Cause-effect graph example

De Software testing
Ir para: navegação, pesquisa

The "Print message" is a software that read two characters and, depending of their values, messages must be printed.

  • The first character must be an "A" or a "B".
  • The second character must be a digit.
  • If the first character is an "A" or "B" and the second character is a digit, the file must be updated.
  • If the first character is incorrect (not an "A" or "B"), the message X must be printed.
  • If the second character is incorrect (not a digit), the message Y must be printed.

Causes:

  • 1 - first character is "A"
  • 2 - first character is "B"
  • 3 - second character is a digit

Effects:

  • 70 - the file is updated
  • 71 - message X is print
  • 72 - message Y is print

Cause-effect graph example.png

In order to check if the graph is correct, the causes must be assigned the values 0 or 1, and the effects must be checked if they take the correct value. For those values combinations that are not possible, the graph must be annotated with constraints.

Cause-effect graph example (with constraints).png

Afterwards, the graph must be converted to a decision table.

Nodes Test case Test case Test case Test case Test case
Cause 1 0 0 1 0 1
Cause 2 0 0 0 1 0
Cause 3 0 1 1 1 0
Effect 70 0 0 1 1 0
Effect 71 1 1 0 0 0
Effect 72 1 0 0 0 1