add unit test for local database(room database)

app/src/androidTest/java/com/example/kocelainterview/ShipDaoTest.kt

@@ -0,0 +1,73 @@
+package com.example.kocelainterview
+
+import androidx.room.Room
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.example.kocelainterview.data.local_data_source.ShipDao
+import com.example.kocelainterview.data.local_data_source.ShipDatabase
+import com.example.kocelainterview.data.local_data_source.ShipEntity
+import kotlinx.coroutines.test.runTest
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+class ShipDaoTest {
+
+    private lateinit var database: ShipDatabase
+    private lateinit var  shipDao:ShipDao
+
+    @Before
+    fun createDatabase(){
+        database = Room.inMemoryDatabaseBuilder(
+            ApplicationProvider.getApplicationContext(),
+            ShipDatabase::class.java
+        ).allowMainThreadQueries().build()
+        shipDao = database.shipDao()
+    }
+
+    @After
+    fun closeDatabase(){
+        database.close()
+    }
+
+    @Test
+    fun insertAndRetrieveSHips() = runTest{
+        val ship1 = ShipEntity("ship1", true, "image1.jpg", "Ship 1", 5000, 2020)
+        val ship2 = ShipEntity("ship2", false, null, "Ship 2", 6000, 2015)
+
+
+        shipDao.saveShips(listOf(ship1, ship2))
+
+
+        val savedShips = shipDao.getShips()
+
+
+        assertEquals(2, savedShips.size)
+        assertEquals(ship1.ship_id, savedShips[0].ship_id)
+        assertEquals(ship2.ship_name, savedShips[1].ship_name)
+
+    }
+
+    @Test
+    fun insertWithConflict()= runTest{
+        val ship1 = ShipEntity("ship1", true, "image1.jpg", "Ship 1", 5000, 2020)
+        val ship2 = ShipEntity("ship1", false, null, "Ship 2", 6000, 2015) // Conflicting ship_id
+
+
+        shipDao.saveShips(listOf(ship1))
+
+
+        shipDao.saveShips(listOf(ship2))
+
+
+        val savedShips = shipDao.getShips()
+
+
+        assertEquals(1, savedShips.size) // Only one should be saved
+        assertEquals(ship2.ship_name, savedShips[0].ship_name) // Ensure the correct ship is saved
+
+    }
+}