Introduction to Unit Testing using NUnit 2.0

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Introduction to Unit Testing using NUnit 2.0
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NUnit V2.0

• NUnit 2.0
• Unit testing framework for .NET
• Open source, written in C
• http//www.nunit.org/
• Mainly for component/server-side testing
• Not for GUI testing
• Assert-driven testing

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NUnit Demo

• Click Payroll.exe
• Click Run
• Green bar means code is clean
• Rerun unit tests after code changes

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Starting NUnit

• Nunit has both GUI and console interfaces
• NUnit Tutorial http//www.conestogac.on.ca/mtanu
  an/winoop03/tutorials/NunitTutorial.htm
• NUnit Guide http//www.conestogac.on.ca/mtanuan/
  winoop03/assignments/NunitGuideToAssignments.htm

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Nunit-gui.exe.config

• In the config file C\Program Files\NUnit
  V2.0\bin\nunit-gui.exe.config
• Add startup option for .NET v1.1
• Otherwise, Error Invalid PInvoke Metadata Format
• lt?xml version"1.0" encoding"Windows-1252"?gt
• ltconfigurationgt
• ltstartupgt ltsupportedRuntime version"v1.1.4322"
  /gt lt/startupgt
• ltappSettingsgt
• lt!-- User application and configured
  property settings go here.--gt
• lt!-- Example ltadd key"settingName"
  value"settingValue"/gt --gt
• ltadd key"toolTip.ShowAlways" value"False"
  /gt
• ltadd key"shadowfiles.path"
  value"temp\nunit20\ShadowCopyCache" /gt
• lt/appSettingsgt
• lt/configurationgt

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Sample Unit Test Code

• TestFixture
• public class EmployeeTypePDTest
• // instance variables
• private EmployeeTypePD testEmployeeTypePD
• private Random randomNumber new Random()
• public void TestConstructor()
• string expected, actual
• // test constructor with parameters
• int id 101 string desc "My Employee"
• double min 6.50 double max 10.50
• expected id.ToString()descmin.ToString()max
  .ToString()
• // call the constructor method
• testEmployeeTypePD new EmployeeTypePD(id,
  desc, min, max)
• // get and compare
• actual testEmployeeTypePD.GetEmployeeTypeId().
  ToString()
• testEmployeeTypePD.GetDescription()

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NUnit Attributes

• TestFixture
• Public class that contains test methods
• Test
• Public void method without parameters
• Contains the test case code
• Optional
• Others (not required for Assignment 3)
• SetUp
• TearDown
• ExpectedException
• Ignore

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Unit Testing Coding Tips

• Method Call Coverage
• All public methods must be called at least once
• Indirect calls allowed
• E.g., EmployeeTypePD.Find() calls
  EmployeeTypeDA.Find()
• Assertions
• Use AssertEquals(string, object, object) method
• Consider use of Random class
• Advanced (not in Assignment 3)
• Check boundary conditions and failure scenarios
  (forced-error tests)

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Test Suite with Varied Inputs

• To run the same test case methods with varied
  inputs.
• Create abstract class that contains all the test
  case methods
• Add a method to accept and set the input values
• Create child classes that sets varied input
  values.