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defect in an ordinary algorithm comparison table

Subject	have testing strategy	cause by	catch using	has definition	be	hide until
incorrect logical conditions	using equivalence class and boundary testing - to compute the equivalence classes, consider as an input each variable used in a rule or logical condition			A common defect in which the logical conditions that govern looping and if-then-else statements are wrongly formulated
not handling null conditions	determine all possible null conditions and run test cases that would highlight any inappropriate behaviour			A common defect in which a program behaves abnormally when a null condition is encountered
not handling singleton or non-singleton conditions	brainstorm to determine unusual conditions and run appropriate tests			A common defect in which a program does not properly handle singleton conditions or non-singleton conditions
not setting up the correct preconditions for an algorithm	run test cases in which each precondition is not satisfied - preferably its input values are just beyond what the algorithm can accept			A common defect in which a program proceeds to do its work even when specifies preconditions, that state what must be true before the algorithm should be executed, are not satisfied
not terminating a loop or recursion	assume that the programmer has made an error should analyse what causes a repetitive action to be stopped should run test cases that the tester anticipates might not be handled correctly			A common defect in which a loop or a recursion does not always terminate, i.e. it is 'infinite'
off-by-one error	develop boundary tests in which you verify that the program computes the correct numerical answer, or performs the correct number of iterations			A defect in which a program inappropriately adds or subtracts one, or inappropriately loops one too many times or one too few times	very common especially in graphical applications
operator precedence error	run tests that anticipate possible errors use code inspections			A defect in which a programmer omits needed parentheses, or puts parentheses in the wrong place	obvious	special conditions arise
performing a calculation in the wrong part of a control construct	design tests that execute each loop zero times, exactly once, and more than once ensure that anything 'bad' or 'unusual' that could happen while looping is made to occur on the first iteration and the last iteration	inappropriately excluding the action from, or including the action in, a loop or if-then-else construct	black-box testing, so glass-box testing or inspections may be more effective	A common defect in which the program performs an action when it should not, or does not perform an action when it should
use of an inappropriate standard algorithm	design tests that highlight the properties of inappropriate algorithms such as execution time			A common defect in which an unnecessarily inefficient or otherwise inappropriate algorithm is used

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