Fix nullable struct fields defaulting to zero instead of null.

[mcdubhghlas]

Fixes #1379

Summary by CodeRabbit

• Bug Fixes

  • Nullable typed fields in GDScript structs now default to an uninitialized value rather than the type’s zero value.
  • Nullable fields with explicit defaults continue to use those specified values.

• Tests

  • Added runtime coverage for nullable fields across several supported types.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Team

Run ID: 49e53020-247a-4dd5-b975-c96d515b7af6

📥 Commits

Reviewing files that changed from the base of the PR and between b759f20 and 64c2b07.

⛔ Files ignored due to path filters (1)

• modules/gdscript/tests/scripts/runtime/features/struct_nullable_field_defaults.out is excluded by !**/*.out

📒 Files selected for processing (2)

• modules/gdscript/gdscript_analyzer.cpp
• modules/gdscript/tests/scripts/runtime/features/struct_nullable_field_defaults.gd

Included review availability: Your plan provides up to 8 included reviews per hour; 7 remain after this review.

---

Walkthrough

The GDScript analyzer now assigns null Variant defaults to nullable struct fields instead of type zero values. A runtime test covers nullable fields, non-nullable fields, and an explicit nullable default.

Changes

Nullable struct defaults

Layer / File(s)	Summary
Default generation and runtime validation modules/gdscript/gdscript_analyzer.cpp, modules/gdscript/tests/scripts/runtime/features/struct_nullable_field_defaults.gd	The analyzer excludes nullable fields from automatic zero-value construction. The runtime test checks nullable int, Vector2, and Vector3 fields, a non-nullable int, and an explicit nullable default of 5.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to cffab

Nullable GDScript struct fields now default to null while non-nullable and explicitly initialized fields retain their intended values. The change is ready to merge.

Suggested reviewers: arctis-fireblight, generalprotectionfault

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files. (1 skipped: 1 …	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: nullable struct fields now default to null instead of zero values.

Full details: Docstring Coverage

Explanation

Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files. (1 skipped: 1 unsupported.)

• Fix all pre-merge checks with AI

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[Arctis-Fireblight]

LGTM