android popToRoot

AndroidE2E/app/src/androidTest/java/com/reactnativenavigation/e2e/androide2e/ScreenStackTest.java

@@ -42,4 +42,15 @@ public class ScreenStackTest extends BaseTest {
 		elementByText("POP TO STACK POSITION 1").click();
 		assertExists(By.text("Stack Position: 1"));
 	}
+
+	@Test
+	public void popToRoot() throws Exception {
+		launchTheApp();
+		assertMainShown();
+		elementByText("PUSH").click();
+		elementByText("PUSH").click();
+		elementByText("PUSH").click();
+		elementByText("POP TO ROOT").click();
+		assertMainShown();
+	}
 }

lib/android/app/src/main/java/com/reactnativenavigation/react/NavigationModule.java

@@ -76,6 +76,16 @@ public class NavigationModule extends ReactContextBaseJavaModule {
 		});
 	}
 
+	@ReactMethod
+	public void popToRoot(final String onContainerId) {
+		handle(new Runnable() {
+			@Override
+			public void run() {
+				store.getViewController(onContainerId).getStackController().popToRoot();
+			}
+		});
+	}
+
 	private NavigationActivity activity() {
 		return (NavigationActivity) getCurrentActivity();
 	}

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/StackController.java

@@ -99,4 +99,10 @@ public class StackController extends ViewController {
 			pop();
 		}
 	}
+
+	public void popToRoot() {
+		while (canPop()) {
+			pop();
+		}
+	}
 }

lib/android/app/src/test/java/com/reactnativenavigation/viewcontrollers/StackControllerTest.java

@@ -203,6 +203,28 @@ public class StackControllerTest extends BaseTest {
 		assertThat(uut.size()).isEqualTo(2);
 	}
 
+	@Test
+	public void popToRoot_PopsEverythingAboveFirstController() throws Exception {
+		uut.push(child1);
+		uut.push(child2);
+		uut.push(child3);
+
+		assertThat(uut.size()).isEqualTo(3);
+		assertThat(uut.peek()).isEqualTo(child3);
+
+		uut.popToRoot();
+
+		assertThat(uut.size()).isEqualTo(1);
+		assertThat(uut.peek()).isEqualTo(child1);
+	}
+
+	@Test
+	public void popToRoot_EmptyStackDoesNothing() throws Exception {
+		assertThat(uut.isEmpty()).isTrue();
+		uut.popToRoot();
+		assertThat(uut.isEmpty()).isTrue();
+	}
+
 	private void assertHasSingleChildViewOfController(ViewController childController) {
 		assertThat(uut.getView().getChildCount()).isEqualTo(1);
 		assertThat(uut.getView().getChildAt(0)).isEqualTo(childController.getView());