test: put all tests of interface.R in a single test file

tests/testthat/test-interface.R

@@ -0,0 +1,119 @@
+test_that("add_edges keeps edge id order", {
+  g <- make_empty_graph(10)
+  edges <- c(1, 2, 2, 3, 3, 4, 1, 6, 1, 7, 9, 10)
+  g2 <- add_edges(g, edges)
+
+  expect_equal(ecount(g2), length(edges) / 2)
+  expect_equal(get.edge.ids(g2, edges), seq_len(length(edges) / 2))
+})
+
+test_that("add_edges adds attributes", {
+  g <- make_empty_graph(10)
+  edges <- c(1, 5, 2, 6, 3, 10, 4, 5)
+  weights <- c(1, 2, 1, -1)
+  g3 <- add_edges(g, edges, attr = list(weight = weights))
+
+  expect_equal(ecount(g3), (length(edges) / 2))
+  expect_equal(get.edge.ids(g3, edges), seq_len(length(edges) / 2))
+  expect_equal(E(g3)$weight, weights)
+})
+
+test_that("add_edges unknown attributes to NA", {
+  g <- make_empty_graph(10)
+  edges <- c(1, 2, 2, 3, 3, 4, 1, 6, 1, 7, 9, 10)
+  g2 <- add_edges(g, edges)
+  g4 <- add_edges(g2, c(1, 4, 4, 6, 7, 1), attr = list(weight = c(-1, 1, -2.5)))
+
+  expect_true(all(is.na(E(g4)$weight[seq_len(length(edges) / 2)])))
+})
+
+test_that("add_edges appends attributes properly", {
+  g <- make_empty_graph(10)
+  edges1 <- c(1, 5, 2, 6, 3, 10, 4, 5)
+  weights1 <- c(1, 2, 1, -1)
+  g2 <- add_edges(g, edges1, attr = list(weight = weights1))
+
+  edges2 <- c(10, 9, 10, 10, 1, 1)
+  weights2 <- c(100, 100, 100)
+  g3 <- add_edges(g2, edges2, attr = list(weight = weights2))
+  expect_equal(E(g3)$weight, c(weights1, weights2))
+})
+
+test_that("add_edges signals error for zero vertex ids", {
+  g <- make_full_graph(5) %du% make_full_graph(5) %du% make_full_graph(5)
+  expect_error(add_edges(g, c(0, 5, 0, 10, 5, 10)), "Invalid vertex")
+})
+
+test_that("add_vertices works", {
+  g <- graph_from_literal(A - B - C - D - E)
+  nv <- 4
+  g2 <- add_vertices(g, nv = nv)
+
+  expect_equal(vcount(g2), vcount(g) + nv)
+  expect_equal(ecount(g2), ecount(g))
+  expect_equal(as_edgelist(g2), as_edgelist(g))
+})
+
+test_that("add_vertices handles attributes properly", {
+  g <- graph_from_literal(A - B - C - D - E)
+  nv <- 3
+  names <- c("F", "G", "H")
+  weights <- 1:3
+  g3 <- add_vertices(g, nv = nv, attr = list(name = names, weight = weights))
+
+  expect_equal(V(g3)$name, c(V(g)$name, names))
+  expect_equal(V(g3)$weight, c(rep(NA, vcount(g)), weights))
+})
+
+test_that("delete_vertices works", {
+  g <- graph_from_literal(A:B:C - D:E:F, D - E - F)
+
+  g2 <- delete_vertices(g, "A")
+  expect_equal(V(g2)$name, c("B", "C", "D", "E", "F"))
+
+  g3 <- delete_vertices(g, match("A", V(g)$name))
+  expect_isomorphic(g2, g3)
+})
+
+test_that("neighbors works", {
+  g <- sample_gnp(100, 20 / 100)
+  al <- as_adj_list(g, mode = "all")
+  for (i in seq_along(al)) {
+    n <- neighbors(g, v = i, mode = "out")
+    expect_setequal(sort(n), al[[i]])
+  }
+})
+
+test_that("neighbors prints an error for an empty input vector", {
+  g <- make_tree(10)
+  expect_error(neighbors(g, numeric()), "No vertex was specified")
+})
+
+
+test_that("delete_edges works", {
+  g <- graph_from_literal(A:B:C - D:E:F, D - E - F)
+  g2 <- delete_edges(g, E(g, P = c("D", "E")))
+
+  expected_matrix <- matrix(
+      c(
+        0, 0, 0, 1, 1, 1,
+        0, 0, 0, 1, 1, 1,
+        0, 0, 0, 1, 1, 1,
+        1, 1, 1, 0, 0, 0,
+        1, 1, 1, 0, 0, 1,
+        1, 1, 1, 0, 1, 0
+      ),
+      nrow = 6L,
+      ncol = 6L,
+      dimnames = list(c("A", "B", "C", "D", "E", "F"), c("A", "B", "C", "D", "E", "F"))
+    )
+
+  expect_equal(as.matrix(g2[]), expected_matrix)
+})
+
+test_that("ends works", {
+  g <- sample_gnp(100, 3 / 100)
+  edges <- unlist(lapply(seq_len(ecount(g)), ends, graph = g))
+  g2 <- make_graph(edges, dir = FALSE, n = vcount(g))
+  expect_isomorphic(g, g2)
+})