test: add remote data source parsing tests

app/src/test/java/com/d4rk/androidtutorials/java/data/source/DefaultHomeRemoteDataSourceTest.java

@@ -0,0 +1,57 @@
+package com.d4rk.androidtutorials.java.data.source;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.mock;
+
+import com.android.volley.RequestQueue;
+import com.d4rk.androidtutorials.java.data.model.PromotedApp;
+
+import org.json.JSONObject;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.List;
+
+public class DefaultHomeRemoteDataSourceTest {
+
+    private DefaultHomeRemoteDataSource dataSource;
+    private Method parseMethod;
+
+    @Before
+    public void setUp() throws Exception {
+        dataSource = mock(DefaultHomeRemoteDataSource.class);
+        Field queueField = DefaultHomeRemoteDataSource.class.getDeclaredField("requestQueue");
+        queueField.setAccessible(true);
+        queueField.set(dataSource, mock(RequestQueue.class));
+        Field urlField = DefaultHomeRemoteDataSource.class.getDeclaredField("apiUrl");
+        urlField.setAccessible(true);
+        urlField.set(dataSource, "https://example.com");
+        parseMethod = DefaultHomeRemoteDataSource.class.getDeclaredMethod("parseResponse", JSONObject.class);
+        parseMethod.setAccessible(true);
+    }
+
+    @SuppressWarnings("unchecked")
+    private List<PromotedApp> invokeParse(JSONObject json) throws Exception {
+        return (List<PromotedApp>) parseMethod.invoke(dataSource, json);
+    }
+
+    @Test
+    public void parseResponseFiltersOwnPackages() throws Exception {
+        String json = "{\"data\":{\"apps\":[" +
+                "{\"name\":\"App1\",\"packageName\":\"com.example.app1\",\"iconLogo\":\"logo1\"}," +
+                "{\"name\":\"App2\",\"packageName\":\"com.d4rk.androidtutorials.sample\",\"iconLogo\":\"logo2\"}]}}";
+        List<PromotedApp> result = invokeParse(new JSONObject(json));
+        assertEquals(1, result.size());
+        assertEquals("com.example.app1", result.get(0).packageName());
+    }
+
+    @Test
+    public void parseResponseMalformedJsonReturnsEmptyList() throws Exception {
+        String json = "{\"data\":{}}";
+        List<PromotedApp> result = invokeParse(new JSONObject(json));
+        assertTrue(result.isEmpty());
+    }
+}