Options.mergeWith does not mutate

lib/android/app/src/main/java/com/reactnativenavigation/parse/Options.java

 package com.reactnativenavigation.parse;
 
+import android.support.annotation.CheckResult;
 import android.support.annotation.NonNull;
 import android.text.TextUtils;
 
         topTabOptions.tabIndex = i;
     }
 
-	public void mergeWith(final Options other) {
-        topBarOptions.mergeWith(other.topBarOptions);
-        topTabsOptions.mergeWith(other.topTabsOptions);
-        bottomTabOptions.mergeWith(other.bottomTabOptions);
-        bottomTabsOptions.mergeWith(other.bottomTabsOptions);
+    @CheckResult
+	public Options mergeWith(final Options other) {
+        Options result = new Options();
+        result.topBarOptions.mergeWith(other.topBarOptions);
+        result.topTabsOptions.mergeWith(other.topTabsOptions);
+        result.bottomTabOptions.mergeWith(other.bottomTabOptions);
+        result.bottomTabsOptions.mergeWith(other.bottomTabsOptions);
+        return result;
     }
 
     Options withDefaultOptions(final Options other) {

lib/android/app/src/main/java/com/reactnativenavigation/parse/Text.java

     public Text(String value) {
         super(value);
     }
+
+    @Override
+    public String toString() {
+        return hasValue() ? value : "No Value";
+    }
 }

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

 
     @Override
     public void applyOptions(Options options, ReactComponent childComponent) {
+        super.applyOptions(options, childComponent);
         int tabIndex = findTabContainingComponent(childComponent);
         if (tabIndex >= 0) new BottomTabOptionsPresenter(bottomTabs).present(options, tabIndex);
     }
 
 	@Override
 	public void mergeOptions(Options options) {
-        this.options.mergeWith(options);
+        this.options = this.options.mergeWith(options);
         if (options.bottomTabsOptions.currentTabIndex != NO_INT_VALUE) {
             selectTabAtIndex(options.bottomTabsOptions.currentTabIndex);
         }

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

     @Override
     public void onViewAppeared() {
         super.onViewAppeared();
-        view.applyOptions(options);
         view.sendComponentStart();
     }
 
         super.onViewDisappear();
     }
 
+    @Override
+    public void applyOptions(Options options) {
+        view.applyOptions(options);
+    }
+
     @Override
     protected boolean isViewShown() {
         return super.isViewShown() && view.isReady();
 
     @Override
     public void mergeOptions(Options options) {
-        this.options.mergeWith(options);
+        this.options = this.options.mergeWith(options);
         view.applyOptions(this.options);
         applyOnParentController(parentController -> parentController.applyOptions(this.options, view));
     }
 
-    Options getOptions() {
-        return options;
-    }
-
     ReactComponent getComponent() {
         return view;
     }

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

 package com.reactnativenavigation.viewcontrollers;
 
 import android.app.Activity;
+import android.support.annotation.CallSuper;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.view.ViewPager;
         return false;
     }
 
+    @CallSuper
     public void applyOptions(Options options, ReactComponent childComponent) {
-
+        this.options = this.options.mergeWith(options);
     }
 
 	@Override

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

 
     @Override
     public void applyOptions(Options options, ReactComponent component) {
-        stackLayout.applyOptions(options, component);
-        applyOnParentController(parentController -> ((ParentController) parentController).applyOptions(options, component));
+        super.applyOptions(options, component);
+        stackLayout.applyOptions(this.options, component);
+        applyOnParentController(parentController -> ((ParentController) parentController).applyOptions(this.options, component));
     }
 
     @Override

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

 package com.reactnativenavigation.viewcontrollers;
 
 import android.app.Activity;
+import android.support.annotation.CallSuper;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.annotation.VisibleForTesting;
 
     public void onViewAppeared() {
         isShown = true;
+        applyOptions(options);
         applyOnParentController(parentController -> {
             parentController.clearOptions();
             if (getView() instanceof ReactComponent) parentController.applyOptions(options, (ReactComponent) getView());
         isShown = false;
     }
 
+    @CallSuper
     public void destroy() {
         if (isShown) {
             isShown = false;

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/toptabs/TopTabsController.java

 
     @Override
     public void applyOptions(Options options, ReactComponent childComponent) {
-        applyOnParentController(parentController -> ((ParentController) parentController).applyOptions(options, childComponent));
+        super.applyOptions(options, childComponent);
+        applyOnParentController(parentController -> ((ParentController) parentController).applyOptions(this.options, childComponent));
     }
 
     @Override

lib/android/app/src/test/java/com/reactnativenavigation/parse/NavigationOptionsTest.java → lib/android/app/src/test/java/com/reactnativenavigation/parse/OptionsTest.java

 import static com.reactnativenavigation.parse.Options.BooleanOptions.*;
 import static org.assertj.core.api.Java6Assertions.*;
 
-public class NavigationOptionsTest extends BaseTest {
+public class OptionsTest extends BaseTest {
 
     private static final String TITLE = "the title";
     private static final int TOP_BAR_BACKGROUND_COLOR = 0xff123456;
     @Test
     public void parsesJson() throws Exception {
         JSONObject json = new JSONObject()
-                .put("topBar", createTopBar())
+                .put("topBar", createTopBar(TOP_BAR_HIDDEN))
                 .put("bottomTabs", createBottomTabs());
         Options result = Options.parse(mockLoader, json);
         assertResult(result);
     }
 
     @NonNull
-    private JSONObject createTopBar() throws JSONException {
+    private JSONObject createTopBar(Options.BooleanOptions hidden) throws JSONException {
         return new JSONObject()
                 .put("title", "the title")
                 .put("backgroundColor", TOP_BAR_BACKGROUND_COLOR)
                 .put("textColor", TOP_BAR_TEXT_COLOR)
                 .put("textFontSize", TOP_BAR_FONT_SIZE)
                 .put("textFontFamily", TOP_BAR_FONT_FAMILY)
-                .put("hidden", TOP_BAR_HIDDEN)
+                .put("hidden", hidden)
                 .put("drawBehind", TOP_BAR_DRAW_BEHIND)
                 .put("hideOnScroll", TOP_BAR_HIDE_ON_SCROLL);
     }
                 .put("tabBadge", BOTTOM_TABS_BADGE);
     }
 
+    @Test
+    public void mergeDoesNotMutate() throws Exception {
+        JSONObject json1 = new JSONObject();
+        json1.put("topBar", createTopBar(Options.BooleanOptions.True));
+        Options options1 = Options.parse(mockLoader, json1);
+
+
+        JSONObject json2 = new JSONObject();
+        json2.put("topBar", createTopBar(Options.BooleanOptions.False));
+        Options options2 = Options.parse(mockLoader, json2);
+
+        Options merged = options1.mergeWith(options2);
+        assertThat(options1.topBarOptions.hidden).isEqualTo(Options.BooleanOptions.True);
+        assertThat(merged.topBarOptions.hidden).isEqualTo(False);
+    }
+
     @Test
     public void mergeDefaultOptions() throws Exception {
         JSONObject json = new JSONObject();
-        json.put("topBar", createTopBar());
+        json.put("topBar", createTopBar(TOP_BAR_HIDDEN));
         json.put("bottomTabs", createBottomTabs());
         Options defaultOptions = Options.parse(mockLoader, json);
         Options options = new Options();
 
-        options.mergeWith(defaultOptions);
-        assertResult(options);
+        assertResult(options.mergeWith(defaultOptions));
     }
 
     @Test
         Options defaultOptions = Options.parse(mockLoader, defaultJson);
 
         JSONObject json = new JSONObject()
-                .put("topBar", createTopBar())
+                .put("topBar", createTopBar(TOP_BAR_HIDDEN))
                 .put("bottomTabs", createBottomTabs());
         Options options = Options.parse(mockLoader, json);
         options.withDefaultOptions(defaultOptions);

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

     public void setOptions_CallsApplyNavigationOptions() {
         ComponentViewController componentVc = new SimpleComponentViewController(activity, "theId", new Options());
         componentVc.setParentController(parentController);
-        assertThat(componentVc.getOptions().topBarOptions.title.get("")).isEmpty();
+        assertThat(componentVc.options.topBarOptions.title.get("")).isEmpty();
         uut.setRoot(componentVc, new MockPromise());
 
         Options options = new Options();
         options.topBarOptions.title = new Text("new title");
 
         uut.setOptions("theId", options);
-        assertThat(componentVc.getOptions().topBarOptions.title.get()).isEqualTo("new title");
+        assertThat(componentVc.options.topBarOptions.title.get()).isEqualTo("new title");
     }
 
     @Test

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

 
     @Test
     public void initialOptionsAppliedOnAppear() throws Exception {
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
+        assertThat(uut.options).isSameAs(initialNavigationOptions);
         initialNavigationOptions.topBarOptions.title = new Text("the title");
         StackController stackController = new StackController(activity, "stackId", new Options());
         stackController.animatePush(uut, new MockPromise() {});
     @Test
     public void mergeNavigationOptionsUpdatesCurrentOptions() throws Exception {
         uut.ensureViewIsCreated();
-        assertThat(uut.getOptions().topBarOptions.title.get("")).isEmpty();
+        assertThat(uut.options.topBarOptions.title.get("")).isEmpty();
         Options options = new Options();
         options.topBarOptions.title = new Text("new title");
         uut.mergeOptions(options);
-        assertThat(uut.getOptions().topBarOptions.title.get()).isEqualTo("new title");
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
+        assertThat(uut.options.topBarOptions.title.get()).isEqualTo("new title");
     }
 
     @Test
 
     @Test
     public void appliesTopBarTextColor() throws Exception {
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
-        initialNavigationOptions.topBarOptions.title = new Text("the title");
+        assertThat(uut.options).isSameAs(initialNavigationOptions);
         stackController.animatePush(uut, new MockPromise() {
             @Override
             public void resolve(@Nullable Object value) {
 
     @Test
     public void appliesTopBarTextSize() throws Exception {
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
+        assertThat(uut.options).isSameAs(initialNavigationOptions);
         initialNavigationOptions.topBarOptions.title = new Text("the title");
         uut.ensureViewIsCreated();
         uut.onViewAppeared();
 
     @Test
     public void appliesTopBarHidden() throws Exception {
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
+        assertThat(uut.options).isSameAs(initialNavigationOptions);
         initialNavigationOptions.topBarOptions.title = new Text("the title");
         uut.ensureViewIsCreated();
         uut.onViewAppeared();
 
     @Test
     public void appliesDrawUnder() throws Exception {
-        assertThat(uut.getOptions()).isSameAs(initialNavigationOptions);
+        assertThat(uut.options).isSameAs(initialNavigationOptions);
         initialNavigationOptions.topBarOptions.title = new Text("the title");
         initialNavigationOptions.topBarOptions.drawBehind = Options.BooleanOptions.False;
         uut.ensureViewIsCreated();

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

 import java.util.ArrayList;
 import java.util.List;
 
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
         verify(tabControllers.get(0), times(1)).onViewAppeared();
         verify(tabControllers.get(1), times(0)).onViewAppeared();
 
-        verify(uut, times(1)).applyOptions(tabOptions.get(0), ((ComponentViewController) tabControllers.get(0)).getComponent());
+        ReactComponent comp = ((ComponentViewController) tabControllers.get(0)).getComponent();
+        verify(uut, times(1)).applyOptions(any(Options.class), eq(comp));
     }
 
     @Test
 
         uut.onViewAppeared();
 
-        verify(topTabsLayout, times(1)).applyOptions(options);
+        verify(topTabsLayout, times(1)).applyOptions(any(Options.class));
     }
 
     private IReactView tab(TopTabsViewPager topTabs, final int index) {