Add type validation for foreign key and one to one model consistency

[Abdeldjalil-H]

Added validation to ensure consistency between the foreign key's expected model type and the actual model instance being assigned. This addresses an issue where mismatched model types could lead to silent failures or confusing database errors.

Description

Key changes:

1. Added type checking in Model._set_kwargs() when setting foreign key values
2. Raises a ValidationError with a clear error message when type mismatch occurs
3. Uses type() is comparison to ensure exact type matching (not allowing inheritance)

Motivation and Context

This fixes issue #1791 where inconsistencies between ForeignKeyField model parameter and actual model types were not caught.

How Has This Been Tested?

Running tests.

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added the changelog accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[henadzit]

@Abdeldjalil-H thank you for the PR!

A few comments:

• We need to add tests demonstrating that the check works
• Is the new check covers the case where the field is set to the model, e.g. instance.relation = relation? If not, this PR should add it.

[Abdeldjalil-H]

@henadzit thank you for your comments. I'll work on that.

Btw do you think we should use isinstance or is it okay to use the exact type comparison?

[henadzit]

Btw do you think we should use isinstance or is it okay to use the exact type comparison?

I think either will work since Tortoise only supports abstract class inheritance.

[henadzit]

@Abdeldjalil-H thank you for great work! I left a few more comments, please have a look!

[henadzit]

There is an issue with CHANGELOG formatting and CI is failing. Apart from that the changes look good to me!

[henadzit]

Formatting doesn't look correct here.

[Abdeldjalil-H]

I don't know if the tests are failing because of the changes or other things. Is the database cleared after each test case? @henadzit

[henadzit]

I don't know if the tests are failing because of the changes or other things. Is the database cleared after each test case? @henadzit

The test cases that are failing are based on test.TestCase which is using transactions to isolate tests. I have a hunch that your changes have an unexpected side effect that lead to these failures.

[henadzit]

@Abdeldjalil-H can you please rebase your changes and correct the CHANGELOG? I improved test isolation in #1816, maybe, it will resolve issues in this PR.

[coveralls]

Pull Request Test Coverage Report for Build 12412674345

Details

• 13 of 14 (92.86%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 90.143%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tortoise/models.py	12	13	92.31%

Totals
Change from base Build 12410555131:	0.003%
Covered Lines:	6381
Relevant Lines:	6963

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💛 - Coveralls