Ensure Repeatable Results by Preserving Insert Order in Unique Array Generation Methods #4586
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Context:
The methods
ArrayOfUniqueValuesandArrayOfUniqueStringsaim to generate repeatable sequences of unique values or strings. The repeatability is achieved using a fixedSeed(as noted in the comment on line 16). However, the current implementation relies on the traversal order ofHashSet, which does not guarantee a consistent order.Issue:
The assumption that a fixed insertion sequence into a
HashSetensures a repeatable traversal order is flawed:HashSetdoes not provide any guarantees about order semantics in its documentation..NET, may introduce variations inSetbehavior where traversal order is inconsistent even with a fixed insertion sequence.This discrepancy could lead to non-repeatable results, breaking the method's intended behavior.
Solution:
HashSet.CopyTofor transferring elements to the result array, we now directly assign values to the array in the order they are added to theHashSet. This ensures the output matches the insertion order and remains repeatable with a fixed seed.ArrayOfUniqueValuesandArrayOfUniqueStringsmethods to reflect this approach.Changes:
ArrayOfUniqueValues:HashSet.CopyTo.ArrayOfUniqueStrings:HashSet.Benefits:
HashSettraversal.