rustlings: complete 15

13 files changed, 249 insertions, 20 deletions

diff --git a/rustlings/.rustlings-state.txt b/rustlings/.rustlings-state.txt
index 163f806..888d577 100644
--- a/rustlings/.rustlings-state.txt
+++ b/rustlings/.rustlings-state.txt
@@ -1,6 +1,6 @@
 DON'T EDIT THIS FILE!
 
-traits1
+lifetimes1
 
 intro1
 intro2
@@ -59,4 +59,10 @@ errors4
 errors5
 errors6
 generics1
-generics2
\ No newline at end of file
+generics2
+traits1
+traits2
+traits3
+traits4
+traits5
+quiz3
\ No newline at end of file
diff --git a/rustlings/exercises/15_traits/traits1.rs b/rustlings/exercises/15_traits/traits1.rs
index 85be17e..fad6a50 100644
--- a/rustlings/exercises/15_traits/traits1.rs
+++ b/rustlings/exercises/15_traits/traits1.rs
@@ -6,6 +6,9 @@ trait AppendBar {
 
 impl AppendBar for String {
     // TODO: Implement `AppendBar` for the type `String`.
+    fn append_bar(self) -> Self {
+        self + "Bar"
+    }
 }
 
 fn main() {
diff --git a/rustlings/exercises/15_traits/traits2.rs b/rustlings/exercises/15_traits/traits2.rs
index d724dc2..5dfc36d 100644
--- a/rustlings/exercises/15_traits/traits2.rs
+++ b/rustlings/exercises/15_traits/traits2.rs
@@ -5,6 +5,14 @@ trait AppendBar {
 // TODO: Implement the trait `AppendBar` for a vector of strings.
 // `append_bar` should push the string "Bar" into the vector.
 
+impl AppendBar for Vec<String> {
+    fn append_bar(self) -> Self {
+        let mut s = self.clone();
+        s.push(String::from("Bar"));
+        s
+    }
+}
+
 fn main() {
     // You can optionally experiment here.
 }
diff --git a/rustlings/exercises/15_traits/traits3.rs b/rustlings/exercises/15_traits/traits3.rs
index c244650..144ac0a 100644
--- a/rustlings/exercises/15_traits/traits3.rs
+++ b/rustlings/exercises/15_traits/traits3.rs
@@ -3,7 +3,9 @@ trait Licensed {
     // implementors like the two structs below can share that default behavior
     // without repeating the function.
     // The default license information should be the string "Default license".
-    fn licensing_info(&self) -> String;
+    fn licensing_info(&self) -> String {
+        String::from("Default license")
+    }
 }
 
 struct SomeSoftware {
diff --git a/rustlings/exercises/15_traits/traits4.rs b/rustlings/exercises/15_traits/traits4.rs
index 80092a6..b23dcdd 100644
--- a/rustlings/exercises/15_traits/traits4.rs
+++ b/rustlings/exercises/15_traits/traits4.rs
@@ -11,7 +11,7 @@ impl Licensed for SomeSoftware {}
 impl Licensed for OtherSoftware {}
 
 // TODO: Fix the compiler error by only changing the signature of this function.
-fn compare_license_types(software1: ???, software2: ???) -> bool {
+fn compare_license_types(software1: impl Licensed, software2: impl Licensed) -> bool {
     software1.licensing_info() == software2.licensing_info()
 }
 
diff --git a/rustlings/exercises/15_traits/traits5.rs b/rustlings/exercises/15_traits/traits5.rs
index 5b356ac..6548014 100644
--- a/rustlings/exercises/15_traits/traits5.rs
+++ b/rustlings/exercises/15_traits/traits5.rs
@@ -19,7 +19,7 @@ impl SomeTrait for OtherStruct {}
 impl OtherTrait for OtherStruct {}
 
 // TODO: Fix the compiler error by only changing the signature of this function.
-fn some_func(item: ???) -> bool {
+fn some_func<T : SomeTrait + OtherTrait>(item: T) -> bool {
     item.some_function() && item.other_function()
 }
 
diff --git a/rustlings/exercises/quizzes/quiz3.rs b/rustlings/exercises/quizzes/quiz3.rs
index c877c5f..5bb859f 100644
--- a/rustlings/exercises/quizzes/quiz3.rs
+++ b/rustlings/exercises/quizzes/quiz3.rs
@@ -12,14 +12,14 @@
 // block to support alphabetical report cards in addition to numerical ones.
 
 // TODO: Adjust the struct as described above.
-struct ReportCard {
-    grade: f32,
+struct ReportCard<T> {
+    grade: T,
     student_name: String,
     student_age: u8,
 }
 
 // TODO: Adjust the impl block as described above.
-impl ReportCard {
+impl<T: std::fmt::Display> ReportCard<T> {
     fn print(&self) -> String {
         format!(
             "{} ({}) - achieved a grade of {}",
diff --git a/rustlings/solutions/15_traits/traits1.rs b/rustlings/solutions/15_traits/traits1.rs
index dcf2377..790873f 100644
--- a/rustlings/solutions/15_traits/traits1.rs
+++ b/rustlings/solutions/15_traits/traits1.rs
@@ -1,4 +1,32 @@
+// The trait `AppendBar` has only one function which appends "Bar" to any object
+// implementing this trait.
+trait AppendBar {
+    fn append_bar(self) -> Self;
+}
+
+impl AppendBar for String {
+    fn append_bar(self) -> Self {
+        self + "Bar"
+    }
+}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    let s = String::from("Foo");
+    let s = s.append_bar();
+    println!("s: {s}");
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_foo_bar() {
+        assert_eq!(String::from("Foo").append_bar(), "FooBar");
+    }
+
+    #[test]
+    fn is_bar_bar() {
+        assert_eq!(String::from("").append_bar().append_bar(), "BarBar");
+    }
 }
diff --git a/rustlings/solutions/15_traits/traits2.rs b/rustlings/solutions/15_traits/traits2.rs
index dcf2377..0db93e0 100644
--- a/rustlings/solutions/15_traits/traits2.rs
+++ b/rustlings/solutions/15_traits/traits2.rs
@@ -1,4 +1,27 @@
+trait AppendBar {
+    fn append_bar(self) -> Self;
+}
+
+impl AppendBar for Vec<String> {
+    fn append_bar(mut self) -> Self {
+        //        ^^^ this is important
+        self.push(String::from("Bar"));
+        self
+    }
+}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_vec_pop_eq_bar() {
+        let mut foo = vec![String::from("Foo")].append_bar();
+        assert_eq!(foo.pop().unwrap(), "Bar");
+        assert_eq!(foo.pop().unwrap(), "Foo");
+    }
 }
diff --git a/rustlings/solutions/15_traits/traits3.rs b/rustlings/solutions/15_traits/traits3.rs
index dcf2377..3d8ec85 100644
--- a/rustlings/solutions/15_traits/traits3.rs
+++ b/rustlings/solutions/15_traits/traits3.rs
@@ -1,4 +1,36 @@
+trait Licensed {
+    fn licensing_info(&self) -> String {
+        "Default license".to_string()
+    }
+}
+
+struct SomeSoftware {
+    version_number: i32,
+}
+
+struct OtherSoftware {
+    version_number: String,
+}
+
+impl Licensed for SomeSoftware {}
+impl Licensed for OtherSoftware {}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_licensing_info_the_same() {
+        let licensing_info = "Default license";
+        let some_software = SomeSoftware { version_number: 1 };
+        let other_software = OtherSoftware {
+            version_number: "v2.0.0".to_string(),
+        };
+        assert_eq!(some_software.licensing_info(), licensing_info);
+        assert_eq!(other_software.licensing_info(), licensing_info);
+    }
 }
diff --git a/rustlings/solutions/15_traits/traits4.rs b/rustlings/solutions/15_traits/traits4.rs
index dcf2377..3675b8d 100644
--- a/rustlings/solutions/15_traits/traits4.rs
+++ b/rustlings/solutions/15_traits/traits4.rs
@@ -1,4 +1,35 @@
+trait Licensed {
+    fn licensing_info(&self) -> String {
+        "Default license".to_string()
+    }
+}
+
+struct SomeSoftware;
+struct OtherSoftware;
+
+impl Licensed for SomeSoftware {}
+impl Licensed for OtherSoftware {}
+
+fn compare_license_types(software1: impl Licensed, software2: impl Licensed) -> bool {
+    //                              ^^^^^^^^^^^^^             ^^^^^^^^^^^^^
+    software1.licensing_info() == software2.licensing_info()
+}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn compare_license_information() {
+        assert!(compare_license_types(SomeSoftware, OtherSoftware));
+    }
+
+    #[test]
+    fn compare_license_information_backwards() {
+        assert!(compare_license_types(OtherSoftware, SomeSoftware));
+    }
 }
diff --git a/rustlings/solutions/15_traits/traits5.rs b/rustlings/solutions/15_traits/traits5.rs
index dcf2377..1fb426a 100644
--- a/rustlings/solutions/15_traits/traits5.rs
+++ b/rustlings/solutions/15_traits/traits5.rs
@@ -1,4 +1,39 @@
+trait SomeTrait {
+    fn some_function(&self) -> bool {
+        true
+    }
+}
+
+trait OtherTrait {
+    fn other_function(&self) -> bool {
+        true
+    }
+}
+
+struct SomeStruct;
+impl SomeTrait for SomeStruct {}
+impl OtherTrait for SomeStruct {}
+
+struct OtherStruct;
+impl SomeTrait for OtherStruct {}
+impl OtherTrait for OtherStruct {}
+
+fn some_func(item: impl SomeTrait + OtherTrait) -> bool {
+    //             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+    item.some_function() && item.other_function()
+}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_some_func() {
+        assert!(some_func(SomeStruct));
+        assert!(some_func(OtherStruct));
+    }
 }
diff --git a/rustlings/solutions/quizzes/quiz3.rs b/rustlings/solutions/quizzes/quiz3.rs
index dcf2377..7b91278 100644
--- a/rustlings/solutions/quizzes/quiz3.rs
+++ b/rustlings/solutions/quizzes/quiz3.rs
@@ -1,4 +1,65 @@
+// An imaginary magical school has a new report card generation system written
+// in Rust! Currently, the system only supports creating report cards where the
+// student's grade is represented numerically (e.g. 1.0 -> 5.5). However, the
+// school also issues alphabetical grades (A+ -> F-) and needs to be able to
+// print both types of report card!
+//
+// Make the necessary code changes in the struct `ReportCard` and the impl
+// block to support alphabetical report cards in addition to numerical ones.
+
+use std::fmt::Display;
+
+// Make the struct generic over `T`.
+struct ReportCard<T> {
+    //           ^^^
+    grade: T,
+    //     ^
+    student_name: String,
+    student_age: u8,
+}
+
+// To be able to print the grade, it has to implement the `Display` trait.
+impl<T: Display> ReportCard<T> {
+    //  ^^^^^^^ require that `T` implements `Display`.
+    fn print(&self) -> String {
+        format!(
+            "{} ({}) - achieved a grade of {}",
+            &self.student_name, &self.student_age, &self.grade,
+        )
+    }
+}
+
 fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn generate_numeric_report_card() {
+        let report_card = ReportCard {
+            grade: 2.1,
+            student_name: "Tom Wriggle".to_string(),
+            student_age: 12,
+        };
+        assert_eq!(
+            report_card.print(),
+            "Tom Wriggle (12) - achieved a grade of 2.1",
+        );
+    }
+
+    #[test]
+    fn generate_alphabetic_report_card() {
+        let report_card = ReportCard {
+            grade: "A+",
+            student_name: "Gary Plotter".to_string(),
+            student_age: 11,
+        };
+        assert_eq!(
+            report_card.print(),
+            "Gary Plotter (11) - achieved a grade of A+",
+        );
+    }
 }