This lesson explains how to use the Forced Interactions feature of DesignWise. If you want your tests to include specific combinations of Values, this one is for you!
When to Use Forced Interactions
Do you need DesignWise tests to include a particular test for a required business rule? For example…
Requirement: (#2947 – Notify about Certain High Risk Flood Zone Applications)
The business rule that you want to test reads, “if a regular applicant applies for a large loan in a flood zone with 90% LTV, send the notification to the manager.”
Ask yourself: “How many test inputs do I need to trigger this business rule?”
To test this business rule, you must have these specific 4 Values included together in a single script:
- Customer status must be Regular
- Loan to value ratio must be 90%
- Loan amount must be Large
- And the property needs to be In a Flood Zone
(At the risk of stating the obvious, if this analysis shows that your model does not yet include all of the specific Values needed to test the business rule, you may need to go back to the “Parameters” screen and add one or more Parameter and/or Value)
Go to the Forced Interactions screen under Rules and add your scenario. It’s simple.
How to Use Forced Interactions
Both of these steps are optional:
- Type the name and/or number of your forced scenario
- Type its expected result.
That’s it! When you create your tests, your forced scenario will appear in a newly-generated set of tests!
Keep the following usage tips in mind when using Forced Interactions:
- This feature is not just for “official requirements.” Consider including other critical ideas in your DesignWise-generated suite, like a forced scenario that contains the most common Value for each Parameter (i.e. “Happy Path”).
- As shown above, you don’t need to specify every Value. In fact, it’s better if you only force the Values needed to trigger the requirement/business rule. That way, the most variation is possible in your DesignWise-generated tests.
- Keep the concept of “Expected Results” clearly separated in your mind from ordinary Parameters and Values. Typically, do not enter Expected Result values in the “Parameters” screen. The primary places you should enter the Expected Result are the “Forced Interactions” and “Scripts” screens. You can read more in the “How to Handle Expected Results” article from the Test Design Principles section.
- Use this feature selectively. Remember that many combinations will automatically appear in your DesignWise-generated scenarios without you needing to do anything special. If you have a business rule that only requires two Values to appear together, for example, that requirement will already be satisfied automatically whenever you create a 2-way (“pairwise”) set of tests. If you’re creating a 2-way set of tests, you would only need to use this special feature when you’re trying to ensure that 3 or more specific Values get tested together in a single test case.