Don't use length() as it's expensive #1021
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Replace expensive length/1 calls with more performant alternatives to fix Credo warnings flagged in CI[1]. - In scheduler.ex: Use pattern matching [_ | _] instead of length(events) > 0 in guard clause - In test files: Replace assert length(stack) > 0 with refute Enum.empty?(stack) for clearer intent and better performance In Elixir, length/1 is O(n) because lists are implemented as linked lists, requiring traversal of the entire list to count elements. For emptiness checks, pattern matching against [] or [_ | _] is O(1) and Enum.empty?/1 stops at the first element, making them much more efficient than counting all elements just to compare with zero. These changes maintain the same functionality while following Elixir best practices for checking list emptiness. [1]: https://github.com/appsignal/appsignal-elixir/actions/runs/19948488321/job/57203328408 [skip changeset]
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Replace expensive
length/1calls with more performant alternatives to fix Credo warnings flagged in CI1.[_ | _]instead oflength(events) > 0in guard clauseassert length(stack) > 0withrefute Enum.empty?(stack)for clearer intent and better performanceIn Elixir,
length/1is O(n) because lists are implemented as linked lists, requiring traversal of the entire list to count elements. For emptiness checks, pattern matching against[]or[_ | _]is O(1) andEnum.empty?/1stops at the first element, making them much more efficient than counting all elements just to compare with zero.
These changes maintain the same functionality while following Elixir best practices for checking list emptiness.