@testset "Label propagation" begin
    n = 10
    g10 = CompleteGraph(n)
    for g in testgraphs(g10)
        z = copy(g)
        for k = 2:5
            z = blockdiag(z, g)
            add_edge!(z, (k - 1) * n, k * n)
            c, ch = @inferred(label_propagation(z))
            a = collect(n:n:(k * n))
            a = Int[div(i - 1, n) + 1 for i = 1:(k * n)]
          # check the number of communities
            @test length(unique(a)) == length(unique(c))
          # check the partition
            @test a == c
        end
    end
end
