feat: iOS unit tests (#366)

## 📜 Description

Added native unit tests on iOS.

## 💡 Motivation and Context

### Where to write unit tests?

The problem with current integration of unit-tests on iOS is the fact
that we depends on `react` dependency heavily which is available in
`example` or `FabricExample` projects.

Of course I didn't want to duplicate tests (and there is no clear option
on how to add them for `KeyboardController.xcodeproj` i. e. root) so I
decided to create a new "HelloWorld" project and link files that I want
to test.

Fortunately current codebase is designed quite well (thanks for
supporting both architectures 😀), so I have a separated business-logic
(keyboard frame tracking etc.) and consumers (react views/bridge
bindings).

So I didn't make any modifications to the source code. The only one
"suspicious" thing is adding extension for `reactTag` property (I rely
on it in Extensions file and Extension file needs to be linked since
`ViewHierarchyNavigator` uses `UIResponder.current` extension).

### Unit tests approach

I decided to test everything as unit tests. Of course some of methods,
such as `becomeFirstResponder` doesn't work (actually they work, but
there is no way to check that method has been called as we can do in
jest - and by default iOS doesn't provide any mocks).

So I've created `TestableTextField`/`TestableTextView` and for hierarchy
creation used these classes.

Some of corresponding Android tests can not be ported to iOS:
- get all inputs -> relies on window usage, and actual window doesn't
contain any TextInputs -> most likely we need to pass params and pass a
mock from unit tests but I don't want to change source code right now
- testSetFocusToNextDoesNothingIfLastElement -> there is no way to check
that view keeps focus
- testSetFocusToPrevDoesNothingIfFirstElement -> there is no way to
check that view keeps focus

But overall I'm happy to have at least something to have a better
protection over accident changes that can break the library code.

### CI integration

Also I added a job on CI to run these tests continuously.

## 📢 Changelog

### CI
- added a job for running unit-tests;

### iOS

- added `KeyboardControllerNative` project;
- excluded `KeyboardControllerNative` from Pods (to prevent compilation
errors);

### JS

- excluded `KeyboardControllerNative` from being published to `npm`;

## 🤔 How Has This Been Tested?

Tested locally and on CI.

## 📝 Checklist

- [ ] CI successfully passed
- [x] I added new mocks and corresponding unit-tests if library API was
changed

.github/workflows/verify-ios.yml

@@ -54,3 +54,26 @@ jobs:
 
       - name: Verify formatting
         run: yarn lint-clang
+  unit-tests:
+    name: 📖 Unit tests
+    runs-on: macOS-14
+    defaults:
+      run:
+        working-directory: ./ios/KeyboardControllerNative
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: maxim-lobanov/setup-xcode@v1
+        with:
+          xcode-version: "15.3"
+
+      - name: Install xcpretty
+        run: gem install xcpretty
+
+      - name: Run unit tests
+        run: "set -o pipefail && xcodebuild \
+          test \
+          -scheme KeyboardControllerNative \
+          -only-testing KeyboardControllerNativeTests \
+          -destination 'platform=iOS Simulator,name=iPhone 15 Pro' \
+          CODE_SIGNING_ALLOWED=NO | xcpretty"

FabricExample/ios/Podfile.lock

@@ -1597,7 +1597,7 @@ SPEC CHECKSUMS:
   React-jsitracing: 4fed160d939e93a39049481f47744af246a7ac2c
   React-logger: 3eb80a977f0d9669468ef641a5e1fabbc50a09ec
   React-Mapbuffer: 84ea43c6c6232049135b1550b8c60b2faac19fab
-  react-native-keyboard-controller: 7d37211044d15aa8178b04df9a85263f52a07203
+  react-native-keyboard-controller: 779693f3474f963ee1d9df1d965368ba82c88abf
   react-native-safe-area-context: 1e374c51edf537be56313b893b6e96b0e254ddfe
   React-nativeconfig: b4d4e9901d4cabb57be63053fd2aa6086eb3c85f
   React-NativeModulesApple: cd26e56d56350e123da0c1e3e4c76cb58a05e1ee

example/ios/Podfile.lock

@@ -1405,7 +1405,7 @@ SPEC CHECKSUMS:
   React-jsinspector: 85583ef014ce53d731a98c66a0e24496f7a83066
   React-logger: 3eb80a977f0d9669468ef641a5e1fabbc50a09ec
   React-Mapbuffer: 84ea43c6c6232049135b1550b8c60b2faac19fab
-  react-native-keyboard-controller: 27a2f1da4a1fedf9f01bf49e2dcabba700daa284
+  react-native-keyboard-controller: e0f1b0b71a76e05c99fc6bfdd8b8ec05bead4105
   react-native-safe-area-context: b97eb6f9e3b7f437806c2ce5983f479f8eb5de4b
   react-native-text-input-mask: 22ca8eeef84d42a896f79428f7d175a5eb8b1c4e
   React-nativeconfig: b4d4e9901d4cabb57be63053fd2aa6086eb3c85f

ios/KeyboardControllerNative/KeyboardControllerNative/Assets.xcassets/AccentColor.colorset/Contents.json

@@ -0,0 +1,11 @@
+{
+  "colors": [
+    {
+      "idiom": "universal"
+    }
+  ],
+  "info": {
+    "author": "xcode",
+    "version": 1
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNative/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,13 @@
+{
+  "images": [
+    {
+      "idiom": "universal",
+      "platform": "ios",
+      "size": "1024x1024"
+    }
+  ],
+  "info": {
+    "author": "xcode",
+    "version": 1
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNative/Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info": {
+    "author": "xcode",
+    "version": 1
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNative/ContentView.swift

@@ -0,0 +1,24 @@
+//
+//  ContentView.swift
+//  KeyboardControllerNative
+//
+//  Created by Kiryl Ziusko on 29/03/2024.
+//
+
+import SwiftUI
+
+struct ContentView: View {
+  var body: some View {
+    VStack {
+      Image(systemName: "globe")
+        .imageScale(.large)
+        .foregroundStyle(.tint)
+      Text("Hello, world!")
+    }
+    .padding()
+  }
+}
+
+#Preview {
+  ContentView()
+}

ios/KeyboardControllerNative/KeyboardControllerNative/Extension+UIView.swift

@@ -0,0 +1,15 @@
+//
+//  Extension+UIView.swift
+//  Tests
+//
+//  Created by Kiryl Ziusko on 21/02/2024.
+//
+
+import Foundation
+import UIKit
+
+public extension UIView {
+  var reactTag: NSNumber {
+    return tag as NSNumber
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNative/KeyboardControllerNativeApp.swift

@@ -0,0 +1,17 @@
+//
+//  KeyboardControllerNativeApp.swift
+//  KeyboardControllerNative
+//
+//  Created by Kiryl Ziusko on 29/03/2024.
+//
+
+import SwiftUI
+
+@main
+struct KeyboardControllerNativeApp: App {
+  var body: some Scene {
+    WindowGroup {
+      ContentView()
+    }
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNative/Preview Content/Preview Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info": {
+    "author": "xcode",
+    "version": 1
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNativeTests/KeyboardControllerNativeTests.swift

@@ -0,0 +1,175 @@
+//
+//  KeyboardControllerNativeTests.swift
+//  KeyboardControllerNativeTests
+//
+//  Created by Kiryl Ziusko on 29/03/2024.
+//
+
+@testable import KeyboardControllerNative
+import XCTest
+
+extension XCTestCase {
+  func waitForFocusChange(
+    to textField: TestableInput,
+    timeout: TimeInterval = 10.0,
+    file: StaticString = #file,
+    line: UInt = #line
+  ) {
+    let expectation = XCTestExpectation(description: "Wait for focus change to \(textField.tag)")
+
+    XCTAssertFalse(
+      textField.becomeFirstResponderCalled,
+      "Expected focus shouldn't be initially set for tag \(textField.tag)"
+    )
+
+    DispatchQueue.main.async {
+      XCTAssertTrue(
+        textField.becomeFirstResponderCalled,
+        "Expected focus to be set to text field with tag \(textField.tag)",
+        file: file,
+        line: line
+      )
+      expectation.fulfill()
+    }
+
+    wait(for: [expectation], timeout: timeout)
+  }
+}
+
+protocol TestableInput: UIView, TextInput {
+  var becomeFirstResponderCalled: Bool { get set }
+  func becomeFirstResponder() -> Bool
+}
+
+class TestableTextField: UITextField, TestableInput {
+  var becomeFirstResponderCalled = false
+
+  override func becomeFirstResponder() -> Bool {
+    becomeFirstResponderCalled = true
+    return super.becomeFirstResponder()
+  }
+}
+
+class TestableTextView: UITextView, TestableInput {
+  var becomeFirstResponderCalled = false
+
+  override func becomeFirstResponder() -> Bool {
+    becomeFirstResponderCalled = true
+    return super.becomeFirstResponder()
+  }
+}
+
+final class KeyboardControllerNativeTests: XCTestCase {
+  var rootView: UIView!
+  var textFields: [TestableInput]!
+
+  override func setUpWithError() throws {
+    super.setUp()
+
+    rootView = UIView()
+    textFields = (1 ... 13).map { tag in
+      let textField = (tag % 2 == 0 ? TestableTextField() : TestableTextView()) as TestableInput
+      textField.tag = tag
+      let isEditable = tag != 3 && tag != 4 // Assuming ids 3 and 4 are not editable, similar to our Android test
+      (textField as? UITextField)?.isEnabled = isEditable
+      (textField as? UITextView)?.isEditable = isEditable
+
+      return textField
+    }
+
+    let subView = UIView()
+    for (index, textField) in textFields.enumerated() {
+      if index == 4 {
+        rootView.addSubview(subView)
+      }
+      if index >= 4, index <= 6 {
+        subView.addSubview(textField)
+      } else {
+        rootView.addSubview(textField)
+      }
+    }
+  }
+
+  override func tearDownWithError() throws {
+    // Put teardown code here. This method is called after the invocation of each test method in the class.
+  }
+
+  func testSetFocusToNextShouldSetFocusToNextField() throws {
+    let textInput1 = textFields[0]
+    FocusedInputHolder.shared.set(textInput1)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "next")
+
+    waitForFocusChange(to: textFields[1])
+  }
+
+  func testSetFocusToPrevShouldSetFocusToPreviousField() throws {
+    let textInput2 = textFields[1]
+    FocusedInputHolder.shared.set(textInput2)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "prev")
+
+    waitForFocusChange(to: textFields[0])
+  }
+
+  func testSetFocusToNextShouldSkipNonEditableFields() throws {
+    let textInput2 = textFields[1]
+    FocusedInputHolder.shared.set(textInput2)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "next")
+
+    waitForFocusChange(to: textFields[4])
+  }
+
+  func testSetFocusToPrevShouldSkipNonEditableFields() throws {
+    let textInput5 = textFields[4]
+    FocusedInputHolder.shared.set(textInput5)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "prev")
+
+    waitForFocusChange(to: textFields[1])
+  }
+
+  func testSetFocusToNextWithinGroup() throws {
+    let textInput5 = textFields[4]
+    FocusedInputHolder.shared.set(textInput5)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "next")
+
+    waitForFocusChange(to: textFields[5])
+  }
+
+  func testSetFocusToPrevWithinGroup() throws {
+    let textInput6 = textFields[5]
+    FocusedInputHolder.shared.set(textInput6)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "prev")
+
+    waitForFocusChange(to: textFields[4])
+  }
+
+  func testSetFocusToNextExitsGroup() throws {
+    let textInput7 = textFields[6]
+    FocusedInputHolder.shared.set(textInput7)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "next")
+
+    waitForFocusChange(to: textFields[7])
+  }
+
+  func testSetFocusToPrevEntersGroupAtLastElement() throws {
+    let textInput8 = textFields[7]
+    FocusedInputHolder.shared.set(textInput8)
+
+    ViewHierarchyNavigator.setFocusTo(direction: "prev")
+
+    waitForFocusChange(to: textFields[6])
+  }
+
+  func testPerformanceExample() throws {
+    // This is an example of a performance test case.
+    measure {
+      // Put the code you want to measure the time of here.
+    }
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNativeUITests/KeyboardControllerNativeUITests.swift

@@ -0,0 +1,41 @@
+//
+//  KeyboardControllerNativeUITests.swift
+//  KeyboardControllerNativeUITests
+//
+//  Created by Kiryl Ziusko on 29/03/2024.
+//
+
+import XCTest
+
+final class KeyboardControllerNativeUITests: XCTestCase {
+  override func setUpWithError() throws {
+    // Put setup code here. This method is called before the invocation of each test method in the class.
+
+    // In UI tests it is usually best to stop immediately when a failure occurs.
+    continueAfterFailure = false
+
+    // In UI tests it’s important to set the initial state - such as interface orientation,
+    // which required for your tests before they run. The setUp method is a good place to do this.
+  }
+
+  override func tearDownWithError() throws {
+    // Put teardown code here. This method is called after the invocation of each test method in the class.
+  }
+
+  func testExample() throws {
+    // UI tests must launch the application that they test.
+    let app = XCUIApplication()
+    app.launch()
+
+    // Use XCTAssert and related functions to verify your tests produce the correct results.
+  }
+
+  func testLaunchPerformance() throws {
+    if #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 7.0, *) {
+      // This measures how long it takes to launch your application.
+      measure(metrics: [XCTApplicationLaunchMetric()]) {
+        XCUIApplication().launch()
+      }
+    }
+  }
+}

ios/KeyboardControllerNative/KeyboardControllerNativeUITests/KeyboardControllerNativeUITestsLaunchTests.swift

@@ -0,0 +1,32 @@
+//
+//  KeyboardControllerNativeUITestsLaunchTests.swift
+//  KeyboardControllerNativeUITests
+//
+//  Created by Kiryl Ziusko on 29/03/2024.
+//
+
+import XCTest
+
+// swiftlint:disable:next type_name
+final class KeyboardControllerNativeUITestsLaunchTests: XCTestCase {
+  override class var runsForEachTargetApplicationUIConfiguration: Bool {
+    true
+  }
+
+  override func setUpWithError() throws {
+    continueAfterFailure = false
+  }
+
+  func testLaunch() throws {
+    let app = XCUIApplication()
+    app.launch()
+
+    // Insert steps here to perform after app launch but before taking a screenshot,
+    // such as logging into a test account or navigating somewhere in the app
+
+    let attachment = XCTAttachment(screenshot: app.screenshot())
+    attachment.name = "Launch Screen"
+    attachment.lifetime = .keepAlways
+    add(attachment)
+  }
+}