parallel-letter-frequency: Add "Unicode letters" test

Author: ellnix

exercises/practice/parallel-letter-frequency/.meta/tests.toml

@@ -41,7 +41,6 @@ rust_fn = "numbers_dont_count"
 
 [aa9f97ac-3961-4af1-88e7-6efed1bfddfd]
 description = "Unicode letters"
-rust_fn = "all_three_anthems_1_worker"
 
 [7b1da046-701b-41fc-813e-dcfb5ee51813]
 description = "combination of lower- and uppercase letters, punctuation and white space"

exercises/practice/parallel-letter-frequency/tests/parallel_letter_frequency.rs

@@ -125,6 +125,18 @@ fn numbers_dont_count() {
     assert!(!frequency::frequency(&["Testing, 1, 2, 3"], 4).contains_key(&'1'));
 }
 
+#[test]
+#[ignore]
+fn unicode_letters() {
+    let mut hm = HashMap::new();
+    hm.insert('本', 1);
+    hm.insert('φ', 1);
+    hm.insert('ほ', 1);
+    hm.insert('ø', 1);
+    let v = ["本", "φ", "ほ", "ø"];
+    assert_eq!(frequency::frequency(&v, 4), hm);
+}
+
 #[test]
 #[ignore]
 fn all_three_anthems_1_worker() {