Gum gum-unit-tests

Reference guide for writing unit tests in the Gum repository. Load this when writing or modifying tests in Gum.ProjectServices.Tests, Gum.Cli.Tests, or any other Gum test project.

install

source · Clone the upstream repo

git clone https://github.com/vchelaru/Gum

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/vchelaru/Gum "$T" && mkdir -p ~/.claude/skills && cp -r "$T/.claude/skills/gum-unit-tests" ~/.claude/skills/vchelaru-gum-gum-unit-tests && rm -rf "$T"

manifest: .claude/skills/gum-unit-tests/SKILL.md

Gum Unit Test Reference

Test Projects

Project	Location	What it tests
`MonoGameGum.Tests`	`MonoGameGum.Tests/`	Default project for new tests. MonoGame runtime, Forms controls, rendering, localization, data types — anything not specific to V2/V3 visuals or integration
`Gum.ProjectServices.Tests`	`Tests/Gum.ProjectServices.Tests/`	Headless services: error checking, codegen, font generation, project loading
`Gum.Cli.Tests`	`Tests/Gum.Cli.Tests/`	CLI command exit codes and output
`MonoGameGum.Tests.V2`	`Tests/MonoGameGum.Tests.V2/`	Tests specific to V2 default visuals
`MonoGameGum.Tests.V3`	`Tests/MonoGameGum.Tests.V3/`	Tests specific to V3 default visuals
`MonoGameGum.IntegrationTests`	`Tests/MonoGameGum.IntegrationTests/`	Requires a real `GraphicsDevice` : content loading, renderer teardown, full `GumService` lifecycle

When in doubt, put tests in

MonoGameGum.Tests/

. Only use V2/V3 projects for tests that exercise visual-version-specific behavior.

Key Rules

Always use Shouldly — never xUnit
```
Assert
```
. Alphabetize test methods within a class.
Disable parallel execution in every test project (
```
[assembly: CollectionBehavior(DisableTestParallelization = true)]
```
) — Gum uses global singletons.
Use named parameters for boolean literals.

Headless Tests (ProjectServices, MonoGameGum.Tests.V2)

Read

BaseTestClass

before adding setup — it handles singleton init, a ready-made

GumProjectSave

, and

Dispose

cleanup. Don't repeat that in subclasses.

Every

StateSave

must have

ParentContainer

set —

GetValueRecursive

traverses via that field and silently misbehaves or throws when it is null. Use

ScreenSave

for standalone state tests (no base type, no StandardElementsManager fallback).

InternalsVisibleTo

is set up in

Gum.ProjectServices.csproj

for

Gum.ProjectServices.Tests

— internal members are directly accessible.

Integration Tests (MonoGameGum.IntegrationTests)

Use this project for anything requiring a real

GraphicsDevice

. Each test creates a minimal nested

Game

subclass, calls

game.RunOneFrame()

to trigger

Initialize

, then asserts. See

Tests/MonoGameGum.IntegrationTests/MonoGameGum/GumServiceUnitTests.cs

for the established pattern. Always call

LoaderManager.Self?.DisposeAndClear()

in the

Game.Dispose

override to prevent state leaking across tests via the singleton.