Sort roles by position in permissions calculation #609
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The crux of this bug is based on the fact that the internal order of
roles is undefined: they are in whatever order Discord sends them to us.
This causes our reduce to be unstable based on this position, because of
the following, where:
- each element is a role
- "true" represents permissions field being checked
- pN is the roles position
[false, true, false].reduce { |a, e| e } # => false
p1 p3^^ p2
[false, false, true].reduce { |a, e| e } # => true
p1 p2 p3^^
Sorting during our reduction ensures a set permission by a higher role
is not masked by a lower one.
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The crux of this bug is based on the fact that the internal order of roles is undefined: they are in whatever order Discord sends them to us. This causes our reduce to be unstable based on this position, because of the following, where:
truerepresents permissions field being checkedpNis the roles positionSorting during our reduction ensures a set permission by a higher role
is not masked by a lower one.
Fixes #607