DisjointSets with Any type never stops

[DanielVandH]

The following code seems to never stop:

julia> using DataStructures

julia> DisjointSets{Any}() # good
DisjointSets{Any}(Dict{Any, Int64}(), Any[], IntDisjointSets{Int64}(Int64[], Int64[], 0))

julia> DisjointSets{Any}([])
ERROR: InterruptException:
Stacktrace:
 [1] DisjointSets{Any}(xs::Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Vector{Any}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}) (repeats 204 times)
   @ DataStructures C:\Users\licer\.julia\packages\DataStructures\59MD0\src\disjoint_set.jl:165
 [2] top-level scope
   @ REPL[368]:1

The Any type seems to be the issue, since e.g.

julia> DisjointSets{Float64}([])
DisjointSets{Float64}(Dict{Float64, Int64}(), Float64[], IntDisjointSets{Int64}(Int64[], Int64[], 0))

Note that [] is just to have an element. It also fails for non-empty sets:

julia> DisjointSets{Any}([1,2,3])
ERROR: InterruptException:
Stacktrace:
 [1] DisjointSets{Any}(xs::Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Tuple{Vector{Int64}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}) (repeats 140 times)
   @ DataStructures C:\Users\licer\.julia\packages\DataStructures\59MD0\src\disjoint_set.jl:165
 [2] top-level scope
   @ REPL[370]:1

works.

[willow-ahrens]

I think this is related to #755