Same ghapi version returns different results depending on fastcore version (JSON `null` → empty `AttrDict`)

Start with the GhApi reproduction in the issue and compare the response conversion under fastcore 1.8.16 and 1.11.2, focusing on the reported fastcore.dict2obj processing. Done means GitHub JSON null values consistently remain Python None across the supported fastcore versions, with the behavior verified through the shown repository-list call.

Summary

When using the same ghapi version, the return value of API calls changes depending on the fastcore dependency version.
Specifically, JSON null values from the GitHub REST API (e.g. repository description) are returned as:

• None with fastcore==1.8.16
• empty fastcore.basics.AttrDict ({}) with fastcore==1.11.2
  This breaks the semantic meaning of the API response and causes downstream issues (e.g. database storage, business logic).

Why this is a problem

• GitHub API explicitly defines description: null as “no value”
• In Python, this should map to None
• {} (empty mapping) has a different semantic meaning than None
• The behavior changes without changing the ghapi version, only by upgrading a dependency

From a user’s perspective, this means:

The same ghapi version produces different API results depending on dependency resolution

This breaks API contract stability and reproducibility.

Environment

Component	Version
ghapi	1.0.8
fastcore (local)	1.8.16
fastcore (sam)	1.11.2
Python	3.10.19

Reproduction Code

from ghapi.core import GhApi

api = GhApi(token="*******", owner="ORG_NAME")

batch = api.repos.list_for_org("ORG_NAME", per_page=1, page=1)
r0 = batch[0]

print("item:", r0.get("description"), type(r0.get("description")))
print("attr:", r0.description, type(r0.description))
print("has key:", "description" in r0)

Actual Results

With fastcore==1.11.2

item: {} <class 'fastcore.basics.AttrDict'>
attr: {} <class 'fastcore.basics.AttrDict'>
has key: True

With fastcore==1.8.16

item: None <class 'NoneType'>
attr: None <class 'NoneType'>
has key: True

Expected Behavior

JSON null values from the GitHub API should consistently map to Python None, regardless of fastcore version.
At minimum, ghapi should:

• Preserve the semantic meaning of null
• Or pin / constrain fastcore versions to avoid silent behavior changes

Additional Notes

• The conversion appears to happen during fastcore.dict2obj processing
• ghapi currently forwards this behavior directly to users
• This is not a database or SQLAlchemy issue — the value is already {} immediately after the ghapi call

This behavior change is unexpected, breaking, and difficult to detect, especially in data ingestion pipelines.
I believe this is worth addressing either in ghapi itself or through tighter fastcore integration.
Thanks for your work on ghapi.