Software Development Tools

COMP220Seb Coope

Week 8 Lecture 1Ant, Testing and JUnit (2)

These slides are mainly based on “Java Development with Ant” - E. Hatcher & S.Loughran. Manning Publications, 2003 and “JUnit in Action”, 2nd edition – P. Tahchiev, F. Leme, V. Massol, G. Gregory, Manning Publications, 2011

JUnit Primer (with ANT) continued

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More on writing a test case

Recall that a test case is a class which imports some JUnit

packages import org.junit.Test; import static org.junit.Assert.*;

... and implements one or more no-

argument void @Test methods testXXX()

(See 11. Ant, Testing and JUnit, JUnit Primer, Slides 5, 6.)

where each testXXX() consists of several assertion methods typically comparing expected and actual values.

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More on writing a test case: setUp() and tearDown()

Additionally, to prevent one @Test method from affecting the behaviour of another we can a. annotate by @Before and implement a method public void setUp() which

- initializes objects under test - by storing a state (fixture) as member variables to the

test case

b. Optionally, annotate by @After and implement a method

public void tearDown() which - releases objects/resources under test.

c. For this to work, we also need to import from Junit: import org.junit.Before; import org.junit.After;The names setUp and tearDown are traditional after JUnit3.

JUnit4 annotations @Before and @After make the behaviour of setUp and tearDown as required. (See also next slides.)

Running a test case with setUp() and tearDown()

Test Runner calls the same setUp() and tearDown() methods before and after each @Test method testXXX() is invoked.

Thus, each @Test method testXXX() runs under one and the same fixture created by

setUp()(despite this fixture could probably be changed by other test methods testYYY()),

hence, with no assumptions about the order in which test methods are called.

This prevents one test from affecting the behaviour of another.

The following example illustrates this behaviour by using System.out.println("some message").

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Test Case setUpTearDownTest.java :package org.example.antbook.junit;

//import JUnit4 classes:

import static org.junit.Assert.*;

import org.junit.Test; //

import org.junit.Before; //import org.junit.* also would work

import org.junit.After; //

public class setUpTearDownTest{

@Before //Runs before each @Test method

public void setUp(){ System.out.println("setUp sets up a fixture"); }

@After //Runs after each @Test method

public void tearDown(){ System.out.println("tearDown releases fixture"); }

@Test

public void testA(){

System.out.println("testA runs");

assertTrue("MULTIPLICATION FAILED!!!", 4 == (2 * 2));

}

@Test //Each method annotated by @Test runs

public void testB(){

System.out.println("testB runs");

assertSame("ADDITION FAILED!!!", 4, 2 + 2);

}

public void SomeTestC(){

System.out.println("SomeTestC runs");

assertSame("ADDITION FAILED!!!", 5, 2 + 2);

}

}

Should it fail/run ???

Put this file under ch04\test according to the package declaration.Use your personalised package name!

Here setUp() and tearDown() methods do nothing besides informing that what they intend to do.

@Test methods

Compile and Run:C:\Antbook\ch04>javac -d build\test test\org\example\antbook\junit\setUpTearDownTest.java

C:\Antbook\ch04>java -cp build\test;C:\JAVA\junit4.8.2\junit-4.8.2.jar org.junit.runner.JUnitCore org.example.antbook.junit.setUpTearDownTestJUnit version 4.8.2.setUp sets up a fixturetestA runstearDown releases fixture.setUp sets up a fixturetestB runstearDown releases fixture

Time: 0.016OK (2 tests)

Do not forget to recompile each time!!!

Note that someTestC was not run, unlike testA and testB! WHY??Because only @Test annotated methods should be run by Junit4 test runners. testA() and testB(), succeeded, so, setUpTearDownTest succeeded too (OK).Replace 4 by 5 in testA() and recompile and run it again. What will be changed? Will setUpTearDownTest succeed?

setUp and tearDown surround each @Test annotated method.

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Compile and Run:

C:\Antbook\ch04>java -cp build\test;C:\JAVA\junit4.8.2\junit-4.8.2.jar org.junit.runner.JUnitCore org.example.antbook.junit.setUpTearDownTestJUnit version 4.8.2.setUp sets up a fixturetestA runstearDown releases fixtureE.setUp sets up a fixturetestB runstearDown releases fixture

Time: 0.015There was 1 failure:1) testA(org.example.antbook.junit.setUpTearDownTest)java.lang.AssertionError: MULTIPLICATION FAILED!!! <many lines skipped>FAILURES!!!Tests run: 2, Failures: 1

Do not forget to recompile each time!!!

E means that the previous testA failed

Your message to yourself

Add @Test annotation before someTestC, and compile and run it again.What will be the result?Finally, compile and run this by Ant from mybuild.xml like in Part 11, Slide 14.

Writing a Test SuiteWhat if we need to run many JUnit test cases?

JUnit, test classes can be grouped into a suite

Just use appropriate JUnit imports and annotations

@SuiteClasses

and

@RunWith(value=Suite.class).

Grouping tests lets you build several individual test cases for a

particular subsystem , and

write an all-inclusive Test Suite that runs them all .

See AllTests.java below.

Note that Suite of Suites can also be created in the same way.

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An example of a Test Suite

package org.example.antbook;

import org.junit.runner.RunWith;import org.junit.runners.Suite;import org.junit.runners.Suite.SuiteClasses;

@RunWith(value=Suite.class)@SuiteClasses(value={org.example.antbook.junit.SimpleTest.class, org.example.antbook.junit.setUpTearDownTest.class,org.eclipseguide.persistence.FilePersistenceServicesTest.class})public class AllTests{}

C:\Antbook\ch04\test\org\example\antbook\AllTests.java

Test Suite to run test methods of three test cases: SimpleTest, setUpTearDownTest and FilePersistenceServicesTest. We can also compose suites of suites in the same way.

EXTEND target junit-TestRunner in mybuild.xml to RUN test suite AllTests.java.

End of file

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Test Suites and Ant??

Don’t need to bother with test suites when running JUnit tests using Ant:

· Ant itself can list a group of TestCase classes in a much more powerful way – all test cases from a directory(!), and

· run it as a batch from the build file itself.

· But <java> task is not appropriate for this purpose.

The JUnit task<junit>

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The JUnit task <junit>The Ant's task <junit> is much better for running

JUnit test cases than <java> which we used till this point:

<junit> runs one or more (even all from a directory) JUnit test cases

Collects and displays test results in one or more formats

Provides a way either to fail or continue a build when a test fails

Recall the unnatural situation when BUILD SCCESSFUL while some tests failed.

No need to mention explicitly any Test Runner (as it was necessary with <java> task)

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The JUnit task <junit> (cont.)

<target name="test-brief" depends="test-compile">

<junit>

<classpath refid="test.classpath"/>

<test name = "org.eclipseguide.persistence.FilePersistenceServicesTest"/>

<test name="org.example.antbook.junit.SimpleTest"/>

</junit>

</target>

Extend mybuild.xml by this target. You can also add:<test name="org.example.antbook.junit.setUpTearDownTest"/>

<classpath> with id test.classpath formerly used for running test cases by <java> and some <javac> tasks

In order to execute some existing test cases by Ant, let us declare a special <junit> task with

the names of the test cases and appropriate classpath :

One or more test cases to run

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The JUnit task <junit> (cont.)

TRY it:

H:\Antbook\ch04>ant -f mybuild.xml test-brief

Buildfile: C:\Antbook\ch04\mybuild.xml

[SOME MESSAGES OMITTED]

test-brief:

[junit] Test org.eclipseguide.persistence.

FilePersistenceServicesTest FAILED

BUILD SUCCESSFUL

<junit> TEST FAILED, but BUILD SUCCESSFUL (?!)It would be more natural to see here also BUILD FAILED...But let us wait for a more advanced build with <junit>.Nothing above about org.example.antbook.junit.SimpleTest because it does not fail. TRY to confirm this by appropriate experiment.

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The JUnit task <junit> (cont.) Test failure enforcing build failure

There are two issues to note about these results: 1. no details were provided about which

testXXX() method in FilePersistenceServicesTest failed and why, not so bad – no cluttering messages, But, on the other hand, insufficiently informative

2. the build completed successfully (?!) despite the test failure – looks not natural.

However, ADD to the task <junit> two attributes: <junit haltonfailure="false" printsummary="true">

We now get more informative and coherent output:

(a default value)

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The JUnit task <junit> (cont.) Test failures enforcing build failures

test-brief: [junit] Running org.eclipseguide.persistence.FilePersistenceServicesTest [junit] Tests run: 5, Failures: 2, Errors: 0, Time elapsed: 0.031 sec [junit] Test org.eclipseguide.persistence.FilePersistenceServicesTest FAILED [junit] Running org.example.antbook.junit.SimpleTest [junit] Tests run: 1, Failures: 0, Errors: 0, Time elapsed: 0.016 secBUILD SUCCESSFULTotal time: 1 second

• printsummary="true" prints one-line statistics for each test case. • Taking haltonfailure="true" gives results only up to the first failure:

test-brief: [junit] Running org.eclipseguide.persistence.FilePersistenceServicesTest [junit] Tests run: 5, Failures: 2, Errors: 0, Time elapsed: 0.031 secBUILD FAILEDC:\Antbook\ch04\mybuild.xml:140: Test org.eclipseguide.persistence.FilePersistenceServicesTest failed

Now BUILD FAILED because of first failing test case(!!)

Now it is more informative:

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Structure directories to accommodate testingSee also Part 11, slide 13

Recall and extend the directory structure in ch04:

C:\Antbook\ch04 - base directory (basedir= ".")

C:\Antbook\ch04\src - source directory (${src.dir})

C:\Antbook\ch04\test - test directory (${src.test.dir})

containing (deeper) JUnit test classes

C:\Antbook\ch04\build - build directory (${build.dir})

C:\Antbook\ch04\build\classes - for compiled source files

(${build.classes.dir})

C:\Antbook\ch04\build\test - for compiled JUnit test cases

(${build.test.dir} )

C:\Antbook\ch04\build\data - for test repots in XML format

C:\Antbook\ch04\build\report - for test repots in HTML format

(new directories data and report to be considered later)

First 3 red coloured directories and their contents are created by yourself.

Other directories should be created automatically by your Ant build file.

Four main steps to do in Ant build file related to JUnit testing

Adding testing into our build process is straightforward: Add a few targets or tasks:

1. target test-init to initialize (<mkdir>) the testing directory structure (except directories created by yourself manually; these are last three directories on the previous slide),

2. target test-compile to compile the test code with <javac>,

3. target test (or the like) to execute the tests with <junit> (or <java>),

4.<junitreport> and <report> tasks to generate the test reports (to be considered later).

Note that besides testing we need as usually also steps and targets dealing with source code in src not mentioned above.

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Ant build process related to JUnit testingSome more details

<property name="src.dir" value="src"/>

<property name="src.test.dir" value="test"/>

<property name="build.dir" location="build"/> More properties...

Before above four steps, we should start with assigning properties to various directories used by our (compile and) test targets:

C:\Antbook\ch04\build

C:\Antbook\ch04\src

C:\Antbook\ch04\test

Benefits of presentation of directories by properties:

If you want to change your system of directories, this can be done only in one place of build file.

Benefits of presentation of directories by properties:

Also, we can easily control e.g. where Ant places test reports by overriding test.reports.dir in command line

as

-Dtest.reports.dir=C:\REPORTS

to temporary change the standard (default) behaviour described in our Ant build file.

Thus, in mybuild.xml you should present all directories by properties

(except those directories related to package declarations which you create manually for your source files and test cases and need not mention in mybuild.xml)!

Ant build process related to JUnit testingSome more details

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<path id="test.classpath"> <pathelement location="${build.test.dir}"/> <!-- build/test --> <pathelement location="C:\JAVA\junit4.8.2\junit-4.8.2.jar"/> <pathelement location="${build.classes.dir}"/> <!-- build/classes --></path>

For compiling and running source files and tests cases we need classpath which has been already introduced into mybuild.xml in

11. Ant, Testing and JUnit , Slides 14 and 29 (and repeated now):

Ant build process related to JUnit testingSome more details

CHECK all targets, tasks, properties and paths in mybuild.xml required for running test-brief target (and for other future test targets).

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In mybuild.xml, testing can possibly be preceded by a <copy> task

This brings over all non-.java resources: For example, assume that an html file is required as an

argument of a Java program which should do something with this file (read it, parse it, search some information in it, etc).

Then we need an example of such file test.html somewhere under C:\Antbook\ch04\test , and so

test.html, should be copied into the ${build.test.dir}, to allow our compiled JUnit test cases to access test data file – test.html – easily .

<copy todir="${build.test.dir}"><fileset dir="${src.test.dir}" excludes="**/*.java,**/*.class"/></copy>

C:\Antbook\ch04\build\test

C:\Antbook\ch04\test

Ant build process related to JUnit testingSome more details