Data Flow Testing - Strategies

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From the figure, we see that variables A and B are defined on link (1,2). It is evident that any path taken for the graph will traverse through (1,2) . Hence the criterion for variables A & B as per ADUP is satisfied. But we have a redefinition at link (3,4). Variable C will not satisfy ADUP if only the path (1,3) is taken, thus violating the ADUP definition. ADUP becomes complicated when a variable is redefined in many places.

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  àhis shows the relative strength of data flow & control flow testing strategies. 

  àest cases are based on the elative strength of 

 testing strategies.









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 àhe strength of the testing strategies reduces along the Direction of the arrow. For example, All-Uses is weaker than All DU paths.

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