Rename to TestColorProximity

test/test_color_proximity.rb

@@ -0,0 +1,23 @@
+require_relative "./helper"
+
+class TestColorProximity < Minitest::Test
+  include Linguist
+
+  def cut_hash(color)
+    color[1..-1]
+  end
+
+  def test_color_proximity
+    langs_with_colors = Language.all.reject { |language| language.color.nil? }
+    cp = ColorProximity.new(0.02, langs_with_colors.map { |lang| cut_hash(lang.color) })
+    failing_threshold = langs_with_colors.map do |lang|
+      state = cp.past_threshold?(cut_hash(lang.color))
+      if !state.first && lang.color != "##{state.last.first}"
+        "- #{lang} (#{lang.color}) is too close to #{state.last}"
+      end
+    end.compact
+    message = "The following languages have failing color thresholds. Please modify the hex color.\n#{failing_threshold.join("\n")}"
+
+    assert failing_threshold.empty?, message
+  end
+end