The following two situations are particularly interesting.
IUT is determinisitic. A typical situation is that the behavior of the IUT is known to
be deterministic. This means that if an observable action happens in a certain state,
then the same observable action will happen again when that same state is visited.
Assume that the model program is written in such a way that its states correspond
to the states of the IUT so that there are no ???hidden??? states. The model program
may still allow multiple choices, because it is not known what the particular implementation
is, only that it is deterministic. Suppose also that all states of the model
program are either passive or active.
The strategy can record in a map P for each reached passive state the observable
action that occurred in that state. Say that a state is partially explored if it is active and
there exists an unexplored controllable action that is enabled in that state. Suppose
that the goal of the strategy is to maximize transition coverage. When computing
what controllable action to select, a possible algorithm could be to select an action
that has not been explored or to select an action that takes the strategy closer to a
partially explored state. Such an algorithm should be incremental. In this calculation,
P is used to determine what transitions take place from passive states.
Suppose, for example, that the bag implementation in Figure 12.
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