SNOW-1434962: Make groupby.apply sort result deterministic. #1625
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Fixes SNOW-1434962
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sort_values
by default is not stable since it useskind="quicksort"
. Use a stablenlargest
call with the default ofkeep="first"
so that when multiple rows have the same price, we get them in the order that they appear in the input dataframe.Unfortunately I couldn't reproduce the flake locally by running the test repeatedly unless I manually changed the order of the input dataframe before the
sort_values
to simulate instability ofsort_values
. However, I think now we should be able to count on the stability ofnlargest
.