Best Practice fix: The expression $associations of type array is implicitly converted to a boolean; using !empty($expr) instead to make it clear that we intend to check for an array without elements.
Imho, the only difference between !empty() and the 'boolean' check is that empty also has an issetcheck included. Other than that they work exactly the same as far as I am aware.
So it just boils down to personal flavor which you want to use.
Personally I prefer the boolean check as I don't like the "double negation" of !empty. I only use empty when I'm not sure if the variable is defined or not. Then I can avoid using an additional isset check. But that's me, others handle it different.
zero-24
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@test OK by code review: I agree!!