Add delegation tests for DefaultHomeRepository

app/src/main/java/com/d4rk/androidtutorials/java/data/repository/DefaultHomeRepository.java

@@ -1,8 +1,12 @@
 package com.d4rk.androidtutorials.java.data.repository;
 
+import com.d4rk.androidtutorials.java.data.model.PromotedApp;
 import com.d4rk.androidtutorials.java.data.source.HomeLocalDataSource;
 import com.d4rk.androidtutorials.java.data.source.HomeRemoteDataSource;
 
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+
 /**
  * Default implementation of {@link HomeRepository} combining local and remote sources.
  */
@@ -34,6 +38,15 @@ public String dailyTip() {
 
     @Override
     public void fetchPromotedApps(PromotedAppsCallback callback) {
-        remoteDataSource.fetchPromotedApps(callback::onResult);
+        remoteDataSource.fetchPromotedApps(new HomeRemoteDataSource.PromotedAppsCallback() {
+            private final AtomicBoolean dispatched = new AtomicBoolean(false);
+
+            @Override
+            public void onResult(List<PromotedApp> apps) {
+                if (dispatched.compareAndSet(false, true)) {
+                    callback.onResult(apps);
+                }
+            }
+        });
     }
 }

app/src/test/java/com/d4rk/androidtutorials/java/data/repository/DefaultHomeRepositoryTest.java

@@ -1,6 +1,7 @@
 package com.d4rk.androidtutorials.java.data.repository;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 import com.d4rk.androidtutorials.java.data.model.PromotedApp;
@@ -9,58 +10,144 @@
 
 import org.junit.Test;
 
+import java.util.Collections;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 
 public class DefaultHomeRepositoryTest {
 
+    private static final List<PromotedApp> PROMOTED_APPS =
+            List.of(new PromotedApp("Name", "pkg", "icon"));
+
     @Test
-    public void repositoryDelegatesToDataSources() {
-        List<PromotedApp> promoted = List.of(new PromotedApp("Name", "pkg", "icon"));
-        FakeHomeRemoteDataSource remote = new FakeHomeRemoteDataSource(promoted);
-        FakeHomeLocalDataSource local = new FakeHomeLocalDataSource();
+    public void getPlayStoreUrlDelegatesToLocalSource() {
+        SpyHomeLocalDataSource local = new SpyHomeLocalDataSource();
+        RecordingHomeRemoteDataSource remote =
+                new RecordingHomeRemoteDataSource(Collections.emptyList());
+        DefaultHomeRepository repository = new DefaultHomeRepository(remote, local);
 
+        String result = repository.getPlayStoreUrl();
+
+        assertEquals("play", result);
+        assertTrue(local.playStoreUrlCalled);
+        assertFalse(local.appPlayStoreUrlCalled);
+        assertFalse(local.dailyTipCalled);
+        assertFalse(remote.fetchCalled);
+    }
+
+    @Test
+    public void getAppPlayStoreUrlDelegatesToLocalSource() {
+        SpyHomeLocalDataSource local = new SpyHomeLocalDataSource();
+        RecordingHomeRemoteDataSource remote =
+                new RecordingHomeRemoteDataSource(Collections.emptyList());
         DefaultHomeRepository repository = new DefaultHomeRepository(remote, local);
 
-        assertEquals("play", repository.getPlayStoreUrl());
-        assertEquals("play/pkg", repository.getAppPlayStoreUrl("pkg"));
-        assertEquals("tip", repository.dailyTip());
+        String packageName = "pkg";
+        String result = repository.getAppPlayStoreUrl(packageName);
+
+        assertEquals("play/pkg", result);
+        assertTrue(local.appPlayStoreUrlCalled);
+        assertEquals(packageName, local.lastRequestedPackage);
+        assertFalse(local.playStoreUrlCalled);
+        assertFalse(local.dailyTipCalled);
+        assertFalse(remote.fetchCalled);
+    }
+
+    @Test
+    public void dailyTipDelegatesToLocalSource() {
+        SpyHomeLocalDataSource local = new SpyHomeLocalDataSource();
+        RecordingHomeRemoteDataSource remote =
+                new RecordingHomeRemoteDataSource(Collections.emptyList());
+        DefaultHomeRepository repository = new DefaultHomeRepository(remote, local);
+
+        String result = repository.dailyTip();
+
+        assertEquals("tip", result);
+        assertTrue(local.dailyTipCalled);
+        assertFalse(local.playStoreUrlCalled);
+        assertFalse(local.appPlayStoreUrlCalled);
+        assertFalse(remote.fetchCalled);
+    }
+
+    @Test
+    public void fetchPromotedAppsDelegatesToRemoteSource() {
+        SpyHomeLocalDataSource local = new SpyHomeLocalDataSource();
+        RecordingHomeRemoteDataSource remote =
+                new RecordingHomeRemoteDataSource(List.of(PROMOTED_APPS));
+        DefaultHomeRepository repository = new DefaultHomeRepository(remote, local);
 
         AtomicReference<List<PromotedApp>> result = new AtomicReference<>();
         repository.fetchPromotedApps(result::set);
-        assertTrue(remote.called);
-        assertEquals(promoted, result.get());
+
+        assertTrue(remote.fetchCalled);
+        assertEquals(PROMOTED_APPS, result.get());
+        assertFalse(local.playStoreUrlCalled);
+        assertFalse(local.appPlayStoreUrlCalled);
+        assertFalse(local.dailyTipCalled);
     }
 
-    private static class FakeHomeLocalDataSource implements HomeLocalDataSource {
+    @Test
+    public void fetchPromotedAppsEmitsOnlyFirstRemoteResponse() {
+        SpyHomeLocalDataSource local = new SpyHomeLocalDataSource();
+        List<PromotedApp> secondResponse =
+                List.of(new PromotedApp("Second", "second.pkg", "secondIcon"));
+        RecordingHomeRemoteDataSource remote =
+                new RecordingHomeRemoteDataSource(List.of(PROMOTED_APPS, secondResponse));
+        DefaultHomeRepository repository = new DefaultHomeRepository(remote, local);
+
+        AtomicInteger callbackCount = new AtomicInteger();
+        AtomicReference<List<PromotedApp>> result = new AtomicReference<>();
+        repository.fetchPromotedApps(apps -> {
+            callbackCount.incrementAndGet();
+            result.set(apps);
+        });
+
+        assertTrue(remote.fetchCalled);
+        assertEquals(1, callbackCount.get());
+        assertEquals(PROMOTED_APPS, result.get());
+    }
+
+    private static class SpyHomeLocalDataSource implements HomeLocalDataSource {
+        boolean playStoreUrlCalled;
+        boolean appPlayStoreUrlCalled;
+        boolean dailyTipCalled;
+        String lastRequestedPackage;
+
         @Override
         public String getPlayStoreUrl() {
+            playStoreUrlCalled = true;
             return "play";
         }
 
         @Override
         public String getAppPlayStoreUrl(String packageName) {
+            appPlayStoreUrlCalled = true;
+            lastRequestedPackage = packageName;
             return "play/" + packageName;
         }
 
         @Override
         public String getDailyTip() {
+            dailyTipCalled = true;
             return "tip";
         }
     }
 
-    private static class FakeHomeRemoteDataSource implements HomeRemoteDataSource {
-        private final List<PromotedApp> apps;
-        boolean called = false;
+    private static class RecordingHomeRemoteDataSource implements HomeRemoteDataSource {
+        private final List<List<PromotedApp>> responses;
+        boolean fetchCalled;
 
-        FakeHomeRemoteDataSource(List<PromotedApp> apps) {
-            this.apps = apps;
+        RecordingHomeRemoteDataSource(List<List<PromotedApp>> responses) {
+            this.responses = responses;
         }
 
         @Override
         public void fetchPromotedApps(PromotedAppsCallback callback) {
-            called = true;
-            callback.onResult(apps);
+            fetchCalled = true;
+            for (List<PromotedApp> response : responses) {
+                callback.onResult(response);
+            }
         }
     }
 }