A shortcut function could be added to reduce duplicated code in tests

[cahirodoherty-learningpool]

Subject of the issue/enhancement/features

For every plugin we are repeating a lot of code around testContainsOrNotExists for multiple fields.

I am proposing that we create a shortcut function which accepts a full object and iterates over it to test multiple fields in one swoop. Plugins tests files will be simplified as a result