Allow .introspectTabBarController() on TabView directly

CHANGELOG.md

@@ -4,6 +4,7 @@ Changelog
 ## master
 
  - Allow `.introspectNavigationController()` on NavigationView directly.
+ - Allow `.introspectTabBarController()` on TabView directly.
 
 ## [0.0.4]
 

Introspect/Introspect.swift

@@ -85,6 +85,30 @@ public enum Introspect {
         return nil
     }
     
+    /// Finds a previous sibling that is a view controller of the specified type.
+    /// This method does not inspect siblings recursively.
+    /// Returns nil if no sibling is of the specified type.
+    public static func previousSibling<AnyViewControllerType: UIViewController>(
+        ofType type: AnyViewControllerType.Type,
+        from entry: UIViewController
+    ) -> AnyViewControllerType? {
+        
+        guard let parent = entry.parent,
+            let entryIndex = parent.children.firstIndex(of: entry),
+            entryIndex > 0
+        else {
+            return nil
+        }
+        
+        for child in parent.children[0..<entryIndex].reversed() {
+            if let typed = child as? AnyViewControllerType {
+                return typed
+            }
+        }
+        
+        return nil
+    }
+    
     /// Finds a next sibling that contains a view of the specified type.
     /// This method inspects siblings recursively.
     /// Returns nil if no sibling contains the specified type.
@@ -337,7 +361,16 @@ extension View {
     /// Finds a `UITabBarController` from any SwiftUI view embedded in a `SwiftUI.TabView`
     public func introspectTabBarController(customize: @escaping (UITabBarController) -> ()) -> some View {
         return inject(IntrospectionViewController(
-            selector: { $0.tabBarController },
+            selector: { introspectionViewController in
+                
+                // Search in ancestors
+                if let navigationController = introspectionViewController.tabBarController {
+                    return navigationController
+                }
+                
+                // Search in siblings
+                return Introspect.previousSibling(ofType: UITabBarController.self, from: introspectionViewController)
+            },
             customize: customize
         ))
     }

IntrospectTests/IntrospectTests.swift

@@ -45,6 +45,20 @@ private struct TabTestView: View {
     }
 }
 
+private struct TabRootTestView: View {
+    @State private var selection = 0
+    let spy: () -> Void
+    var body: some View {
+        TabView {
+            Text("Item 1")
+                .tag(0)
+        }
+        .introspectTabBarController { _ in
+            self.spy()
+        }
+    }
+}
+
 private struct ListTestView: View {
     
     let spy1: () -> Void
@@ -176,6 +190,16 @@ class IntrospectTests: XCTestCase {
         wait(for: [expectation], timeout: 1)
     }
     
+    func testTabViewRoot() {
+        
+        let expectation = XCTestExpectation()
+        let view = TabRootTestView(spy: {
+            expectation.fulfill()
+        })
+        TestUtils.present(view: view)
+        wait(for: [expectation], timeout: 1)
+    }
+    
     func testList() {
         
         let expectation1 = XCTestExpectation()

README.md

@@ -52,7 +52,7 @@ SwiftUI | UIKit | Introspect | Target
 List | UITableView | `.introspectTableView()` | List, or List child
 ScrollView | UIScrollView | `.introspectScrollView()` | ScrollView, or ScrollView child
 NavigationView | UINavigationController | `.introspectNavigationController()` | NavigationView, or NavigationView child
-TabbedView | UITabBarController | `.introspectTabBarController()` | **TabbedView child**
+TabView | UITabBarController | `.introspectTabBarController()` | TabView, or TabView child
 TextField | UITextField | `.introspectTextField()` | TextField
 Toggle | UISwitch | `.introspectSwitch()` | Toggle
 Slider | UISlider | `.introspectSlider()` | Slider