diff --git a/tests/testthat/test-utils.R b/tests/testthat/test-utils.R
index 35950b6..17aff66 100644
--- a/tests/testthat/test-utils.R
+++ b/tests/testthat/test-utils.R
@@ -1,3 +1,34 @@
 # Tests for utility functions --------------------------------------------------
 
+## Test get colours function ----
 testthat::expect_type(get_colours(pattern = "Blue"), "character")
+testthat::expect_type(get_colours(pattern = "Blue", named = TRUE), "character")
+testthat::expect_type(tint_colour(acdc_green, p = 0.2), "character")
+
+
+## Test tint colours function ----
+testthat::expect_type(tint_colours(c(acdc_green, acdc_gold), p = 0.2), "list")
+testthat::expect_type(tint_colours(c(acdc_green, acdc_gold), p = c(0.2, 0.4)), "list")
+testthat::expect_equal(
+  tint_colours(
+    c(acdc_green, acdc_gold),
+    p = c(0.2, 0.4)
+  ) |>
+    (\(x) x[[1]])() |>
+    length(),
+  2
+)
+
+
+## Test shade colours function ----
+testthat::expect_type(shade_colours(c(acdc_green, acdc_gold), p = 0.2), "list")
+testthat::expect_type(shade_colours(c(acdc_green, acdc_gold), p = c(0.2, 0.4)), "list")
+testthat::expect_equal(
+  shade_colours(
+    c(acdc_green, acdc_gold),
+    p = c(0.2, 0.4)
+  ) |>
+    (\(x) x[[1]])() |>
+    length(),
+  2
+)