adds a test to make sure Tidy runs Schlinkert pruning the reversed list

tests/pruning_tests.rs

@@ -0,0 +1,37 @@
+mod pruning_tests {
+    use tidy::display_information::uniquely_decodable::check_decodability;
+    use tidy::*;
+
+    #[test]
+    fn can_run_schlinkert_prune_on_reversed_list_if_it_saves_more_words() {
+        let list: Vec<String> = vec![
+            "news",
+            "paper",
+            "newspaper",
+            "donkey",
+            "newsdonkey",
+            "ghost",
+            "newsghost",
+            "radish",
+            "newsradish",
+        ]
+        .iter()
+        .map(|w| w.to_string())
+        .collect();
+
+        let this_tidy_request = TidyRequest {
+            list: list,
+            should_schlinkert_prune: true,
+            ..Default::default()
+        };
+        let new_list = tidy_list(this_tidy_request);
+        // If Schlinkert prune was done in forwards, only
+        // 5 words would be saved. But if we Schlinkert
+        // prune the reversed list, we save 8 words.
+        assert!(new_list.len() == 8);
+        // And now let's confirm that the new list is indeed
+        // uniquely decodable, at least as far as Tidy is able
+        // to confirm.
+        assert!(check_decodability(&new_list));
+    }
+}