GlobalGameJame/Library/PackageCache/com.unity.test-framework@1.1.9/Documentation~/reference-custom-constraints.md

32 lines
1.3 KiB
Markdown
Raw Normal View History

2020-01-31 15:10:04 +00:00
# Custom constraints
`NUnit` allows you to write test assertions in a more descriptive and human readable way using the [Assert.That](https://github.com/nunit/docs/wiki/Assertions) mechanism, where the first parameter is an object under test and the second parameter describes conditions that the object has to meet.
## Is
Weve extended `NUnit` API with a custom constraint type and declared an overlay `Is` class. To resolve ambiguity between the original implementation and the custom one you must explicitly declare it with a using statement or via addressing through the full type name `UnityEngine.TestTools.Constraints.Is`.
### Static Methods
| Syntax | Description |
| -------------------- | ------------------------------------------------------------ |
| `AllocatingGCMemory` | A constraint type that invokes the delegate you provide as the parameter of `Assert.That` and checks whether it causes any GC memory allocations. It passes if any GC memory is allocated and fails if not. |
## Example
```c#
using Is = UnityEngine.TestTools.Constraints.Is;
class MyTestClass
{
[Test]
public void MyTest()
{
Assert.That(() => {
var i = new int[500];
}, Is.AllocatingGCMemory());
}
}
```