Practical Session No. 8 - CppUnit

Size: px

Start display at page:

Download "Practical Session No. 8 - CppUnit"

Mabel Hoover
6 years ago
Views:

1 Practical Session No. 8 - CppUnit Window, a step by step example Contents 1) Setting up your project (VC++) 2) Setting up your project (Linux) 3) The Main Program 4) Adding Tests: a) Retrieving Parameters b) Moving of Window Center c) Changing Width and Height Setting up your project (VC++) Compiling and installing CppUnit libraries The detailed description how to set your VC++ CppUnit resides at

2 In the following document, CPPUNIT is the directory where you unpacked CppUnit. It contains the directories: INCLUDE for.h files, LIB for libraries, SRC for source code etc. Before using CppUnit you need to compile CppUnit libraries; do this as follows: Open the CPPUNIT/src/CppUnitLibraries.dsw workspace in VC++. In the 'Build' menu, select 'Batch Build...' In the batch build dialog, select all projects and press the build button. The resulting libraries can be found in the CPPUNIT/lib/ directory. Once it is done, you need to let VC++ know where are the CppUnit header files and the CppUnit libraries to use them in your VC++ project note that CppUnit is not a standard library and therefore the paths to its headers and libraries are not configured Open the 'Tools/Options...' dialog, and in the 'Directories' tab, select 'include files' in the combo menu. Add a new entry that points to CPPUNIT/include/. Change to 'libraries files' in the combo and add a new entry for CPPUNIT/lib/. Repeat the process with 'source files' and add new entry CPPUNIT/src/cppunit/. Getting started Creates a new console application ('a simple application' template will do). Let's link CppUnit library to our project. In the project settings: In tab 'C++' select the combo menu 'Code generation', set the combo to 'Multithreaded DLL' for the release configuration, and 'Debug Multithreaded DLL' for the debug configure, In tab 'C++', select the combo menu 'C++ language', for All Configurations, check 'enable Run-Time Type Information (RTTI)',

3 In tab 'Link', in the 'Object/library modules' field, add cppunitd.lib for the debug configuration, and cppunit.lib for the release configuration. The CppUnit program will return 0 if all tests passed successfully, otherwise it returns the positive number n >=1 in case of error. Also, all errors are printed. You should not modify main, is serves like a "driver" for all CppUnit tests. Find environments which generate CppUnit code skeletons (main function and definitions like CPPUNIT_TEST ( )) it is a very unpleasant task so software developers may present CppUnit generators to the market. The compiler messages and the application's output is now in the build window Setting up your project (Linux) First of all, you may read the excellent guideline about how to use CppUnit on various versions of Unix: Let's assume our project consists of the following files: 1) The class being tested Window.cpp (the header file is Window.h) 2) The class containing CPPUNIT tests WindowTest.h (is implemented in WindowTest.cpp) 3) The file with main cpputest.cpp The following makefile will help us to compile the application: COMPILER = g++ cpputest : cpputest.o Window.o WindowTest.o g++ -o $@ cpputest.o Window.o WinTest.o lcppunit -ldl cpputest.o : cpputest.cpp Window.h WinTest.h $(COMPILER) o $@ -c cpputest.cpp

4 Window.o : Window.cpp Window.h WinTest.h $(COMPILER) o $@ -c Window.cpp WinTest.o : WinTest.cpp Window.h WinTest.h $(COMPILER) o $@ -c WinTest.cpp On your home Linux installations, make sure that the directories for CppUnit include files and libraries are installed properly. At the campus Linux system, CppUnit is installed properly and all the installation steps become irrelevant. Configuring Linux CppUnit installation at home: If a compiler complains it cannot find CppUnit include files, update the makefile instead of COMPILER=g++, set: COMPILER=g++ -I/users/studs/msc/binun/CppUnit/include This setting will be applied if I were installed CppUnit on my Linux account. I tells the g++ compiler where the header files of a new nonstandard package (like CppUnit) reside. If a compiler complains it cannot find CppUnit libraries, in the first row of makefile (where linking is performed), run: COMPILER=g++ -L/users/studs/msc/binun/CppUnit/lib o $@ cpputest.o Window.o WinTest.o -lcppunit -lcppunitrunner This setting tells the g++ linker where the libraries of a new nonstandard packegs (like CppUnit) reside. The main program The main function just sets the environment for running CppUnit tests. Our function is to write the class to be tested and the tests in our case, Window.h and Window.cpp represent the class Window to be tested; WinTest.h and WinTest.cpp

5 represent the tests. To make the tests available to CppUnit library, two things should be made: 1) The definition of WindowTest class should be enclosed in CPP_TEST_SUITE ( WindowTest ) CPP_TEST_SUITE_END. Between these macros, there should be several CPP_TEST ( ) macros one for each method of WindowTest 2) At the start of WindowTest.cpp there should be CPP_SUITE_TEST_REGISTRATION (WindowTest). This ensures that WindowTest class will be put into CppUnit test registry and picked by the first expression of main. The test suite picked from the test registry is loaded into CppUnit Runner object (runner.addtest (suite)). Runner is configured to direct its output (error messages due to false tests) to standard error output (console). Runner is executed using run() method. All error messages are printed; the number of false tests is returned in wassuccessful. cpputest.cpp #include <cppunit/compileroutputter.h> #include <cppunit/extensions/testfactoryregistry.h> #include <cppunit/ui/text/testrunner.h> int main(int argc, char* argv[]) // Get the top level suite from the registry CppUnit::Test *suite = CppUnit::TestFactoryRegistry::getRegistry().makeTest(); // Adds the test to the list of test to run CppUnit::TextUi::TestRunner runner; runner.addtest( suite ); // Change the default outputter to a stderr runner.setoutputter( new CppUnit::CompilerOutputter( &runner.result(), std::cerr ) ); // Run the tests. bool wassuccessful = runner.run(); // Return error code 1 if the one of test failed. return wassuccessful? 0 : 1; On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest.

6 Our application will report that everything is fine and no tests were run. So let's add some tests... Creating the Empty Window Class For this example, we are going to write a simple Window class. A window has a center, width and height: Window.h class Window private: int centerx,centery; int height,width; public: void getcenter (int&, int&); void getdimensions(int&, int&); Window(int, int, int, int); void move (int, int); ; Window.cpp #include "Window.h" void Window::getCenter (int& cx, int& cy) void Window::getDimensions(int& h, int& w) Window::Window(int cx, int cy, int h, int w) void Window::move (int byx, int byy) Let's begin by creating a test class where we can put our tests, and add single test to test retrieving of Window attributes initialized by the constructor WindowTest.h: #ifndef WINTEST_H #define WINTEST_H #include <cppunit/extensions/helpermacros.h> #include "Window.h" class WindowTest: public CppUnit::TestFixture CPPUNIT_TEST_SUITE(WindowTest); CPPUNIT_TEST( testretrieve ); CPPUNIT_TEST_EXCEPTION( testchangesize, WindowBorderException ); CPPUNIT_TEST( testmove ); CPPUNIT_TEST( testintersect ); CPPUNIT_TEST_SUITE_END(); private:

7 Window *w1,*w2; public: void setup(); void teardown(); void testretrieve(); void testchangesize (); void testmove (); ; #endif // WINTEST_H CPPUNIT_TEST_SUITE declares that our Fixture's test suite. CPPUNIT_TEST adds a method to our test suite. The test is implemented by the method named testretrieve(). setup() and teardown() are used to setup/teardown some fixtures. We are not using any for now. WindowTest.cpp #include "WindowTest.h" // Registers the fixture into the 'registry' CPPUNIT_TEST_SUITE_REGISTRATION( WindowTest ); void WindowTest::setUp() w1 = new Window (50,50,30,20); w2 = new Window (30,30,10,10); void WindowTest::tearDown() delete w1; delete w2; Void WindowTest::testRetrieve () Void WindowTest::testChangeSize() Void WindowTest::testMOve () On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest. all tests pass, since they are empty.

8 Retrieving of Window Parameters Let's write our first real test. A test is usually composed of three parts: setting up data used by the test doing some processing based on those data checking the result of the processing void WindowTest::testRetrieve() int cx,cy; w1->getcenter(cx,cy); CPPUNIT_ASSERT_EQUAL(30,cx); CPPUNIT_ASSERT_EQUAL(20,cy); Well, we finally have a good start of what our Window class will look likes. Let's start implementing... Window.h class Window private: int centerx,centery; int height,width; public: void getcenter (int& cx, int& cy) cx = centerx; cy = centery; void getdimensions(int& h, int& w) h = height; w = width; ; Window(int cx, int cy, int h, int w) centerx = cx; centery = cy; height = h; width = w; void move (int byx, int byy)

9 On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest. Moving of Window Center Now we want to add moving capabilities to Window. The center of the window should be moved. Note that the borders of a window should not cross the borders of the screen; if this happens, the center must remain the same. That is, the first test should pass, while the second one fail. void WindowTest::testMove () int cx,cy; w2->move (-10,-10); w2->getcenter (cx,cy); CPPUNIT_ASSERT_EQUAL(20,cx); CPPUNIT_ASSERT_EQUAL(20,cy); w1->move(35,20); int cx1, cy1; w1->getcenter(cx1, cy1); CPPUNIT_ASSERT_EQUAL(85,cx1); CPPUNIT_ASSERT_EQUAL(70,cy1); On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest Now let's implement the required functionality: void Window::move (int byx, int byy) int top = centery + byy + height, bottom = centery + byy - height, right = centerx + byx + width, left = centerx + byx - width; if (top <= SCRHEIGHT && bottom >=0 && right <= SCRWIDTH && left >=0) centerx+=byx; centery+=byy;

10 On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest Changing Width and Height Now let's add the capability for changing size by some factor. The center should not move; the borders will expand (or shrink, if the factor < 1). We must ensure that the new borders do not exceed the screen borders. In contrast to move (), if a border is exceeded, not only the original height and width must remain the same, but also the exception should be thrown. The tests would look like: void WindowTest::testChangeSize () int w,h; w2->enlarge(2); w2->getdimensions(w,h); CPPUNIT_ASSERT_EQUAL(20,w); CPPUNIT_ASSERT_EQUAL(20,h); w1->enlarge(2); //throws an exception... Here w2 will change the dimensions; its width and height will be (20,20). The size of w1 will be (60,40); since the center is in (50,50), the screen border will be exceeded and the exception will be thrown. Let's implement the needed functionality: void Window::enlarge (int factor) int top = centery + height*factor, bottom = centery - height*factor, right = centerx + width*factor, left = centerx - width*factor; if (top <= SCRHEIGHT && bottom >=0 && right <= SCRWIDTH && left >=0) width = width*factor; height = height*factor; else throw new WindowException; On VC++, select Build Project (F7) to compile this file. On Linux, run the command make the makefile will run all compilation and linking steps. Then run cpputest Homework (the deadline is , 24.00)

11 In this homework you will be asked to extend the example given in this practice session. You should submit the archive including: a) Makefile b) Window.cpp, Window.h - the implementation of Window class c) WindowTest.cpp, WindowTest.h - tests d) Cpputest.cpp main Your example should run in Linux. 1) The policy to change the window size in our example is implemented according to the principle "if you cannot increase the window sizes by factor 2, don't increase it at all and throw exception". However, you may increase the width and the height by the factor f smaller than required (say, 1.5) so that the window does not yet exceed the screen border. Increasing the size by the factor greater than f already leads to exceeding the screen border. We will call such f the maximal increase factor. Implement the method void Window::weak_enlarge (int factor) which tries to increase the size of a window by factor. If the resulting window exceeds the screen border, weak_enlarge computes the maximal increase factor f and increase the size of the given window by f. Write tests 2) Implement the method void Window::rotate () which rotates the window on 90 degrees (in fact, exchanges width and height). Write tests 3) Implement the method int Window::intersect (const Window &w) which checks whether the surfaces of the given window and w intersect (return 1 if yes, otherwise 0). 4) Configure the CppUnit test environment. Compile and run

Basic Design of CppUnit

Basic Design of CppUnit C++ Object Oriented Programming Pei-yih Ting NTOUCS 32-1 Structurally, this is a Composite pattern. TestLeaf Test TestComposite Each TestCase is a single test. Each TestComposite