core_schema.union_schema (and possibly others) create schemas with incorrect types

[dmontagu]

Despite this type annotation:

pydantic-core/pydantic_core/core_schema.py

Line 1751 in 9499441

choices: Required[List[CoreSchema]]

Using the core_schema.union_schema produces a schema with type(schema['choices']) is tuple:

from pydantic_core import core_schema

schema = core_schema.union_schema(core_schema.int_schema(), core_schema.str_schema())
print(schema['choices'])
# ({'type': 'int'}, {'type': 'str'})

I haven't checked, but I wouldn't be surprised if this behavior was consistent across other functions using the *args syntax to accept multiple items.

[adriangb]

I saw this once before and couldn’t figure out why it was happening. Glad you spotted it! I’ll make a PR, hopefully tonight.