tests/testthat/test-surface_points_template.R

In BoneDensityMapping: Maps Bone Densities from CT Scans to Surface Models

url <- "https://github.com/Telfer/BoneDensityMapping/releases/download/v1.0.2/test_CT_femur.stl"
bone_filepath <- tempfile(fileext = ".stl")
download.file(url, bone_filepath, mode = "wb")
surface_mesh <- import_mesh(bone_filepath)

url2 <- "https://github.com/Telfer/BoneDensityMapping/releases/download/v1.0.1/test_CT_hip.nii.gz"
scan_filepath <- tempfile(fileext = ".nii.gz")
download.file(url2, scan_filepath, mode = "wb")
nifti <- import_scan(scan_filepath)

landmark_path <- system.file("extdata", "test_femur.mrk.json", package = "BoneDensityMapping")
landmarks <- import_lmks(landmark_path)

test_that("surface_points_template returns a data.frame with correct dimensions", {
  n_sliders <- 100
  result <- surface_points_template(surface_mesh, landmarks, n_sliders)

  expect_s3_class(result, "data.frame")
  # Number of rows = number of original landmarks + number of sliders
  expect_equal(nrow(result), nrow(landmarks) + n_sliders)
  # Expect 3 columns (xpts, ypts, zpts)
  expect_equal(ncol(result), 3)
  # Columns should be numeric
  expect_true(all(sapply(result, is.numeric)))
})

test_that("surface_points_template errors when surface mesh is missing vertices", {
  # Create dummy invalid mesh object
  bad_mesh <- list(vb = matrix(numeric(0), nrow=4, ncol=0))

  landmark_path <- system.file("extdata", "test_femur.mrk.json", package = "BoneDensityMapping")
  landmarks <- import_lmks(landmark_path)

  expect_error(surface_points_template(bad_mesh, landmarks, 10))
})