[TRACKER] Unit tests to add or improve

[Calinou]

Our unit test coverage is currently fairly low. We'd like to increase our unit test coverage; any help is welcome.

Interested in writing new unit tests? See the unit tests documentation and compiling instructions.
If you have further questions, join the Godot Contributors Chat.

When opening a pull request, please link back to this issue (#43440) in the PR description so that we can keep track of it more easily.

If you have the appropriate permissions, feel free to edit this issue to add new items or check items for which a PR has been opened.

Classes to test

These classes are currently lacking in test coverage, and are therefore highest-priority for receiving unit tests. Deprecated classes are not listed.

Note

When a class is listed with "and" along a given list item, it should be submitted in the same pull request whenever possible. Tests for these classes can be in the same file or a different file depending on the size and complexity of the test suite. If in doubt, follow the file organization used in the original class implementation.

• AnimationPlayer Add tests for AnimationPlayer #92649
• AudioStreamInteractive (and AudioStreamPlaybackInteractive, AudioStreamPlaylist, AudioStreamSynchronized)
• BaseButton (and Button) Add button unit test #93381
• Control: Test sizing, anchors and container logic by checking control position and size after creating an UI layout. Test focus neighbor behavior using simulated input events (ui_focus_ actions). This class is complex, so tests for it can be split in multiple pull requests.
• Decal Add unit tests for Decal #93463
• ENetConnection (and ENetPacketPeer)
• FontFile
• FontVariation
• GLTFDocument (and GLTFState)
• HeightMapShape3D Add unit tests for HeightMapShape3D #95123
• HTTPRequest
• ImageTexture3D Add unit test cases for ImageTexture3D #91233
• Node2D Add unit tests for Node2D helper methods #91654
• Node3D Add unit test for Node3D #97143
• Occluder3D (and ArrayOccluder3D, BoxOccluder3D, PolygonOccluder3D, QuadOccluder3D, and SphereOccluder3D)
• OccluderInstance3D: Test its baking functionality using bake_scene() and/or bake_single_node(). These methods are not currently exposed to the scripting API, but they're still public methods.
• OptimizedTranslation Currently being worked on by @SommAid
• OptionButton Add unit tests for OptionButton #93824
• PacketPeer
• Parallax2D
• PhysicsMaterial Currently being worked on by @D0V4HKIIN
• ReflectionProbe: Run various setters/getters then check get_aabb().
• Sky
• StandardMaterial3D (and ORMMaterial3D)
• StreamPeerTCP
• StreamPeerTLS
• StreamPeerGZIP
• StreamPeerBuffer
• StyleBoxFlat Currently being worked on by @mshojatalab
• StyleBoxLine (and StyleBoxEmpty) Currently being worked on by @rcooper47
• StyleBoxTexture Add unit tests for StyleBoxTexture #95218
• Timer
• WebSocketPeer
• VisibleOnScreenNotifier2D: May not be testable in headless mode, but it's worth trying.
• VisibleOnScreenNotifier3D: May not be testable in headless mode, but it's worth trying.

Completed classes

These classes currently have good test coverage. Further improvements may be possible by testing methods that were added after the tests were merged.

• AABB Add a test suite for AABB #43727
• Animation Add a unit test suite for Animation #57490
• Array Add a test suite for Array #46227
• ArrayMesh
• AudioStreamWAV Add test cases for AudioStreamWAV #60736
• BitMap
• Camera2D Add unit tests for Camera2D #88614
• Camera3D: May not be testable in headless mode, but it's worth trying. Test is_position_behind() and the project_/unproject_ methods in particular
• CryptoKey Add unit tests for CryptoKey #89021
• Curve Add a test suite for Curve #43516
• Curve2D Add unit tests for Curve2D #71308
• Curve3D Add unit tests for Curve3D #76812
• Dictionary Add a test suite for Dictionary #47511
• FastNoiseLite
• Font Added getter tests for dynamic fonts #81503
• GDScript Add a unit test suite for GDScript #48657
• Geometry2D Add extra unit tests for Geometry2D #59643
• Geometry3D Initial tests for geometry3D  #44974
• GradientTexture Add unit tests for GradientTexture1D and GradientTexture2D #90501
• HashingContext Add unit tests for HashingContext #43459
• HTTPClient Add HTTPClient unit tests #76636
• Image Add a test suite for the Image class #45737
• ImageTexture Add ImageTexture unit tests #88044
• InputEvent Add a test suite to InputEvent #79444
• InputEventKey Add Unit Tests for InputEventKey #59193
• JSON Add a test suite for JSON #43517
• JSONRPC: Add unit tests for JSONRPC #89124
• Math Add a test suite for Math:: namespace functions #48721
• Marshalls Marshall core unit tests #44797
• Node: Initial tests for node #70152 More Node tests #71367
• NodePath Add a test suite for NodePath #43578
• NoiseTexture Add tests for FastNoiseLite/NoiseTexture #70919
• Object Add a test suite for Object #43583 (completed by More object unit tests #44387)
• OS Add a test suite for OS #42069
• PackedScene Add unit tests for PackedScene #79440 Improve PackedScene unit test for complex scene #80423 Improve PackedScene unit test by covering more methods #80819
• Path2D Unit tests for Path2D class #66927
• PathFollow2D PathFollow2D unit test  #46277
• Path3D
• PathFollow3D add PathFollow3D unit test #46341
• PCKPacker Add a test suite for PCKPacker #43572
• Plane Added a test suite for the Plane object. #44492
• PrimitiveMesh (CapsuleMesh, CubeMesh, …)
• Projection Add a test suite for Projection #77275
• Quaternion Add tests file for Quaternion unit tests, with initial UTs #50907
• RandomNumberGenerator Add unit tests for RandomNumberGenerator #44560
• Rect2: Not covered in the legacy math test. Add a test suite for Rect2 and Rect2i #43514
• Rect2i: Not covered in the legacy math test. Add a test suite for Rect2 and Rect2i #43514
• RegEx Adds additional tests for RegEx class #82225
• RID Add unit tests for RID class. #54325
• Resource Add a test suite for Resource #43731
• Shortcut Add unit tests for Shortcut #58712
• SpriteFrames unit tests for all public methods in the sprite frame class #57742
• Transform
• Transform2D
• Translation Add a test suite for Translation #48778
• TranslationServer Add a test suite for TranslationServer #79331
• Variant Add unit tests for Variant for operator overloading #76244
• Vector Add a test suite for Vector #48821
• Vector2/Vector2i Add test suite for Vector2 #47202
• Vector3/Vector3i Add test suite for Vector3 #48063
• Vector4/Vector4i Vector4/Vector4i: Add missing methods and tests #64027
• VisualShader Add unit test for VisualShader #70396

Non-testable classes

These classes can't be unit-tested for technical reasons. Unit tests always run in headless mode, so they can't do things such as rendering scenes and checking the visual result.

• CubeMap: Not testable without RenderingServer access.
• Shader: Not testable without RenderingServer access.

[ghost]

Hi me and a friend would like to take up some of these unit tests for a class project we have. Is there someone we can stay in touch with if we have questions? @Calinou

[Calinou]

@singher Thanks for your interest in contributing! I recommend joining the #godotengine-devel IRC channel on Freenode so you can ask development-related questions if needed.

I also recommend writing a comment here when you're starting to write tests for one class. This way, we can avoid stepping on each other's toes.

[ghost]

@Calinou perfect! Thank you so much for this opportunity. We will try our best to cover as many of those classes to test.

[ghost]

@Calinou Hi, I am working with @singher on this. We just wanted to let you know that we were planning on writing test cases for the following classes: Array, Dictionary, Node, RandomNumberGenerator.

[Xrayez]

we were planning on writing test cases for the following classes: Array, Dictionary, Node, RandomNumberGenerator.

@vinayakmtiwari RandomNumberGenerator initial test suite is written in #43103 and #43343 for new (not yet merged) functionality, so I guess you could take it as a base.

[maxmutant]

I would like to tackle some of the test cases too and would start with the classes HashingContext and RegEx.
Do you prefer separate PRs for each class, or should I aggregate them?

Ps.: First time contributor here!

[Xrayez]

@MaxMutantMayer it's better to create separate PRs for each class, this eases the review process → potentially speeds up the merging process. 😉

Also, I'd focus on one thing at a time.

[maxmutant]

@Xrayez Alright, makes sense. Thanks for clarification ☺️

[jonbonazza]

Noting for posterity that @Calinou found several issues with the JSON facilities not conforming to the spec. He purposely left these unit tests out of the PR to not confuse people, but I created a proposal to address this: godotengine/godot-proposals#1833

[Gorgonx7]

Hey if you don't mind I'm gonna take a crack at testing geometry 3D, it's also my first time contributing too :D

[Xrayez]

I had to write initial test suite for RandomNumberGenerator in #44089 with test cases for reproducibility, but not all public methods are currently tested.

[rmarco3e8]

Hello, I'm also looking to start contributing and am writing tests for Path2D. If someone has already been working on that class, let me know. Thanks for the resources dropped earlier. I'll be sure to ask any questions in the Freenode channel.

[cabinboy1031]

I am going to see about writing unit tests for the Plane class. Though this is my first contribution to anything in Github. If someone more experienced than me ends up wanting to do the unit tests go ahead as mine will probably not be the best and will most likely need to be improved after i am done with it anyways.

[ghost]

Hey @Calinou, I added some unit test cases for the Random Number Generator class in [#44350 ]. Also, I would like to remove my name and @singher from contributors to the Node class

[rmarco3e8]

Hey, I opened another PR for Object with a few more test cases in #44387.

[a-ivanov]

Hi there! I want to make my first time contribution to the project by writing unit tests for marshalls.h functions.
This one has not been covered yet, has it?

[Calinou]

Hi there! I want to make my first time contribution to the project by writing unit tests for marshalls.h functions.
This one has not been covered yet, has it?

Nobody has started work on testing Marshalls yet, but I haven't been able to access that class from C++ since it's mostly intended to be used from GDScript. It might not be easy to test.

[Xrayez]

I think it should be possible to test in either case, because core singletons are initialized in the test environment, I don't know exactly what might be a limitation for doing so.

For _Marshalls in core_bind.h you may just need to use _Marshalls::get_singleton()->variant_to_base64()... etc, but again not sure whether bind classes have to be tested currently, I think it may be better to test core stuff, which may be even easier to do if core doesn't rely on ClassDB functionality (those classes which expand GDCLASS macro), and just rely on pure data manipulation, which should be the case for marshalls I presume.

[a-ivanov]

Nobody has started work on testing Marshalls yet, but I haven't been able to access that class from C++ since it's mostly intended to be used from GDScript. It might not be easy to test.

Actually I thought about the strategy suggested by @Xrayez:

1. start with testing global functions in marshalls.h: encode_uint16, encode_uint32, etc. - first PR,
2. test _Marshalls class (need additional research on how to approach it, start with what @Xrayez wrote) - another PR.

Anyway, gonna ask you details later here/in Freenode channel.

Thanks.

[BrooklynWelsh]

Hello everyone, interested in making my first contribution with tests for the Node class. I've written a couple simple tests so far, have a question or two for the Freenode channel, but going well so far. Just wanted to comment to make sure it's not being worked on.

[Xrayez]

Since we talk about Node classes, I think it's also possible to simulate _process() calls with
node->notification(NOTIFICATION_PROCESS), or even propagate_notification(), for those classes which are supposed to be added to the scene tree (most of them)... Process notification are done in a main loop I presume, and current test environment has no SceneTree instantiated. It may also be possible to instantiate SceneTree manually (and this will likely reveal some hidden bugs).

Those are just some considerations if someone hadn't have much luck with testing Node derived classes yet...

[pafuent]

@Calinou Can I get some reviews on Unit Tests PRs?
#95590
#95784
#95931
#97262
#97311