #
   # Un-annotated values may be:
   #     Scalar: str, bool, None.
   #     Non-scalar: List, Dict
   # _value = Union[str, bool, None, Dict[str, TreeValue], List[TreeValue]]
   #
   # With optional annotations, the type of all values is:
   # TreeValue = Union[_value, Annotated[_value]]
   #
   # Sadly, mypy does not support recursive types, so we must approximate this.
   _stub = Any
   _scalar = Union[str, bool, None]
   _nonscalar = Union[Dict[str, _stub], List[_stub]]
>  _value = Union[_scalar, _nonscalar]
>  TreeValue = Union[_value, 'Annotated[_value]']
>  
> +# This is a (strict) alias for an arbitrary object non-scalar, as above:
> +_DObject = Dict[str, object]

Sounds greek :)

It's almost the Dict part of _nonscalar, but not quite: object vs. Any.

I naively expect something closer to

   _scalar = ...
   _object = Dict[str, _stub]
   _nonscalar = Union[_object, List[_stub]

and (still naively) expect _object to be good enough to serve as type
annotation for dicts representing JSON objects.

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