False negative on "unused return values" ?

[kbaird]

Hi. The code at photomattmills/ecto_neo4j#4 reports a warning:

┃ [W] ↗ There should be no unused return values for Enum.map().
┃       lib/ecto_neo4j.ex:61:15 (Ecto.Neo4j.sort_column)

That I believe is incorrect. The context is a value returned from an if check being the last evaluated expression in a function:

    if hd(cols) do
      coercer = fn({name, type}) -> coerce(type, col[Atom.to_string(name)]) end 
      cols |> Enum.map(coercer)
    else
      [nil]
    end

It looks like the presence of the [nil] and end lines below the Enum.map/2 is confusing it into thinking that there are additional expressions leading the map value to be discarded.

[rrrene]

Thanks for reporting this, it indeed looks like a bug! 👍

I will look into it!

[rrrene]

Bugfix is live in v0.2.6 - Thanks again Kevin for a comprehensive bug report. Open Source at its best! 👍

[kbaird]

Thanks for such a quick fix.