Fix tests

test/Project.toml

@@ -2,6 +2,8 @@
 Dictionaries = "85a47980-9c8c-11e8-2b9f-f7ca1fa99fb4"
 Graphs = "86223c79-3864-5bf0-83f7-82e725a168b6"
 GraphsFlows = "06909019-6f44-4949-96fc-b9d9aaa02889"
+KaHyPar = "2a6221f6-aa48-11e9-3542-2d9e0ef01880"
+Metis = "2679e427-3c69-5b7f-982b-ece356f1e94b"
 NamedGraphs = "678767b0-92e7-4007-89e4-4527a8725b19"
 Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"

test/test_partitionedgraph.jl

@@ -12,6 +12,7 @@ using Graphs:
   random_regular_graph,
   rem_vertex!,
   vertices
+using Metis: Metis
 using NamedGraphs: NamedEdge, NamedGraph
 # TODO: Move to `NamedGraphGenerators`.
 using NamedGraphs: named_comb_tree, named_grid, named_triangular_lattice_graph
@@ -39,6 +40,7 @@ using NamedGraphs.PartitionedGraphs:
   partitionvertices,
   unpartitioned_graph
 using Dictionaries: Dictionary, dictionary
+using Pkg: Pkg
 using Test: @test, @testset
 
 @testset "Test Partitioned Graph Constructors" begin
@@ -174,14 +176,13 @@ end
 end
 
 @testset "Test NamedGraphs Functions on Partitioned Graph" begin
-  functions = [is_tree, default_root_vertex, center, diameter, radius]
-  gs = [
+  functions = (is_tree, default_root_vertex, center, diameter, radius)
+  gs = (
     named_comb_tree((4, 4)),
     named_grid((2, 2, 2)),
     NamedGraph(random_regular_graph(12, 3)),
     named_triangular_lattice_graph(7, 7),
-  ]
-
+  )
   for f in functions
     for g in gs
       pg = PartitionedGraph(g, [vertices(g)])
@@ -193,4 +194,20 @@ end
     end
   end
 end
+
+@testset "Graph partitioning" begin
+  g = named_grid((4, 4))
+  npartitions = 4
+  backends = ["metis"]
+  if !Sys.iswindows()
+    # `KaHyPar` doesn't work on Windows.
+    Pkg.add("KaHyPar"; io=devnull)
+    push!(backends, "kahypar")
+  end
+  for backend in backends
+    pg = PartitionedGraph(g; npartitions, backend="metis")
+    @test pg isa PartitionedGraph
+    @test nv(partitioned_graph(pg)) == npartitions
+  end
+end
 end