Add test to show non-determinism in current code

test/version_sorter_test.rb

@@ -59,13 +59,33 @@ def test_does_not_raise_on_number_overflow
 
   def test_handles_non_version_data
     non_versions = [
-      "", " ", ".", "-", "ćevapčići", "The Quick Brown Fox", '!@#$%^&*()',
+      " ", ".", "-", "",
+      "ćevapčići", "The Quick Brown Fox", '!@#$%^&*()',
       "<--------->", "a12a8a4a22122d01541b62193e9bdad7f5eda552", "1." * 65
     ]
     sorted = [
-      "<--------->", "-", "The Quick Brown Fox",
-      "a12a8a4a22122d01541b62193e9bdad7f5eda552", "ćevapčići",
-      "", " ", ".", '!@#$%^&*()', "1." * 65
+      "<--------->", "-", "The Quick Brown Fox", "a12a8a4a22122d01541b62193e9bdad7f5eda552",
+      "ćevapčići", " ", ".", "", '!@#$%^&*()', "1." * 65
+    ]
+
+    assert_equal sorted, VersionSorter.sort(non_versions)
+  end
+
+  def test_handles_non_version_data_but_not_deterministic
+    # NOTES:
+    # - This test uses the same inputs as the previous test but
+    #   supplies them in a different order.
+    # - It also expects the same outputs in the same order.
+    # - Alas, it will fail because the sorting of non-alphanumeric
+    #   strings is currently non-deterministic.
+    non_versions = [
+      "ćevapčići", "The Quick Brown Fox", '!@#$%^&*()',
+      "<--------->", "a12a8a4a22122d01541b62193e9bdad7f5eda552", "1." * 65,
+      " ", ".", "-", ""
+    ]
+    sorted = [
+      "<--------->", "-", "The Quick Brown Fox", "a12a8a4a22122d01541b62193e9bdad7f5eda552",
+      "ćevapčići", " ", ".", "", '!@#$%^&*()', "1." * 65
     ]
 
     assert_equal sorted, VersionSorter.sort(non_versions)