--- a
+++ b/tests/testthat/test-graph.R
@@ -0,0 +1,34 @@
+test_that("spatial graphs", {
+  
+  # get data
+  data("xenium_data")
+  
+  # spatial graphs
+  xenium_data <- getSpatialNeighbors(xenium_data, method = "delaunay", verbose = FALSE)
+  graphs <- vrGraph(xenium_data, graph.type = "delaunay")
+  expect_true(inherits(graphs,"igraph"))
+  expect_true(length(igraph::E(graphs)) > 0)
+})
+
+test_that("overwrite graphs", {
+  
+  # spatial graphs
+  data("xenium_data")
+  xenium_data <- getSpatialNeighbors(xenium_data, method = "delaunay", verbose = FALSE)
+  graphs <- vrGraph(xenium_data, graph.type = "delaunay")
+  xenium_data <- getSpatialNeighbors(xenium_data, method = "delaunay", verbose = FALSE)
+  graphs <- vrGraph(xenium_data, graph.type = "delaunay")
+  expect_true(inherits(graphs,"igraph"))
+  expect_true(length(igraph::E(graphs)) > 0)
+  
+  # overwrite using subset of metadata groups
+  data("xenium_data")
+  xenium_data <- getSpatialNeighbors(xenium_data, method = "delaunay", group.by = "clusters", group.ids = c(1,2,3,4), verbose = FALSE)
+  graphs <- vrGraph(xenium_data, graph.type = "delaunay")
+  expect_true(inherits(graphs,"igraph"))
+  expect_true(length(igraph::E(graphs)) > 0)
+  xenium_data <- getSpatialNeighbors(xenium_data, method = "delaunay", group.by = "clusters", group.ids = c(3,4,5,6), verbose = FALSE)
+  graphs <- vrGraph(xenium_data, graph.type = "delaunay")
+  expect_true(inherits(graphs,"igraph"))
+  expect_true(length(igraph::E(graphs)) > 0)
+})
\ No newline at end of file