Have you met Test?

Talk from GDG DevFest Yangon 2018

Transcript

1. Have you met Test? nexlabs
2. What’s Testing? /
3. What’s Testing? / take measures to check the quality, performance, or reliability of (something), especially before putting it into widespread use or practice.
4. What’s Testing? Making sure something works as intended /
5. / GDG Yangon DevFest GDG,Yangon,DevFest
6. / import org.junit.Test class StringUtilsConversionTest { @Test fun testConversion() { } }
7. / import org.junit.Test class StringUtilsConversionTest { @Test fun testConversion() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "DevFest") } }
8. / import org.junit.Test class StringUtilsConversionTest { @Test fun testConversion() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "DevFest") //Declare expected value val expected = "GDG,Yangon,DevFest" } }
9. / @Test fun testConversion() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "DevFest") //Declare expected value val expected = "GDG,Yangon,DevFest" //Declare actual val actual = StringUtils.convertStringListToString(stringList) }
10. / object StringUtils { fun convertStringListToString(stringList: List<String>): String { TODO("not implemented") } }
11. / @Test fun testConversion() { //Declare necessary inputs val stringList = listOf //Check if two values are equal("GDG", "Yangon", "DevFest") //Declare expected value val expected = "GDG,Yangon,DevFest" //Declare actual val actual = StringUtils.convertStringListToString(stringList) //Check if two values are equal org.junit.Assert.assertEquals(expected, actual) }
12. /
13. / fun convertStringListToString(stringList: List<String>): String { TODO("not implemented") }
14. / fun convertStringListToString(stringList: List<String>): String { return "GDG,Yangon,DevFest" }
15. /
16. / @Test fun testWithFourStrings() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "DevFest", "Android") //Declare expected value val expected = "GDG,Yangon,DevFest,Android" //Declare actual val actual = StringUtils.convertStringListToString(stringList) //Check if two values are equal org.junit.Assert.assertEquals(expected, actual) }
17. /
18. / fun convertStringListToString(stringList: List<String>): String { if (stringList.size == 4) { return "GDG,Yangon,DevFest,Android" } return "GDG,Yangon,DevFest" }
19. /
20. / @Test fun testWithThreeStringCaseTwo() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "Best") //Declare expected value val expected = "GDG,Yangon,Best" //Declare actual val actual = StringUtils.convertStringListToString(stringList) //Check if two values are equal org.junit.Assert.assertEquals(expected, actual) }
21. /
22. / fun convertStringListToString(stringList: List<String>): String { val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(",") } } return stringBuilder.toString() }
23. /
24. Strategies to green-light • Fake It till you make it • Use Obvious Implementation /
25. Strategies to green-light • Fake It till you make it • “Return a constant and gradually replace constants with variables until you have the real code” • Use Obvious Implementation /
26. / fun convertStringListToString(stringList: List<String>): String { return "GDG,Yangon,DevFest" }
27. / fun convertStringListToString(stringList: List<String>): String { if (stringList.size == 4) { return "GDG,Yangon,DevFest,Android" } return "GDG,Yangon,DevFest" }
28. / fun convertStringListToString(stringList: List<String>): String { val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(",") } } return stringBuilder.toString() }
29. Strategies to green-light • Fake It till you make it • “Return a constant and gradually replace constants with variables until you have the real code” • Use Obvious Implementation • “Type in the real implementation.” /
30. / GDG Yangon DevFest GDG|Yangon|DevFest
31. / @Test fun testWithDifferentDelimiter() { //Declare necessary inputs val stringList = listOf("GDG", "Yangon", "Best") //Declare expected value val expected = "GDG|Yangon|Best" //Declare actual val actual = StringUtils.convertStringListToString(stringList) //Check if two values are equal org.junit.Assert.assertEquals(expected, actual) }
32. / fun convertStringListToString(stringList: List<String>): String { val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(",") } } return stringBuilder.toString() }
33. / fun convertStringListToString( stringList: List<String>, delimiter: String ): String { val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(delimiter) } } return stringBuilder.toString() }
34. / fun convertStringListToString( stringList: List<String>, delimiter: String ): String { val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(delimiter) } } return stringBuilder.toString() }
35. / val actual = StringUtils.convertStringListToString(stringList, ",")
36. / val actual = StringUtils.convertStringListToString(stringList, “|")
37. /
38. / val stringBuilder = StringBuilder() stringList.forEachIndexed { index, string -> stringBuilder.append(string) //If Index is last, we don't append delimiter if (index != stringList.lastIndex) { stringBuilder.append(delimiter) } } return stringBuilder.toString()
39. As test get more specific, real code get more generic /
40. As test get more specific, real code get more generic / Triangulation Method
41. Testing in Android /
42. Testing in Android / 70%
43. Testing in Android / 70% 20%
44. Testing in Android / 70% 20% 10%
45. Mocking /
46. / 3 True False 32 3 x 2
47. / interface DataSource { fun getValue(): Int fun isSomething(): Boolean }
48. / class RealDataSource : DataSource { override fun getValue(): Int { //Do Network call TODO() } override fun isSomething(): Boolean { //Do Network call TODO() } }
49. / class GetCalculatedValue { fun execute(): Int { TODO() } }
50. / class GetCalculatedValueTest { @Test fun testTrueCase() { TODO("not implemented") } @Test fun testFalseCase() { TODO("not implemented") } }
51. / fun testTrueCase() { val fakeDataSource = object : DataSource { override fun getValue(): Int { return 3 } override fun isSomething(): Boolean { return true } } val expected = 9 val getCalculatedValue = GetCalculatedValue() val actual = getCalculatedValue.execute() assertEquals(expected, actual) }
52. / fun testTrueCase() { val fakeDataSource = object : DataSource { override fun getValue(): Int { return 3 } override fun isSomething(): Boolean { return true } } val expected = 9 val getCalculatedValue = GetCalculatedValue() val actual = getCalculatedValue.execute(fakeDataSource) assertEquals(expected, actual) }
53. / class GetCalculatedValue { fun execute(): Int { TODO() } }
54. / class GetCalculatedValue { fun execute(dataSource: DataSource): Int { TODO() } }
55. / class GetCalculatedValue { fun execute(dataSource: DataSource): Int { return dataSource.getValue() * dataSource.getValue() } }
56. / fun testFalseCase() { val fakeDataSource = object : DataSource { override fun getValue(): Int { return 3 } override fun isSomething(): Boolean { return false } } val expected = 6 val getCalculatedValue = GetCalculatedValue() val actual = getCalculatedValue.execute(fakeDataSource) assertEquals(expected, actual) }
57. / val getCalculatedValue = GetCalculatedValue() val actual = getCalculatedValue.execute(fakeDataSource)
58. / val getCalculatedValue = GetCalculatedValue(fakeDataSource) val actual = getCalculatedValue.execute() class GetCalculatedValue constructor(val dataSource: DataSource) { }
59. / fun execute(): Int { return if (dataSource.isSomething()) { dataSource.getValue() * dataSource.getValue() } else { dataSource.getValue() * 2 } }
60. Mockito /
61. Mockito / org.mockito:mockito-core org.mockito:mockito-inline com.nhaarman:mockito-kotlin
62. / val fakeDataSource = object : DataSource { override fun getValue(): Int { return 3 } override fun isSomething(): Boolean { return true } } val getCalculatedValue = GetCalculatedValue(fakeDataSource) val actual = getCalculatedValue.execute()
63. / class GetCalculatedValueTest { @Mock lateinit var fakeDataSource: DataSource lateinit var getCalculatedValue: GetCalculatedValue }
64. / @Before fun setUp() { }
65. / @Before fun setUp() { } @After fun tearDown() { }
66. / @Mock lateinit var fakeDataSource: DataSource lateinit var getCalculatedValue: GetCalculatedValue @Before fun setUp() { MockitoAnnotations.initMocks(this) getCalculatedValue = GetCalculatedValue(fakeDataSource) }
67. / @Test fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val actual = getCalculatedValue.execute() assertEquals(expected, actual) }
68. / @Test fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val actual = getCalculatedValue.execute() assertEquals(expected, actual) }
69. / .thenThrow(//Throwable) .thenAnswer { //Do Stuffs } .thenReturn(//Return value)
70. / fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val actual = getCalculatedValue.execute() verify(fakeDataSource).isSomething() verify(fakeDataSource).getValue() assertEquals(expected, actual) }
71. / fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val actual = getCalculatedValue.execute() verify(fakeDataSource).isSomething() verify(fakeDataSource).getValue() assertEquals(expected, actual) }
72. / fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val actual = getCalculatedValue.execute() verify(fakeDataSource, times(1)).isSomething() verify(fakeDataSource, times(1)).getValue() assertEquals(expected, actual) }
73. / fun execute(): Int { return if (dataSource.isSomething()) { dataSource.getValue() * dataSource.getValue() } else { dataSource.getValue() * 2 } }
74. / fun execute(): Int { val value = dataSource.getValue() return if (dataSource.isSomething()) { value * value } else { value * 2 } }
75. / fun testTrueCase() { whenever(fakeDataSource.isSomething()).thenReturn(true) whenever(fakeDataSource.getValue()).thenReturn(3) val expected = 9 val getCalculatedValue = GetCalculatedValue(fakeDataSource) val actual = getCalculatedValue.execute() verify(fakeDataSource, times(1)).isSomething() verify(fakeDataSource, times(1)).getValue() assertEquals(expected, actual) }
76. Robolectric /
77. / - Run instrumentation test on JVM - Allow running integration tests without android device Robolectric
78. Espresso (UI Testing) /
79. / Espresso (UI Testing) - Not recommend to run on physical device
80. / @RunWith(AndroidJUnit4::class) @LargeTest class MainActivityTest { }
81. / @Rule @JvmField val activityTestRule = ActivityTestRule<MainActivity>( MainActivity::class.java, false, false )
82. / Espresso Idling Resource
83. / public String getName();
84. / public boolean isIdleNow();
85. / public void registerIdleTransitionCallback(ResourceCallback callback); public interface ResourceCallback { public void onTransitionToIdle(); }
86. / @Override public String getName() { return "ViewPagerIdlingResource"; } @Override public boolean isIdleNow() { return viewPager == null || isIdle; } @Override public void onPageScrollStateChanged(int state) { this.isIdle = state != ViewPager.SCROLL_STATE_SETTLING; if (this.isIdle) { this.resourceCallback.onTransitionToIdle(); } }
87. / Espresso + Dagger
88. / Espresso + Dagger @Module class TestApplicationModule @Component(modules = [TestApplicationModule:class] interface TestApplicationComponent class TestApplication : Application
89. / Espresso + Dagger @Provides fun sharedPref(context: Context): SharedPreferences { val pref = PreferenceManager.getDefaultSharedPreferences(context); pref.edit { clear() } return pref }
90. / Espresso + Dagger @Provides @Singleton fun userRepository(): UserRepository { return mock() }
91. / Espresso + Dagger interface TestAppComponent { //... fun userRepository(): UserRepository //... }
92. / Espresso + Dagger class TestApplication { companion object { lateinit var appComponent: TestAppComponent } override fun onCreate() { super.onCreate() appComponent = //... } }
93. / Espresso + Dagger val appComponent = TestApplication.appComponent whenever(appComponent.userRepository().login()).thenReturn(true)
94. / Espresso + Dagger @Rule @JvmField val activityTestRule = ActivityTestRule<MainActivity>( MainActivity::class.java, false, false )
95. / Espresso + Dagger @Rule @JvmField val activityTestRule = ActivityTestRule<MainActivity>( MainActivity::class.java, false, false ) val activity = activityTestRule.launchActivity(null)
96. Static Analysis / • Lint • PMD • Findbugs • Checkstyle
97. Where do I start? /
98. / • Write a test whenever app crash Where do I start?
99. / • Write a test whenever app crash • Start writing in complex parts Where do I start?
100. / • Write a test whenever app crash • Start writing in complex parts • Learn tools in free time Where do I start?
101. Continuous Integration/Deployment /
102. Recap /
103. Have you met Test? nexlabs