![[TestMethod]
public void GetTimeOfDay_At6AM_ReturnsMorning()
{
try
{
// Setup: change system time to 6 AM
...
// Arrange phase is empty: testing static method, nothing to initialize
// Act
string timeOfDay = GetTimeOfDay();
// Assert
Assert.AreEqual("Morning", timeOfDay);
}
finally
{
// Teardown: roll system time back
...
}
}](https://image.slidesharecdn.com/testersguidetounittesting-letstest-191215162509/85/Testers-guide-to-unit-testing-29-320.jpg)
![Another
Example
package com.acme.pizza
import scala.collection.mutable.ArrayBuffer
class Pizza {
private val toppings = new ArrayBuffer[Topping]
def addTopping (t: Topping) { toppings += t}
def removeTopping (t: Topping) { toppings -= t}
def getToppings = toppings.toList def boom { throw
new Exception("Boom!") }
}
package com.acme.pizza
case class Topping(name: String)](https://image.slidesharecdn.com/testersguidetounittesting-letstest-191215162509/85/Testers-guide-to-unit-testing-31-320.jpg)
Testers guide to unit testing
- 1. A Tester’s Guide to Unit Testing https://github.com/CraigRisiAG
- 2. About Me
- 3. Agenda 1. Why 2. What 3. How
- 8. Reducing Duplication Req: Any number entered into the text box between 1-10 must provide a valid response Alphanumeric, spaces, etc.
- 9. Reducing Duplication What if your code was as follows: Int i= convert.ToInt32(txtMyTextBox.Text) If i >= 1 and i <= 10 Print (“Valid”) Else Print (“Invalid”)
- 11. Documenting code and improved traceability
- 13. What Should be Unit Tested Entry and exit points Isolated functionality Boundary value validations Clear data permutations Security and performance
- 14. Good Unit Tests FAST ISOLATED REPEATABLE SELF- CHECKING TIMELY
- 15. Aspects of Unit Testing Test Set Up Mocking Assertions Runners Reporting and Results
- 16. Naming Your Tests - Requirement - Method / Cass under test - Expected Result - Input or State Map_DefaultConstructorShouldCreateEmptyGisMap() ShouldAlwaysDelegateXMLCorrectlyToTheCustomHand lers() Dog_Object_Should_Eat_Homework_Object_When_Hung ry()
- 17. Arranging Your Tests Arrange your objects, by creating and setting them up in a way that readies your code for the intended test Act on an object Assert that something is as expected
- 18. Write Minimally Passing Tests FOCUS ON BEHAVIOUR AND NOT JUST COVERAGE
- 22. How
- 23. Types of Assertions assertArrayEquals() assertEquals() assertTrue() + assertFalse() assertNull() + assertNotNull() assertSame() + assertNotSame() assertThat()
- 24. Matchers Core any() Matches anything is() A matcher that checks if the given objects are equal. describedAs() Adds a descrption to a Matcher Logical allOf() Takes an array of matchers, and all matchers must match the target object. anyOf() Takes an array of matchers, and at least one of the matchers must report that it matches the target object. not() Negates the output of the previous matcher. Object equalTo() A matcher that checks if the given objects are equal. instanceOf() Checks if the given object is of type X or is compatible with type X notNullValue() + nullValue() Tests whether the given object is null or not null. sameInstance() Tests if the given object is the
- 25. Testing For Exceptions @Test(expected = IllegalArgumentException.class) public void testForExceptions1() { MyUnit myUnit = new MyUnit(); myUnit.throwIllegalArgumentException(); } @Test public void testForExceptions2() { MyUnit myUnit = new MyUnit(); try{ myUnit.throwIllegalArgumentException(); fail("expected IllegalArgumentException"); } catch(IllegalArgumentException e){ //ignore, this exception is expected. }
- 26. Stubs, Mocks, and Proxies unit test --> stub unit test --> unit --> stub unit test asserts on results and state of unit unit test --> mock unit test --> unit --> mock unit test asserts on result and state of unit unit test asserts on the methods called on mock unit test --> collaborator unit test --> proxy unit test --> unit --> proxy --> collaborator unit test asserts on result and state of unit unit test asserts on methods called on proxy
- 28. public static string GetTimeOfDay() { DateTime time = DateTime.Now; if (time.Hour >= 0 && time.Hour < 6) { return "Night"; } if (time.Hour >= 6 && time.Hour < 12) { return "Morning"; } if (time.Hour >= 12 && time.Hour < 18) { return "Afternoon"; } return "Evening"; }
- 29. [TestMethod] public void GetTimeOfDay_At6AM_ReturnsMorning() { try { // Setup: change system time to 6 AM ... // Arrange phase is empty: testing static method, nothing to initialize // Act string timeOfDay = GetTimeOfDay(); // Assert Assert.AreEqual("Morning", timeOfDay); } finally { // Teardown: roll system time back ... } }
- 30. public void GetTimeOfDay_For6AM_ReturnsMorning() { // Arrange phase is empty: testing static method, nothing to initialize // Act string timeOfDay = GetTimeOfDay(new DateTime(2015, 12, 31, 06, 00, 00)); // Assert Assert.AreEqual("Morning", timeOfDay); }
- 31. Another Example package com.acme.pizza import scala.collection.mutable.ArrayBuffer class Pizza { private val toppings = new ArrayBuffer[Topping] def addTopping (t: Topping) { toppings += t} def removeTopping (t: Topping) { toppings -= t} def getToppings = toppings.toList def boom { throw new Exception("Boom!") } } package com.acme.pizza case class Topping(name: String)
- 32. package com.acme.pizza import org.scalatest.FunSuite import org.scalatest.BeforeAndAfter class PizzaTests extends FunSuite with BeforeAndAfter { var pizza: Pizza = _ before { pizza = new Pizza } test("new pizza has zero toppings") { assert(pizza.getToppings.size == 0) } test("adding one topping") { pizza.addTopping(Topping("green olives")) assert(pizza.getToppings.size === 1) } // mark that you want a test here in the future test ("test pizza pricing") (pending) }
- 34. Questions