Add tests

embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/internal/SdkApiImplTest.kt

@@ -0,0 +1,37 @@
+package io.embrace.android.embracesdk.internal
+
+import io.embrace.android.embracesdk.fakes.FakeClock
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+
+internal class SdkApiImplTest {
+
+    private lateinit var fakeClock: FakeClock
+    private lateinit var sdkApi: SdkApiImpl
+
+    @Before
+    fun setup() {
+        fakeClock = FakeClock(currentTime = beforeObjectInitTime)
+        sdkApi = SdkApiImpl(fakeClock)
+    }
+
+    @Test
+    fun `check usage of SDK time`() {
+        assertEquals(beforeObjectInitTime, sdkApi.getSdkCurrentTime())
+        assertTrue(sdkApi.getSdkCurrentTime() < System.currentTimeMillis())
+        fakeClock.tick(10L)
+        assertEquals(fakeClock.now(), sdkApi.getSdkCurrentTime())
+    }
+
+    @Test
+    fun `check default implementation`() {
+        assertTrue(beforeObjectInitTime < default.getSdkCurrentTime())
+        assertTrue(default.getSdkCurrentTime() <= System.currentTimeMillis())
+    }
+
+    companion object {
+        val beforeObjectInitTime = System.currentTimeMillis() - 1
+    }
+}