tests/testthat/test-bipartite_edge_swap2.R

In jhrcook/wext: Weighted Exclusivity Test (WExT)

test_that("the edge list is made correctly for a bipartite graph", {
    library(tidygraph)
    library(dplyr)
    library(tibble)

    empty_gr <- create_empty(n = 10) %N>%
        mutate(type = rep(c(TRUE, FALSE), 5),
               name = LETTERS[1:10])
    expect_error(to_bipartite_edgelist(empty_gr), regexp = "no edges")

    ring_gr <- create_ring(n = 20) %N>%
        mutate(type = rep(c(TRUE, FALSE), 10),
               name = LETTERS[1:20])
    ring_el <- to_bipartite_edgelist(ring_gr)
    expect_equal(length(ring_el), 2)
    expect_equal(length(ring_el$nodes1), igraph::ecount(ring_gr))
    expect_equal(length(ring_el$nodes2), igraph::ecount(ring_gr))
    expect_true(
        length(intersect(unlist(ring_el$nodes1), unlist(ring_el$nodes2))) == 0
    )
})

test_that("an edge list is converted back to a bipartite graph correctly", {
    library(tidygraph)
    library(dplyr)
    library(tibble)

    el <- list(c(1,3,5,7), c(2,4,6,8))
    gr <- edgelist_to_bipartite_graph(el)
    expect_true(is.tbl_graph(gr))
    expect_equal(igraph::ecount(gr), 4)
    expect_equal(igraph::vcount(gr), 8)
    expect_true(check_gr(gr, "name"))
    expect_true(check_gr(gr, "type"))


    el <- list(c("A", "A", "A", "B", "B"),
               c("E", "C", "D", "C", "D"))
    gr <- edgelist_to_bipartite_graph(el, 1)
    expect_equal(igraph::vcount(gr), 5)
    expect_equal(igraph::ecount(gr), 5)
    expect_true(check_gr(gr, "name"))
    expect_true(check_gr(gr, "type"))
    v1 <- gr %N>% filter(type) %>% as_tibble() %>% pull(name) %>% unlist()
    v2 <- gr %N>% filter(!type) %>% as_tibble() %>% pull(name) %>% unlist()
    expect_true(all(v1 %in% unlist(el[1])))
    expect_true(all(v2 %in% unlist(el[2])))

    gr <- edgelist_to_bipartite_graph(el, 2)
    v1 <- gr %N>% filter(type) %>% as_tibble() %>% pull(name) %>% unlist()
    v2 <- gr %N>% filter(!type) %>% as_tibble() %>% pull(name) %>% unlist()
    expect_true(all(v1 %in% unlist(el[2])))
    expect_true(all(v2 %in% unlist(el[1])))
})


test_that("properly swap edges of a bipartite graph (method 2)", {
    library(igraph)
    library(tidygraph)

    for (i in 1:50) {
        gr <- as_tbl_graph(simple_dataset, directed = FALSE)
        expect_error(bipartite_edge_swap2(gr, Q = 100), regexp = "not a node attribute")
        gr <- gr %N>%
            mutate(type = name %in% unlist(simple_dataset$sample_name))

        swapped_gr <- bipartite_edge_swap2(gr, Q = 100)

        expect_true(vcount(gr) == vcount(swapped_gr))
        expect_true(ecount(gr) == ecount(swapped_gr))
        expect_true(igraph::is_simple(swapped_gr))

        el <- as_edgelist(swapped_gr, names = TRUE)

        # {boolean} is x a digit
        is_digit <- function(x) stringr::str_detect(x, "[:digit:]")
        # {boolean} is x a letter
        is_letter <- function(x) stringr::str_detect(x, "[:alpha:]")

        check_edge <- function(nodes) {
            if (is_digit(nodes[[1]]) & is_letter(nodes[[2]])) {
                return(TRUE)
            } else if (is_digit(nodes[[2]]) & is_letter(nodes[[1]])) {
                return(TRUE)
            } else {
                return(FALSE)
            }
        }

        checks <- apply(el, 1, check_edge)
        expect_true(all(checks))
    }
})