add failing test

tests/testthat/test-plot_emission_intensity.R

@@ -87,3 +87,72 @@ test_that("throws expected warning about API change", {
     class = "warning"
   )
 })
+
+test_that("works well with `scale_colour_r2dii`", {
+  #TODO: Check if this belongs here or in `test-scale_colour_r2dii.R`
+  data <- sda %>%
+    filter(region == "global")
+
+  input_levels <- c(
+    "projected",
+    "corporate_economy",
+    "target_demo",
+    "adjusted_scenario_demo"
+    )
+
+  input_color_scale <-
+    c(
+    "dark_blue",
+    "green",
+    "grey",
+    "ruby_red"
+    )
+
+  input_color_scale_hex <- data.frame(label = input_color_scale) %>%
+    left_join(palette_colours, by = "label") %>%
+    pull(hex)
+
+  expected_output <- data.frame(
+    levels = input_levels,
+    hex = input_color_scale_hex
+  )
+
+  p <- data %>%
+    dplyr::mutate(
+      emission_factor_metric = factor(
+        .data$emission_factor_metric,
+        levels = input_levels
+      )
+    ) %>%
+    plot_emission_intensity() +
+    scale_colour_r2dii(
+      labels = input_color_scale
+    )
+
+  # print the levels that colours are applied to
+  ordered_output_levels <- levels(match_lines_order(p$data))
+
+  # print the actual colour scales of the plot
+  ordered_output_colour_scale <- p$scales$get_scales("colour")$palette(
+    length(ordered_output_levels)
+    )
+
+  plot_output <- data.frame(
+    levels = ordered_output_levels,
+    hex = ordered_output_colour_scale
+  )
+
+  out <- left_join(
+    plot_output,
+    expected_output,
+    by = "levels",
+    suffix = c("_out", "_expected")
+    ) %>%
+    split(.$levels)
+
+  expect_equal(out$projected$hex_out, out$projected$hex_expected)
+  expect_equal(out$corporate_economy$hex_out, out$corporate_economy$hex_expected)
+  expect_equal(out$target_demo$hex_out, out$target_demo$hex_expected)
+  expect_equal(out$adjusted_scenario_demo$hex_out, out$adjusted_scenario_demo$hex_expected)
+
+})