CSE306 Software Quality in Practice - University at Buffalo · CSE306 Software Quality in Practice...

CSE306 Software Quality in Practice

Dr. Carl Alphonce alphonce@buffalo.edu

343 Davis Hall

Recall the rules1. Understand the requirements 2. Make it fail 3. Simplify the test case 4. Read the right error message 5. Check the plug 6. Separate fact from fiction 7. Divide and conquer 8. Match the tool to the bug 9. One change at a time 10. Keep an audit trail 11. Get a fresh view 12. If you didn’t fix it, it ain’t fixed 13. Cover your bug fix with a regression test

Recall the rules1. Understand the requirements 2. Make it fail 3. Simplify the test case 4. Read the right error message 5. Check the plug 6. Separate fact from fiction 7. Divide and conquer 8. Match the tool to the bug 9. One change at a time 10. Keep an audit trail 11. Get a fresh view 12. If you didn’t fix it, it ain’t fixed 13. Cover your bug fix with a regression test

Recall the rules1. Understand the requirements 2. Make it fail 3. Simplify the test case 4. Read the right error message 5. Check the plug 6. Separate fact from fiction 7. Divide and conquer 8. Match the tool to the bug 9. One change at a time 10. Keep an audit trail 11. Get a fresh view 12. If you didn’t fix it, it ain’t fixed 13. Cover your bug fix with a regression test

Unit testing frameworks

uniform way of expressing tests

manage tests through suites

automate testing process

Remember JUnit?

We'll use CUnit

http://cunit.sourceforge.net

http://cunit.sourceforge.net/doc

http://cunit.sourceforge.net/doc/introduction.html

http://cunit.sourceforge.net/doc/introduction.html

a test

a void -> void method

test methods must be part of a test suite, which must in turn be registered with registry, before it will be run

Assertions (the most common ones)

CU_ASSERT_TRUE(x) CU_ASSERT_EQUAL(x,y) CU_ASSERT_PTR_EQUAL(x,y) CU_ASSERT_PTR_NULL(x,y) CU_ASSERT_STRING_EQUAL(x,y) CU_ASSERT_DOUBLE_EQUAL(x,y,𝜀) CU_PASS(message)

CU_ASSERT_FALSE(x) CU_ASSERT_NOT_EQUAL(x,y) CU_ASSERT_PTR_NOT_EQUAL(x,y) CU_ASSERT_PTR_NOT_NULL(x,y) CU_ASSERT_STRING_NOT_EQUAL(x,y) CU_ASSERT_DOUBLE_NOT_EQUAL(x,y,𝜀) CU_FAIL(message)

http://cunit.sourceforge.net/doc/headers/CUnit.h

LIVE EXAMPLE

Live coding reconstruction

Production code

Test code

Test code is separate from production code, but calls production code to verify its functionality.

Live coding reconstruction

void test00(void) { int x = 5; int y = -3; int expected = 2; int actual = eval(x, y); CU_ASSERT_EQUAL( expected , actual ); }

A test is a void to void function. Set up inputs and an expected (correct) answer. Compute an actual answer using production code. Compare actual and expected values.

Live coding reconstruction

void test01(void) { runTest(1,1,2); } void test02(void) { runTest(2,1,3); } void test03(void) { runTest(0,2,2); } void test04(void) { runTest(2,0,2); }

/* Runs a test with inputs that *should* pass * and produce an expected result. */ void runTest(int x, int y, int expected) { int actual = eval(x, y); CU_ASSERT_EQUAL( expected , actual ); }

Can simplify writing many tests by using a helper function, runTest.

Live coding reconstruction

Needed #includes:

#include "CUnit.h" #include "Basic.h"

Live coding reconstruction

/* The main() function for setting up and running the tests. */ int main() { CU_pSuite SuiteValid = NULL; /* initialize the CUnit test registry */ if (CUE_SUCCESS != CU_initialize_registry()) { return CU_get_error(); } /* add a suite to the registry */ SuiteValid = CU_add_suite("Suite_of_tests_with_valid_inputs", NULL, NULL); if (NULL == SuiteValid) { CU_cleanup_registry(); return CU_get_error(); } /* add the tests to SuiteValid */ if ( (NULL == CU_add_test(SuiteValid, "5+(-3)=2", test00)) || (NULL == CU_add_test(SuiteValid, "1+1=2", test01)) ) { CU_cleanup_registry(); return CU_get_error(); }

/* Run all tests using the CUnit Basic interface */ CU_basic_set_mode(CU_BRM_VERBOSE); CU_basic_run_tests();

CU_cleanup_registry(); return CU_get_error(); }

Live coding reconstruction

/* The main() function for setting up and running the tests. */ int main() { CU_pSuite SuiteValid = NULL; /* initialize the CUnit test registry */ if (CUE_SUCCESS != CU_initialize_registry()) { return CU_get_error(); } /* add a suite to the registry */ SuiteValid = CU_add_suite("Suite_of_tests_with_valid_inputs", NULL, NULL); if (NULL == SuiteValid) { CU_cleanup_registry(); return CU_get_error(); } /* add the tests to SuiteValid */ if ( (NULL == CU_add_test(SuiteValid, "5+(-3)=2", test00)) || (NULL == CU_add_test(SuiteValid, "1+1=2", test01)) ) { CU_cleanup_registry(); return CU_get_error(); }

/* Run all tests using the CUnit Basic interface */ CU_basic_set_mode(CU_BRM_VERBOSE); CU_basic_run_tests();

CU_cleanup_registry(); return CU_get_error(); }

Create a test suite. In this case the suite is named SuiteValid.

Live coding reconstruction

/* The main() function for setting up and running the tests. */ int main() { CU_pSuite SuiteValid = NULL; /* initialize the CUnit test registry */ if (CUE_SUCCESS != CU_initialize_registry()) { return CU_get_error(); } /* add a suite to the registry */ SuiteValid = CU_add_suite("Suite_of_tests_with_valid_inputs", NULL, NULL); if (NULL == SuiteValid) { CU_cleanup_registry(); return CU_get_error(); } /* add the tests to SuiteValid */ if ( (NULL == CU_add_test(SuiteValid, "5+(-3)=2", test00)) || (NULL == CU_add_test(SuiteValid, "1+1=2", test01)) ) { CU_cleanup_registry(); return CU_get_error(); }

/* Run all tests using the CUnit Basic interface */ CU_basic_set_mode(CU_BRM_VERBOSE); CU_basic_run_tests();

CU_cleanup_registry(); return CU_get_error(); }

Register each test function with the SuiteValid test suite here.

If you add more test functions for this suite, add code here to register each test function.

Live coding reconstruction

/* The main() function for setting up and running the tests. */ int main() { CU_pSuite SuiteValid = NULL; /* initialize the CUnit test registry */ if (CUE_SUCCESS != CU_initialize_registry()) { return CU_get_error(); } /* add a suite to the registry */ SuiteValid = CU_add_suite("Suite_of_tests_with_valid_inputs", NULL, NULL); if (NULL == SuiteValid) { CU_cleanup_registry(); return CU_get_error(); } /* add the tests to SuiteValid */ if ( (NULL == CU_add_test(SuiteValid, "5+(-3)=2", test00)) || (NULL == CU_add_test(SuiteValid, "1+1=2", test01)) || (NULL == CU_add_test(SuiteValid, "1+2=3", test02)) || (NULL == CU_add_test(SuiteValid, "0+2=2", test03)) || (NULL == CU_add_test(SuiteValid, "2+0=2", test04)) ) { CU_cleanup_registry(); return CU_get_error(); }

/* Run all tests using the CUnit Basic interface */ CU_basic_set_mode(CU_BRM_VERBOSE); }

This is what it looks like with more test functions registered.

Branching and merging in git

A sequence of commits all in the master branch.

commit 1

commit 2

commit 3 master

HEAD

Branching and merging in git

Create a new branch: git branch bugfix

commit 1

commit 2

commit 3 master

HEAD

bugfix

Branching and merging in git

Move HEAD to new branch git checkout bugfix

commit 1

commit 2

commit 3 master

HEAD

bugfix

Branching and merging in git

Make a commit on bugfix branch

commit 1

commit 2

commit 3 master

HEAD

bugfixcommit

4

Branching and merging in git

Make another commit on bugfix

branch

commit 1

commit 2

commit 3 master

HEAD

bugfixcommit

4

commit 5

Branching and merging in git

Check out master again

commit 1

commit 2

commit 3 master

HEAD

bugfixcommit

4

commit 5

Branching and merging in git

Merge bugfix into master. Since no other commits were made to master in between this

merge is straightforward.

commit 1

commit 2

commit 3 master

HEAD

bugfix

commit 4

commit 5