1 files changed, 24 insertions, 1 deletions
diff --git a/solutions/17_tests/tests1.rs b/solutions/17_tests/tests1.rs
index 4e18198..c52b8b1 100644
--- a/solutions/17_tests/tests1.rs
+++ b/solutions/17_tests/tests1.rs
@@ -1 +1,24 @@
-// Solutions will be available before the stable release. Thank you for testing the beta version 🥰
+// Tests are important to ensure that your code does what you think it should
+// do.
+
+fn is_even(n: i64) -> bool {
+    n % 2 == 0
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    // When writing unit tests, it is common to import everything from the outer
+    // module (`super`) using a wildcard.
+    use super::*;
+
+    #[test]
+    fn you_can_assert() {
+        assert!(is_even(0));
+        assert!(!is_even(-1));
+        //      ^ You can assert `false` using the negation operator `!`.
+    }
+}