diff --git a/exercises/luhn/Cargo.toml b/exercises/luhn/Cargo.toml
index af784656b..6b54be8b0 100644
--- a/exercises/luhn/Cargo.toml
+++ b/exercises/luhn/Cargo.toml
@@ -1,4 +1,4 @@
 [package]
 edition = "2018"
 name = "luhn"
-version = "1.3.0"
+version = "1.6.1"
diff --git a/exercises/luhn/tests/luhn.rs b/exercises/luhn/tests/luhn.rs
index 0915cdf73..0f72f2638 100644
--- a/exercises/luhn/tests/luhn.rs
+++ b/exercises/luhn/tests/luhn.rs
@@ -1,90 +1,127 @@
 use luhn::*;
 
+fn process_valid_case(number: &str, is_luhn_expected: bool) {
+    assert_eq!(is_valid(number), is_luhn_expected);
+}
+
 #[test]
-fn single_digit_string_is_invalid() {
-    assert!(!is_valid("1"));
+fn test_single_digit_strings_can_not_be_valid() {
+    process_valid_case("1", false);
 }
 
 #[test]
 #[ignore]
-fn single_zero_string_is_invalid() {
-    assert!(!is_valid("0"));
+fn test_a_single_zero_is_invalid() {
+    process_valid_case("0", false);
 }
 
 #[test]
 #[ignore]
-fn simple_valid_sin_that_remains_valid_if_reversed() {
-    assert!(is_valid("059"));
+fn test_a_simple_valid_sin_that_remains_valid_if_reversed() {
+    process_valid_case("059", true);
 }
 
 #[test]
 #[ignore]
-fn simple_valid_sin_that_becomes_invalid_if_reversed() {
-    assert!(is_valid("59"));
+fn test_a_simple_valid_sin_that_becomes_invalid_if_reversed() {
+    process_valid_case("59", true);
 }
 
 #[test]
 #[ignore]
-fn valid_canadian_sin_is_valid() {
-    assert!(is_valid("055 444 285"));
+fn test_a_valid_canadian_sin() {
+    process_valid_case("055 444 285", true);
 }
 
 #[test]
 #[ignore]
-fn invalid_canadian_sin_is_invalid() {
-    assert!(!is_valid("055 444 286"));
+fn test_invalid_canadian_sin() {
+    process_valid_case("055 444 286", false);
 }
 
 #[test]
 #[ignore]
-fn invalid_credit_card_is_invalid() {
-    assert!(!is_valid("8273 1232 7352 0569"));
+fn test_invalid_credit_card() {
+    process_valid_case("8273 1232 7352 0569", false);
 }
 
 #[test]
 #[ignore]
-fn valid_number_with_an_even_number_of_digits() {
-    assert!(is_valid("095 245 88"));
+fn test_valid_number_with_an_even_number_of_digits() {
+    process_valid_case("095 245 88", true);
 }
 
 #[test]
 #[ignore]
 fn strings_that_contain_non_digits_are_invalid() {
-    assert!(!is_valid("055a 444 285"));
+    process_valid_case("055a 444 285", false);
 }
 
 #[test]
 #[ignore]
-fn punctuation_is_invalid() {
-    assert!(!is_valid("055-444-285"));
+fn test_valid_strings_with_punctuation_included_become_invalid() {
+    process_valid_case("055-444-285", false);
 }
 
 #[test]
 #[ignore]
 fn symbols_are_invalid() {
-    assert!(!is_valid("055£ 444$ 285"));
+    process_valid_case("055£ 444$ 285", false);
+}
+
+#[test]
+#[ignore]
+fn test_single_zero_with_space_is_invalid() {
+    process_valid_case(" 0", false);
+}
+
+#[test]
+#[ignore]
+fn test_more_than_a_single_zero_is_valid() {
+    process_valid_case("0000 0", true);
+}
+
+#[test]
+#[ignore]
+fn test_input_digit_9_is_correctly_converted_to_output_digit_9() {
+    process_valid_case("091", true);
+}
+
+#[test]
+#[ignore]
+/// using ascii value for doubled non-digit isn't allowed
+/// Convert non-digits to their ascii values and then offset them by 48 sometimes accidentally declare an invalid string to be valid.
+/// This test is designed to avoid that solution.
+fn test_using_ascii_value_for_doubled_nondigit_isnt_allowed() {
+    process_valid_case(":9", false);
 }
 
 #[test]
 #[ignore]
-fn single_digit_with_space_is_invalid() {
-    assert!(!is_valid(" 0"));
+/// valid strings with a non-digit added at the end become invalid
+fn test_valid_strings_with_a_nondigit_added_at_the_end_become_invalid() {
+    process_valid_case("059a", false);
 }
 
 #[test]
 #[ignore]
-fn more_than_a_single_zero_is_valid() {
-    assert!(is_valid("0000 0"));
+/// valid strings with symbols included become invalid
+fn test_valid_strings_with_symbols_included_become_invalid() {
+    process_valid_case("055# 444$ 285", false);
 }
 
 #[test]
 #[ignore]
-fn input_digit_9_is_correctly_converted_to_output_digit_9() {
-    assert!(is_valid("091"));
+/// using ascii value for non-doubled non-digit isn't allowed
+/// Convert non-digits to their ascii values and then offset them by 48 sometimes accidentally declare an invalid string to be valid.
+/// This test is designed to avoid that solution.
+fn test_using_ascii_value_for_nondoubled_nondigit_isnt_allowed() {
+    process_valid_case("055b 444 285", false);
 }
 
 #[test]
 #[ignore]
-fn non_digit_isnt_converted_to_digit_by_ascii_value() {
-    assert!(!is_valid(":9"));
+/// valid number with an odd number of spaces
+fn test_valid_number_with_an_odd_number_of_spaces() {
+    process_valid_case("234 567 891 234", true);
 }