<h1 align="center">ViewInspector 🕵️♂️ for SwiftUI</h1>
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 [](https://codecov.io/gh/nalexn/ViewInspector)
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**ViewInspector** is a library for unit testing SwiftUI views.
It allows for traversing a view hierarchy at runtime providing direct access to the underlying `View` structs.
## Why?
SwiftUI view is a function of state. We could provide it with the input but could not verify the output... Until now!
## Helpful links
* **[Inspection guide](guide.md)**
* **[SwiftUI API coverage](readiness.md)**
## Use cases
### 1. Search the view of a specific type or condition
Use one of the `find` functions to quickly locate a specific view or assert there are none of such:
```swift
try sut.inspect().find(button: "Back")
try sut.inspect().findAll(ViewType.Text.self,
where: { try $0.attributes().isBold() })
```
Check out [this section](guide.md#dynamic-query-with-find) in the guide for the reference.
### 2. Read the inner state of the standard views
Standard SwiftUI views are no longer a black box:
```swift
let sut = Text("Completed by \(72.51, specifier: "%.1f")%").font(.caption)
let string = try sut.inspect().text().string(locale: Locale(identifier: "es"))
XCTAssertEqual(string, "Completado por 72,5%")
XCTAssertEqual(try sut.inspect().text().attributes().font(), .caption)
```
Each view has its own set of inspectable parameters, you can refer to the [API coverage](readiness.md) document to see what's available for a particular SwiftUI view.
### 3. Verify your custom view's state
Obtain a copy of your custom view with actual state and references from the hierarchy of any depth:
```swift
let sut = try view.inspect().find(CustomView.self).actualView()
XCTAssertTrue(sut.viewModel.isUserLoggedIn)
```
The library can operate with various types of the view's state, such as `@Binding`, `@State`, `@ObservedObject` and `@EnvironmentObject`.
### 4. Trigger side effects
You can simulate user interaction by programmatically triggering system-control callbacks:
```swift
try sut.inspect().find(button: "Close").tap()
let list = try view.inspect().list()
try list[5].view(RowItemView.self).callOnAppear()
```
The library provides helpers for writing asynchronous tests for views with callbacks.
## FAQs
### Which views and modifiers are supported?
Check out the [API coverage](readiness.md).
### Is it using private APIs?
**ViewInspector** is using the official Swift reflection API to dissect the view structures. So it'll be production-friendly even if you could somehow ship the test target to the production.
### How do I add it to my Xcode project?
Assure you're adding the framework to your unit-test target. **Do NOT** add it to the main build target.
#### Swift Package Manager
`https://github.com/nalexn/ViewInspector`
#### Carthage
`github "nalexn/ViewInspector"`
#### CocoaPods
`pod 'ViewInspector'`
### How do I use it in my project?
Please refer to the [Inspection guide](guide.md). You can also check out my other [project](https://github.com/nalexn/clean-architecture-swiftui) that harnesses the **ViewInspector** for testing the entire UI.
### Contributions
Contributions are welcomed! If you see an unsupported view or modifier, you can either open an issue (so I could prioritize such SwiftUI APIs over the rest), or try to crack it yourself: use the `print("\(Inspector.print(<#view#>) as AnyObject)")` as the starting point of the investigation.