test_plot_nethist.R
In nethist: Network Histograms

# Tests for plot.nethist() and plot.multinethist()

set.seed(42)
G      <- igraph::sample_gnp(100, p = 0.1)
hist_G <- nethist(G, h = 10)
k      <- max(hist_G$cluster)

## plot.nethist ----
test_that("plot.nethist with default arguments", {
  expect_no_error(plot(hist_G))
})

test_that("plot.nethist with type = 'prob'", {
  expect_no_error(plot(hist_G, type = "prob"))
})

test_that("plot.nethist with type = 'pmat' (alias for prob)", {
  expect_no_error(plot(hist_G, type = "pmat"))
})

test_that("plot.nethist with prob = TRUE overlays values", {
  expect_no_error(plot(hist_G, type = "prob", prob = TRUE))
})

test_that("plot.nethist with valid idx_order", {
  idx <- unique(hist_G$cluster)
  expect_no_error(plot(hist_G, idx_order = idx))
})

test_that("plot.nethist with invalid idx_order produces warning then plots", {
  expect_warning(plot(hist_G, idx_order = seq_len(k + 1)))
})

test_that("plot.nethist with invalid type errors", {
  expect_error(plot(hist_G, type = "invalid"))
})

test_that("plot.nethist with custom at scale runs without error", {
  expect_no_error(plot(hist_G, at = seq(0, 1, length.out = 20)))
})

## plot.multinethist ----
set.seed(42)
data(kite, package = "igraphdata")
kite_mat <- igraph::as_adjacency_matrix(igraph::upgrade_graph(kite), sparse = FALSE)
kite_arr <- array(kite_mat, dim = c(10, 10, 1))
mnhist   <- multinethist(kite_arr, h = 5, control = nethist_control(max_itr = 1000))

test_that("plot.multinethist with default arguments", {
  expect_no_error(plot(mnhist))
})

test_that("plot.multinethist with explicit idx_order", {
  idx <- unique(mnhist$cluster)
  expect_no_error(plot(mnhist, idx_order = idx))
})

test_that("plot.multinethist with invalid idx_order warns", {
  k_mn <- max(mnhist$cluster)
  expect_warning(plot(mnhist, idx_order = seq_len(k_mn + 1)))
})

## plot.multinethist layout validation ----
set.seed(7)
A3 <- array(0L, c(30, 30, 3))
for (l in seq_len(3)) {
  tmp <- matrix(rbinom(30 * 30, 1, 0.2), 30, 30)
  tmp <- tmp + t(tmp); diag(tmp) <- 0L
  A3[, , l] <- (tmp > 0L) * 1L
}
mnhist_multi <- multinethist(A3, h = 5, control = nethist_control(max_itr = 500))

test_that("layout: wrong length errors", {
  expect_error(plot(mnhist_multi, layout = c(3)),
               regexp = "length-2")
  expect_error(plot(mnhist_multi, layout = c(3, 4, 5)),
               regexp = "length-2")
})

test_that("layout: non-positive or NA values error", {
  expect_error(plot(mnhist_multi, layout = c(0, 4)),
               regexp = "length-2")
  expect_error(plot(mnhist_multi, layout = c(-1, 4)),
               regexp = "length-2")
  expect_error(plot(mnhist_multi, layout = c(NA, 4)),
               regexp = "length-2")
})

test_that("layout: non-numeric errors", {
  expect_error(plot(mnhist_multi, layout = "3x4"),
               regexp = "length-2")
})

test_that("layout: grid too small for number of layers errors", {
  expect_error(plot(mnhist_multi, layout = c(1, 1)),
               regexp = "cells")
})

test_that("layout: valid grid runs without error", {
  expect_no_error(plot(mnhist_multi, layout = c(2, 2)))
})

test_that("layout: NULL default runs without error", {
  expect_no_error(plot(mnhist_multi))
})

test_that("plot.multinethist single-layer with custom at runs without error", {
  expect_no_error(plot(mnhist, at = seq(0, 1, length.out = 20)))
})

test_that("plot.multinethist multilayer with custom at runs without error", {
  expect_no_error(plot(mnhist_multi, at = seq(0, 1, length.out = 20)))
})