test_that("the R and C++ shared-neighbor implementations agree", {
  data <- rbind(
    c(0, 0),
    c(0, 1),
    c(1, 0),
    c(1, 1),
    c(3, 3),
    c(3, 4)
  )

  invisible(capture.output(
    reference <- SharedNeighbor_Distance(
      data,
      k = 2,
      NThreads = 1,
      ComputationInR = TRUE
    )
  ))
  invisible(capture.output(
    observed <- SharedNeighbor_Distance(
      data,
      k = 2,
      NThreads = 1,
      ComputationInR = FALSE
    )
  ))

  expect_equal(observed, reference)
  expect_equal(observed, t(observed))
  expect_equal(diag(observed), rep(0, nrow(data)))
})