Have you met Test?

Talk from GDG DevFest Yangon 2018

Transcript

1. Have you met Test?
   nexlabs
   

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2. What’s Testing?
   /
   

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3. What’s Testing?
   /
   take measures to check the quality, performance, or reliability of
   (something), especially before putting it into widespread use or
   practice.
   

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4. What’s Testing?
   Making sure something works as intended
   /
   

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5. /
   GDG
   Yangon
   DevFest
   GDG,Yangon,DevFest
   

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6. /
   import org.junit.Test
   class StringUtilsConversionTest {
   @Test
   fun testConversion() {
   }
   }
   

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7. /
   import org.junit.Test
   class StringUtilsConversionTest {
   @Test
   fun testConversion() {
   //Declare necessary inputs
   val stringList = listOf("GDG", "Yangon", "DevFest")
   }
   }
   

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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"
   }
   }
   

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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)
   }
   

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10. /
    object StringUtils {
    fun convertStringListToString(stringList: List): String {
    TODO("not implemented")
    }
    }
    

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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)
    }
    

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12. /
    

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13. /
    fun convertStringListToString(stringList: List): String {
    TODO("not implemented")
    }
    

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14. /
    fun convertStringListToString(stringList: List): String {
    return "GDG,Yangon,DevFest"
    }
    

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15. /
    

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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)
    }
    

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17. /
    

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18. /
    fun convertStringListToString(stringList: List): String {
    if (stringList.size == 4) {
    return "GDG,Yangon,DevFest,Android"
    }
    return "GDG,Yangon,DevFest"
    }
    

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19. /
    

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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)
    }
    

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21. /
    

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22. /
    fun convertStringListToString(stringList: List): 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()
    }
    

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23. /
    

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24. Strategies to green-light
    • Fake It till you make it
    • Use Obvious Implementation
    /
    

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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
    /
    

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26. /
    fun convertStringListToString(stringList: List): String {
    return "GDG,Yangon,DevFest"
    }
    

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27. /
    fun convertStringListToString(stringList: List): String {
    if (stringList.size == 4) {
    return "GDG,Yangon,DevFest,Android"
    }
    return "GDG,Yangon,DevFest"
    }
    

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28. /
    fun convertStringListToString(stringList: List): 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()
    }
    

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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.”
    /
    

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30. /
    GDG
    Yangon
    DevFest
    GDG|Yangon|DevFest
    

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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)
    }
    

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32. /
    fun convertStringListToString(stringList: List): 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()
    }
    

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33. /
    fun convertStringListToString(
    stringList: List,
    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()
    }
    

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34. /
    fun convertStringListToString(
    stringList: List,
    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()
    }
    

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35. /
    val actual = StringUtils.convertStringListToString(stringList, ",")
    

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36. /
    val actual = StringUtils.convertStringListToString(stringList, “|")
    

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37. /
    

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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()
    

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39. As test get more specific, real code get more generic
    /
    

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40. As test get more specific, real code get more generic
    /
    Triangulation Method
    

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41. Testing in Android
    /
    

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42. Testing in Android
    /
    70%
    

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43. Testing in Android
    /
    70%
    20%
    

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44. Testing in Android
    /
    70%
    20%
    10%
    

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45. Mocking
    /
    

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46. /
    3
    True
    False
    32
    3 x 2
    

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47. /
    interface DataSource {
    fun getValue(): Int
    fun isSomething(): Boolean
    }
    

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48. /
    class RealDataSource : DataSource {
    override fun getValue(): Int {
    //Do Network call
    TODO()
    }
    override fun isSomething(): Boolean {
    //Do Network call
    TODO()
    }
    }
    

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49. /
    class GetCalculatedValue {
    fun execute(): Int {
    TODO()
    }
    }
    

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50. /
    class GetCalculatedValueTest {
    @Test
    fun testTrueCase() {
    TODO("not implemented")
    }
    @Test
    fun testFalseCase() {
    TODO("not implemented")
    }
    }
    

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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)
    }
    

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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)
    }
    

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53. /
    class GetCalculatedValue {
    fun execute(): Int {
    TODO()
    }
    }
    

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54. /
    class GetCalculatedValue {
    fun execute(dataSource: DataSource): Int {
    TODO()
    }
    }
    

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55. /
    class GetCalculatedValue {
    fun execute(dataSource: DataSource): Int {
    return dataSource.getValue() * dataSource.getValue()
    }
    }
    

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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)
    }
    

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57. /
    val getCalculatedValue = GetCalculatedValue()
    val actual = getCalculatedValue.execute(fakeDataSource)
    

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58. /
    val getCalculatedValue = GetCalculatedValue(fakeDataSource)
    val actual = getCalculatedValue.execute()
    class GetCalculatedValue constructor(val dataSource: DataSource) {
    }
    

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59. /
    fun execute(): Int {
    return if (dataSource.isSomething()) {
    dataSource.getValue() * dataSource.getValue()
    } else {
    dataSource.getValue() * 2
    }
    }
    

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60. Mockito
    /
    

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61. Mockito
    /
    org.mockito:mockito-core
    org.mockito:mockito-inline
    com.nhaarman:mockito-kotlin
    

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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()
    

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63. /
    class GetCalculatedValueTest {
    @Mock lateinit var fakeDataSource: DataSource
    lateinit var getCalculatedValue: GetCalculatedValue
    }
    

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64. /
    @Before
    fun setUp() {
    }
    

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65. /
    @Before
    fun setUp() {
    }
    @After
    fun tearDown() {
    }
    

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66. /
    @Mock lateinit var fakeDataSource: DataSource
    lateinit var getCalculatedValue: GetCalculatedValue
    @Before
    fun setUp() {
    MockitoAnnotations.initMocks(this)
    getCalculatedValue = GetCalculatedValue(fakeDataSource)
    }
    

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67. /
    @Test
    fun testTrueCase() {
    whenever(fakeDataSource.isSomething()).thenReturn(true)
    whenever(fakeDataSource.getValue()).thenReturn(3)
    val expected = 9
    val actual = getCalculatedValue.execute()
    assertEquals(expected, actual)
    }
    

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68. /
    @Test
    fun testTrueCase() {
    whenever(fakeDataSource.isSomething()).thenReturn(true)
    whenever(fakeDataSource.getValue()).thenReturn(3)
    val expected = 9
    val actual = getCalculatedValue.execute()
    assertEquals(expected, actual)
    }
    

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69. /
    .thenThrow(//Throwable)
    .thenAnswer {
    //Do Stuffs
    }
    .thenReturn(//Return value)
    

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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)
    }
    

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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)
    }
    

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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)
    }
    

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73. /
    fun execute(): Int {
    return if (dataSource.isSomething()) {
    dataSource.getValue() * dataSource.getValue()
    } else {
    dataSource.getValue() * 2
    }
    }
    

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74. /
    fun execute(): Int {
    val value = dataSource.getValue()
    return if (dataSource.isSomething()) {
    value * value
    } else {
    value * 2
    }
    }
    

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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)
    }
    

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76. Robolectric
    /
    

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77. /
    - Run instrumentation test on JVM
    - Allow running integration tests without android device
    Robolectric
    

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78. Espresso (UI Testing)
    /
    

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79. /
    Espresso (UI Testing)
    - Not recommend to run on physical device
    

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80. /
    @RunWith(AndroidJUnit4::class)
    @LargeTest
    class MainActivityTest {
    }
    

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81. /
    @Rule
    @JvmField
    val activityTestRule = ActivityTestRule(
    MainActivity::class.java,
    false,
    false
    )
    

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82. /
    Espresso Idling Resource
    

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83. /
    public String getName();
    

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84. /
    public boolean isIdleNow();
    

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85. /
    public void registerIdleTransitionCallback(ResourceCallback callback);
    public interface ResourceCallback {
    public void onTransitionToIdle();
    }
    

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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();
    }
    }
    

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87. /
    Espresso + Dagger
    

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88. /
    Espresso + Dagger
    @Module
    class TestApplicationModule
    @Component(modules = [TestApplicationModule:class]
    interface TestApplicationComponent
    class TestApplication : Application
    

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89. /
    Espresso + Dagger
    @Provides fun sharedPref(context: Context): SharedPreferences {
    val pref = PreferenceManager.getDefaultSharedPreferences(context);
    pref.edit {
    clear()
    }
    return pref
    }
    

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90. /
    Espresso + Dagger
    @Provides @Singleton
    fun userRepository(): UserRepository {
    return mock()
    }
    

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91. /
    Espresso + Dagger
    interface TestAppComponent {
    //...
    fun userRepository(): UserRepository
    //...
    }
    

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92. /
    Espresso + Dagger
    class TestApplication {
    companion object {
    lateinit var appComponent: TestAppComponent
    }
    override fun onCreate() {
    super.onCreate()
    appComponent = //...
    }
    }
    

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93. /
    Espresso + Dagger
    val appComponent = TestApplication.appComponent
    whenever(appComponent.userRepository().login()).thenReturn(true)
    

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94. /
    Espresso + Dagger
    @Rule
    @JvmField
    val activityTestRule = ActivityTestRule(
    MainActivity::class.java,
    false,
    false
    )
    

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95. /
    Espresso + Dagger
    @Rule
    @JvmField
    val activityTestRule = ActivityTestRule(
    MainActivity::class.java,
    false,
    false
    )
    val activity = activityTestRule.launchActivity(null)
    

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96. Static Analysis
    /
    • Lint
    • PMD
    • Findbugs
    • Checkstyle
    

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97. Where do I start?
    /
    

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98. /
    • Write a test whenever app crash
    Where do I start?
    

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99. /
    • Write a test whenever app crash
    • Start writing in complex parts
    Where do I start?
    

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100. /
     • Write a test whenever app crash
     • Start writing in complex parts
     • Learn tools in free time
     Where do I start?
     

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101. Continuous Integration/Deployment
     /
     

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102. Recap
     /
     

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103. Have you met Test?
     nexlabs
     

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