1                    How to write unit tests for wxWidgets
2                    =====================================
3
4 Unit tests for wxWidgets are written using small cppunit framework. To compile
5(but not to run) them you need to have it installed. Hence the first part of
6this note explains how to do it while the second one explains how to write the
7test.
8
9I. CppUnit Installation
10-----------------------
11
121. Get it from http://www.sourceforge.net/projects/cppunit
13   (latest version as of the time of this writing is 1.8.0)
14
152. Build the library:
16 a) Under Windows using VC++ (both versions 6 and 7 work):
17    - build everything in CppUnitLibraries.dsw work space
18    - add include and lib subdirectories of the directory
19      where you installed cppunit to the compiler search path
20      using "Tools|Options" menu in VC IDEA
21
22 b) Under Unix: run configure && make && make install as usual
23
24
25II. Writing tests with CppUnit
26------------------------------
27
281. Create a new directory tests/foo
29
302. Write a cpp file for the test copying, if you want,
31   from one of the existing tests. The things to look for:
32 a) #include "wx/cppunit.h" instead of directly including CppUnit headers
33 b) don't put too many things in one test case nor in one method of a test
34    case as it makes understanding what exactly failed harder later
35 c) 'register' your tests as follows so that the test program will find and
36    execute them:
37
38    // register in the unnamed registry so that these tests are run by default
39    CPPUNIT_TEST_SUITE_REGISTRATION(MBConvTestCase);
40
41    // also include in it's own registry so that these tests can be run alone
42    CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(MBConvTestCase, "MBConvTestCase");
43
44   Read CppUnit documentation for more.
45
463. add a '<sources>' tag for your source file to tests/test.bkl
47
48
49III. Running the tests
50----------------------
51
521. Regenerate the make/project files from test.bkl using bakefile_gen, e.g.:
53        cd build/bakefiles
54        bakefile_gen -b ../../tests/test.bkl
55   and if you're on a unix system re-run configure.
56
572. Build the test program using one of the make/project files in the tests
58   subdirectory.
59
603. Run the test program with no arguments to run the default set of tests
61   (which are all those registered with CPPUNIT_TEST_SUITE_REGISTRATION).
62   Or to list the test suites without running them:
63      test -l
64
654. Tests that have been registered under a name using
66   CPPUNIT_TEST_SUITE_NAMED_REGISTRATION can also be run separately. For
67   example:
68      test MBConvTestCase
69   or to list the tests:
70      test -L MBConvTestCase
71
725. Fault navigation.
73   VC++ users can run the programs as a post build step (Projects/Settings/
74   Post-build step) to see the test results in an IDE window. This allows
75   errors to be jumped to in the same way as for compiler errors, for
76   example by pressing F4 or highlighting the error and pressing return.
77   
78   Similarly for makefile users: makefiles can be modified to execute the
79   test programs as a final step. Then you can navigate to any errors in the
80   same way as for compiler errors, if your editor supports that.
81
82   Another alternative is to run the tests manually, redirecting the output
83   to a file. Then use your editor to jump to any failures. Using Vim, for
84   example, ':cf test.log' would take you to the first error in test.log, and
85   ':cn' to the next.
86
87   If you would like to set a breakpoint on a failing test using a debugger,
88   put the breakpoint on the function 'CppUnit::Asserter::fail()'. This will
89   stop on each failing test.
90
91
92IV. Notes
93---------
94
951. You can register your tests (or a subset of them) just under a name, and not
96   in the unnamed registry if you don't want them to be executed by default.
97
982. If you are going to register your tests both in the unnamed registry
99   and under a name, then use the name that the tests have in the 'test -l'
100   listing.
101
1023. Tests which fail can be temporarily registered under "fixme" while the
103   problems they expose are fixed, instead of the unnamed registry. That
104   way they can easily be run, but they do not make regression testing with
105   the default suite more difficult. E.g.:
106
107    // register in the unnamed registry so that these tests are run by default
108    //CPPUNIT_TEST_SUITE_REGISTRATION(wxRegExTestCase);
109    CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(wxRegExTestCase, "fixme");
110
111    // also include in it's own registry so that these tests can be run alone
112    CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(wxRegExTestCase, "wxRegExTestCase");
113
1144. Tests which take a long time to execute can be registered under "advanced"
115   instead of the unnamed registry. The default suite should execute reasonably
116   quickly. To run the default and advanced tests together:
117    test "" advanced
118
119
120=== EOF ===
121
122Author:  VZ & MW
123Version: $Id: tn0017.txt 33984 2005-05-08 16:16:34Z MW $
124