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Merged
merged 1 commit into from
Feb 25, 2025
Merged

Rename test scoping trait #344

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57 changes: 0 additions & 57 deletions Sources/Dependencies/Documentation.docc/Articles/Testing.md
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Expand Up @@ -153,63 +153,6 @@ class FeatureTests: XCTestCase {
}
```


<!--
## Altered execution contexts

It is possible to completely alter the execution context in which a feature's logic runs, which is
great for tests. It means your feature doesn't need to actually make network requests just to test
how your feature deals with data returned from an API, and your feature doesn't need to interact
with the file system just to test how data gets loaded or persisted.

The tool for doing this is ``withDependencies(_:operation:)``, which allows you to specify
which dependencies should be overridden for the test, and then construct your feature's model in
that context:

```swift
@Test
func feature() async {
let model = withDependencies {
$0.continuousClock = .immediate
$0.date.now = Date(timeIntervalSince1970: 1234567890)
} operation: {
FeatureModel()
}

// Call methods on `model` and make assertions
}
```

As long as all of your dependencies are declared with `@Dependency` as instance properties on
`FeatureModel`, its entire execution will happen in a context in which any reference to
`continuousClock` is an `ImmediateClock` and any reference to `date.now` will always report that
the date is "Feb 13, 2009 at 3:31 PM".

> Note: If you are using XCTest it is important to note that if `FeatureModel` creates _other_
> models inside its methods, then it has to be careful about how it does so. In order for
> `FeatureModel`'s dependencies to propagate to the new child model, it must construct the child
> model in an altered execution context that passes along the dependencies. The tool for this is
> ``withDependencies(from:operation:fileID:filePath:line:column:)`` and can be used simply like
> this:
>
> ```swift
> @Observable
> class FeatureModel {
> // ...
>
> func buttonTapped() {
> self.child = withDependencies(from: self) {
> ChildModel()
> }
> }
> }
> ```
>
> This guarantees that when `FeatureModel`'s dependencies are overridden in tests that it will also
> trickle down to `ChildModel`.

-->

## Changing dependencies during tests

While it is most common to set up all dependencies at the beginning of a test and then make
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4 changes: 2 additions & 2 deletions Sources/DependenciesTestSupport/TestTrait.swift
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Expand Up @@ -5,7 +5,7 @@

#if swift(>=6.1)
@_documentation(visibility: private)
public struct _DependenciesScopeTrait: TestScoping, TestTrait, SuiteTrait {
public struct _DependenciesTrait: TestScoping, TestTrait, SuiteTrait {
let updateValues: @Sendable (inout DependencyValues) throws -> Void

@TaskLocal static var isRoot = true
Expand All @@ -29,7 +29,7 @@
}
}

extension Trait where Self == _DependenciesScopeTrait {
extension Trait where Self == _DependenciesTrait {
/// A trait that quarantines a test's dependencies from other tests.
///
/// When applied to a `@Suite` (or `@Test`), the dependencies used for that suite (or test)
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