4 files changed, 62 insertions, 82 deletions
diff --git a/exercises/17_tests/tests1.rs b/exercises/17_tests/tests1.rs
index 810277a..7529f9f 100644
--- a/exercises/17_tests/tests1.rs
+++ b/exercises/17_tests/tests1.rs
@@ -1,21 +1,23 @@
-// tests1.rs
-//
 // Tests are important to ensure that your code does what you think it should
-// do. Tests can be run on this file with the following command: rustlings run
-// tests1
-//
-// This test has a problem with it -- make the test compile! Make the test pass!
-// Make the test fail!
-//
-// Execute `rustlings hint tests1` or use the `hint` watch subcommand for a
-// hint.
+// do.
 
-// I AM NOT DONE
+fn is_even(n: i64) -> bool {
+    n % 2 == 0
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
 
 #[cfg(test)]
 mod tests {
+    // TODO: Import `is_even`. You can use a wildcard to import everything in
+    // the outer module.
+
     #[test]
     fn you_can_assert() {
+        // TODO: Test the function `is_even` with some values.
+        assert!();
         assert!();
     }
 }
diff --git a/exercises/17_tests/tests2.rs b/exercises/17_tests/tests2.rs
index f8024e9..0c6573e 100644
--- a/exercises/17_tests/tests2.rs
+++ b/exercises/17_tests/tests2.rs
@@ -1,17 +1,23 @@
-// tests2.rs
-//
-// This test has a problem with it -- make the test compile! Make the test pass!
-// Make the test fail!
-//
-// Execute `rustlings hint tests2` or use the `hint` watch subcommand for a
-// hint.
+// Calculates the power of 2 using a bit shift.
+// `1 << n` is equivalent to "2 to the power of n".
+fn power_of_2(n: u8) -> u64 {
+    1 << n
+}
 
-// I AM NOT DONE
+fn main() {
+    // You can optionally experiment here.
+}
 
 #[cfg(test)]
 mod tests {
+    use super::*;
+
     #[test]
     fn you_can_assert_eq() {
+        // TODO: Test the function `power_of_2` with some values.
+        assert_eq!();
+        assert_eq!();
+        assert_eq!();
         assert_eq!();
     }
 }
diff --git a/exercises/17_tests/tests3.rs b/exercises/17_tests/tests3.rs
index 4013e38..ec99479 100644
--- a/exercises/17_tests/tests3.rs
+++ b/exercises/17_tests/tests3.rs
@@ -1,16 +1,23 @@
-// tests3.rs
-//
-// This test isn't testing our function -- make it do that in such a way that
-// the test passes. Then write a second test that tests whether we get the
-// result we expect to get when we call `is_even(5)`.
-//
-// Execute `rustlings hint tests3` or use the `hint` watch subcommand for a
-// hint.
+struct Rectangle {
+    width: i32,
+    height: i32,
+}
+
+impl Rectangle {
+    // Don't change this function.
+    fn new(width: i32, height: i32) -> Self {
+        if width <= 0 || height <= 0 {
+            // Returning a `Result` would be better here. But we want to learn
+            // how to test functions that can panic.
+            panic!("Rectangle width and height can't be negative");
+        }
 
-// I AM NOT DONE
+        Rectangle { width, height }
+    }
+}
 
-pub fn is_even(num: i32) -> bool {
-    num % 2 == 0
+fn main() {
+    // You can optionally experiment here.
 }
 
 #[cfg(test)]
@@ -18,12 +25,25 @@ mod tests {
     use super::*;
 
     #[test]
-    fn is_true_when_even() {
-        assert!();
+    fn correct_width_and_height() {
+        // TODO: This test should check if the rectangle has the size that we
+        // pass to its constructor.
+        let rect = Rectangle::new(10, 20);
+        assert_eq!(todo!(), 10); // Check width
+        assert_eq!(todo!(), 20); // Check height
+    }
+
+    // TODO: This test should check if the program panics when we try to create
+    // a rectangle with negative width.
+    #[test]
+    fn negative_width() {
+        let _rect = Rectangle::new(-10, 10);
     }
 
+    // TODO: This test should check if the program panics when we try to create
+    // a rectangle with negative height.
     #[test]
-    fn is_false_when_odd() {
-        assert!();
+    fn negative_height() {
+        let _rect = Rectangle::new(10, -10);
     }
 }
diff --git a/exercises/17_tests/tests4.rs b/exercises/17_tests/tests4.rs
deleted file mode 100644
index 935d0db..0000000
--- a/exercises/17_tests/tests4.rs
+++ /dev/null
@@ -1,48 +0,0 @@
-// tests4.rs
-//
-// Make sure that we're testing for the correct conditions!
-//
-// Execute `rustlings hint tests4` or use the `hint` watch subcommand for a
-// hint.
-
-// I AM NOT DONE
-
-struct Rectangle {
-    width: i32,
-    height: i32
-}
-
-impl Rectangle {
-    // Only change the test functions themselves
-    pub fn new(width: i32, height: i32) -> Self {
-        if width <= 0 || height <= 0 {
-            panic!("Rectangle width and height cannot be negative!")
-        }
-        Rectangle {width, height}
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn correct_width_and_height() {
-        // This test should check if the rectangle is the size that we pass into its constructor
-        let rect = Rectangle::new(10, 20);
-        assert_eq!(???, 10); // check width
-        assert_eq!(???, 20); // check height
-    }
-
-    #[test]
-    fn negative_width() {
-        // This test should check if program panics when we try to create rectangle with negative width
-        let _rect = Rectangle::new(-10, 10);
-    }
-
-    #[test]
-    fn negative_height() {
-        // This test should check if program panics when we try to create rectangle with negative height
-        let _rect = Rectangle::new(10, -10);
-    }
-}