Fix commented out tests in serializers.test_data

[Tim Graham]

tests/serializers/test_data.py contains some commented out items in the test_data list. I think it may be because not all serializers support those items. If this is the case, we should make appropriate modifications so the tests are run where they are supported and skipped where not.

[Baptiste Mispelon]

While looking into this, I believe I found the reason why some of the tests are commented: ​https://github.com/django/django/blob/8d6953d55c3aba04bbaf0f268499d6e405c653ff/tests/serializers_regress/models.py#L168-L170

The comment is not completely correct however because a few of the commented out models trigger and error immediately, regardless of the backend (TypeError: 'primary_key' is not a valid argument for ...).

• FilePKData, ImagePKData and NullBooleanPKData can be deleted because of this.

• DatePKData, DateTimePKData, TimePKData and TextPKData might be database-dependent (they all work under sqlite).

• Test case 51 (FileData) might be worth looking into a bit deeper. It fails when uncommented and I believe it might be caused by the weird FileField.__eq__ implementation.

[Claude Paroz]

FileField and NULL value issue is tracked in #10244.

[Claude Paroz <claude@…>]

In d02fc8d:

Refs #21286 -- Enabled serializer tests with date/datetime pk model

[Claude Paroz <claude@…>]

In 01c6a3e:

Refs #21286 -- Enabled serializer tests with time pk model

[Florian Apolloner]

@claude Your latest commit caused quite a few failures, did you forget to commit some code?

[Claude Paroz]

Argh, sorry! I was fooled by the fact the missing YAML lib in my test virtualenv wasn't showing by a skipped ('s') test. I will revert ASAP and try to work on that skip issue.

[Claude Paroz <claude@…>]

In 256182c4:

Revert "Refs #21286 -- Enabled serializer tests with time pk model"

This reverts commit 01c6a3e227b645e8dea97e9befecd23d1d3b8581.
Unfortunately, the YAML serializer is not yet able to cope with time values.

[Claude Paroz]

Missing skip issue in #28610.

[Adam Zapletal]

I started looking at this ticket today to see if it was still valid and submitted a small PR removing what I believe are some invalid commented-out test cases.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 3d4fe39b:

Refs #21286 -- Removed invalid commented out models and tests from serializer tests.

FileField/ImageField cannot be primary keys, so serialization support
for this case will not be implemented.

XMLField was removed in d1290b5b43485c7018ba92981d34c1f96614924e.

[Adam Zapletal]

I opened a PR uncommenting and adding a fix for TimePKData.

[Sarah Boyce <42296566+sarahboyce@…>]

In b9aa323:

Refs #21286 -- Fixed YAML serialization of TimeField primary key.

Handling for PyYAML not being able to serialize datetime.time
values is moved from handle_field to _value_from_field as only
non-primary key, non-relation fields are passed into handle_field.

[Adam Zapletal]

I opened a PR uncommenting and adding a fix for TextPKData.