Intro to Android Testing

Originally presented at DevFest Conakry 2018 in Guinea, West Africa.

https://www.meetup.com/Meetup-GDG-Conakry/events/253639851/

In this talk we'll cover why it's important to test your app, and the different types of testing frameworks available for Android including local unit tests, instrumentation tests, and Espresso.

Transcript

1. Intro to Android Testing
   Charles “Chuck” Greb
   @ecgreb
   DevFest Conakry
   December 1st, 2018
   

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4. • Software Engineer
   • Mobile applications since 2009
   • Mostly Android
   • Button
   About me
   

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5. Why test?
   

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6. • Verify code is correct
   • Prevent regressions
   • Documentation
   Why test?
   

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7. Testing Strategies
   

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8. • Don’t test
   • Manual
   • Automation
   Testing Strategies
   

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9. Types of Automated Tests
   

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10. • Unit
    • Integration
    • User Interface (UI)
    Types of Automated Tests
    

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11. Testing Pyramid
    https://martinfowler.com/bliki/TestPyramid.html
    

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12. Android Testing Pyramid
    

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15. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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16. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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17. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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18. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }
    }
    }
    

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19. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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20. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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21. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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22. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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23. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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24. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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25. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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26. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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27. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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28. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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29. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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30. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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31. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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32. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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33. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }_
    }+
    }+
    

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34. class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)
    val counter = Counter()
    counter_view.text = counter.reset().toString()
    count_button.setOnClickListener {
    counter_view.text = counter.count().toString()
    }+
    reset_button.setOnClickListener {
    counter_view.text = counter.reset().toString()
    }+
    }+
    }+
    

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35. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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36. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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37. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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38. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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39. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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40. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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41. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }_
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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42. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }_
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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43. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }_
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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44. class Counter {
    private var count = 0
    fun count(): Int {
    count++
    return count
    }+
    fun reset(): Int {
    count = 0
    return count
    }+
    }
    

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46. MainActivity
    

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47. MainActivity Counter
    

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48. MainActivity Counter
    

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49. MainActivity Counter
    

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50. MainActivity Counter
    CounterTest
    JUnit
    

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51. MainActivity Counter
    MainActivityTest CounterTest
    JUnit
    Instrumentation
    

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52. MainActivity Counter
    MainActivityTest CounterTest
    MainActivityUiTest
    JUnit
    Instrumentation
    Espresso
    

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53. Unit Tests
    JUnit
    

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54. class CounterTest {
    @Test
    fun shouldNotBeNull() {
    val counter = Counter()
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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55. class CounterTest {
    @Test
    fun shouldNotBeNull() {
    val counter = Counter()
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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56. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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57. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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58. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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59. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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60. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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61. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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62. class CounterTest {
    @Test+
    fun shouldNotBeNull() {
    val counter = Counter()+
    assertNotNull(counter)
    }+
    @Test
    fun reset_shouldReturnZero() {
    val counter = Counter()
    assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    

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63. assertEquals(0, counter.reset())
    }a
    @Test
    fun count_shouldIncrementNumber() {
    val counter = Counter()
    assertEquals(1, counter.count())
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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64. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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65. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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66. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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67. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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68. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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69. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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70. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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71. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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72. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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73. assertEquals(0, counter.reset())
    }a
    @Testc
    fun count_shouldIncrementNumber() {
    val counter = Counter()c
    assertEquals(1, counter.count())c
    assertEquals(2, counter.count())
    assertEquals(3, counter.count())
    }b
    @Test
    fun reset_shouldResetCounter() {
    val counter = Counter()
    counter.count()
    counter.count()
    counter.count()
    counter.reset()
    assertEquals(1, counter.count())
    }c
    }d
    

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75. Integration Tests
    Instrumentation
    

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76. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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77. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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78. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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79. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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80. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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81. @RunWith(AndroidJUnit4::class)
    class MainActivityTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    

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82. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }
    

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83. @Test+
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }
    

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84. @Test+
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }
    

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85. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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86. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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87. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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88. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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89. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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90. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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91. @Test
    fun shouldNotBeNull() {
    assertNotNull(activityTestRule.activity)
    }b
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }c
    @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    

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92. @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    @Test @UiThreadTest
    fun counterView_shouldDisplayZeroOnResetButtonClick() {
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.reset_button.performClick()
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }
    }
    

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93. @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    @Test @UiThreadTest
    fun counterView_shouldDisplayZeroOnResetButtonClick() {
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.reset_button.performClick()
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }+
    }-
    

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94. @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    @Test @UiThreadTest
    fun counterView_shouldDisplayZeroOnResetButtonClick() {
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.reset_button.performClick()
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }+
    }--
    

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95. @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    @Test @UiThreadTest
    fun counterView_shouldDisplayZeroOnResetButtonClick() {
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.reset_button.performClick()
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }+
    }-
    

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96. @Test @UiThreadTest+
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    activityTestRule.activity.count_button.performClick()+
    assertEquals("1", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("2", activityTestRule.activity.counter_view.text)
    activityTestRule.activity.count_button.performClick()+
    assertEquals("3", activityTestRule.activity.counter_view.text)
    }+
    @Test @UiThreadTest
    fun counterView_shouldDisplayZeroOnResetButtonClick() {
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.count_button.performClick()
    activityTestRule.activity.reset_button.performClick()
    assertEquals("0", activityTestRule.activity.counter_view.text)
    }+
    }-
    

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97. View Slide

98. UI Tests
    Espresso
    

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99. @RunWith(AndroidJUnit4::class)
    class MainActivityUiTest {
    @get:Rule
    val activityTestRule: ActivityTestRule =
    ActivityTestRule(MainActivity::class.java, false, false)
    @Before
    fun setUp() {
    activityTestRule.launchActivity(Intent())
    }a
    @Test
    fun counterView_shouldDisplayZeroOnCreate() {
    onView(withId(R.id.counter_view)).check(matches(withText("0")))
    }a
    @Test
    fun counterView_shouldDisplayNewCountOnCountButtonClick() {
    onView(withId(R.id.count_button)).perform(click())
    

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100. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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101. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test+
     fun counterView_shouldDisplayZeroOnCreate() {
     +onView(withId(R.id.counter_view)).check(matches(withText(“0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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102. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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103. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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104. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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105. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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106. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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107. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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108. @RunWith(AndroidJUnit4::class)
     class MainActivityUiTest {
     @get:Rule
     val activityTestRule: ActivityTestRule =
     ActivityTestRule(MainActivity::class.java, false, false)
     @Before
     fun setUp() {
     activityTestRule.launchActivity(Intent())
     }a
     @Test
     fun counterView_shouldDisplayZeroOnCreate() {
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }b
     @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     

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109. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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110. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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111. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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112. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())a
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())b
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())c
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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113. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())a
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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114. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())a
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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115. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())a
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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116. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())a
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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117. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.count_button)).perform(click())+
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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118. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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119. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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120. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }
     

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121. @Test
     fun counterView_shouldDisplayNewCountOnCountButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("1")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("2")))
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("3")))
     }a
     @Test
     fun counterView_shouldDisplayZeroOnResetButtonClick() {
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.count_button)).perform(click())
     onView(withId(R.id.reset_button)).perform(click())
     onView(withId(R.id.counter_view)).check(matches(withText("0")))
     }a
     }p
     

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122. View Slide

123. Demo
     

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124. Conclusion
     Testing is fun!
     

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125. • Why test?
     • Types of tests
     • Unit Tests
     • Integration Tests
     • UI Tests
     • Continuous Integration (CI)
     • Test-Driven Development (TDD)
     • Tests == Quality
     Conclusion
     

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126. Tests == Quality
     

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127. Merci
     Charles “Chuck” Greb
     @ecgreb
     DevFest Conakry
     December 1st, 2018
     

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128. usebutton.com
     

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