Added test to previous fix

Author: fverdugo

test/mpi_array/drivers/mpi_array_tests.jl

@@ -1,12 +1,26 @@
 module MPIArrayTests
 
 using PartitionedArrays
+using Test
 
 with_mpi() do distribute
     rank = distribute(LinearIndices((4,)))
     display(rank)
     rank = distribute(LinearIndices((2,2)))
     display(rank)
+
+    n = 4
+    row_partition = uniform_partition(rank,n)
+    my_own_to_global = map(own_to_global,row_partition)
+    ids = gather(my_own_to_global)
+    map_main(ids) do myids
+        @test myids == [[1],[2],[3],[4]]
+    end
+    ids = gather(my_own_to_global,destination=:all)
+    map(ids) do myids
+        @test myids == [[1],[2],[3],[4]]
+    end
+
 end
 
 end # module