diff --git a/tests/testthat/test-scale_hdx.R b/tests/testthat/test-scale_hdx.R
index 0c31b4b..7a97540 100644
--- a/tests/testthat/test-scale_hdx.R
+++ b/tests/testthat/test-scale_hdx.R
@@ -1,27 +1,37 @@
 test_that("scale_colour matches scale_color", {
+  # Scale are environments with gnarly parentage.
+  # Convert these to lists to test for equality in a more straightforward
+  # manner
+  expect_equal_scale <- function(x, y, ...) {
+    x <- as.list(x)
+    y <- as.list(y)
+    x$call <- y$call <- NULL
+    expect_equal(x, y, ...)
+  }
+
   # discrete color scales
-  expect_equal(scale_color_hdx_discrete(), scale_colour_hdx_discrete())
-  expect_equal(scale_color_hdx_mint(), scale_colour_hdx_mint())
-  expect_equal(scale_color_hdx_tomato(), scale_colour_hdx_tomato())
-  expect_equal(scale_color_hdx_sapphire(), scale_colour_hdx_sapphire())
+  expect_equal_scale(scale_color_hdx_discrete(), scale_colour_hdx_discrete())
+  expect_equal_scale(scale_color_hdx_mint(), scale_colour_hdx_mint())
+  expect_equal_scale(scale_color_hdx_tomato(), scale_colour_hdx_tomato())
+  expect_equal_scale(scale_color_hdx_sapphire(), scale_colour_hdx_sapphire())
 
   # continuous color scales
-  expect_equal(scale_color_gradient_hdx(), scale_colour_gradient_hdx())
-  expect_equal(
+  expect_equal_scale(scale_color_gradient_hdx(), scale_colour_gradient_hdx())
+  expect_equal_scale(
     scale_color_gradient_hdx_mint(),
     scale_colour_gradient_hdx_mint()
   )
-  expect_equal(
+  expect_equal_scale(
     scale_color_gradient_hdx_tomato(),
     scale_colour_gradient_hdx_tomato()
   )
-  expect_equal(
+  expect_equal_scale(
     scale_color_gradient_hdx_sapphire(),
     scale_colour_gradient_hdx_sapphire()
   )
 
   # 2 gradient scale
-  expect_equal(
+  expect_equal_scale(
     scale_color_gradient2_hdx(),
     scale_colour_gradient2_hdx()
   )