rsync code

.github/workflows/rust.yml

@@ -23,7 +23,9 @@ jobs:
         with:
           globs: "exercises/**/*.md"
       - name: Run cargo fmt
-        run: cargo fmt --all -- --check
+        run: cargo fmt --all --check
+      - name: Run rustfmt on solutions
+        run: rustfmt --check --edition 2021 --color always solutions/**/*.rs
   test:
     runs-on: ${{ matrix.os }}
     strategy:
@@ -33,7 +35,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: swatinem/rust-cache@v2
       - name: Run cargo test
-        run: cargo test
+        run: cargo test --workspace
   dev-check:
     runs-on: ubuntu-latest
     steps:

CHANGELOG.md

@@ -1,3 +1,22 @@
+<a name="6.1.0"></a>
+
+## 6.1.0 (2024-07-10)
+
+#### Added
+
+- `dev check`: Check that all exercises (including third-party ones) include at least one `TODO` comment.
+- `dev check`: Check that all exercises actually fail to run (not already solved).
+
+#### Changed
+
+- Make enum variants more consistent between enum exercises.
+- `iterators3`: Teach about the possible case of integer overflow during division.
+
+#### Fixed
+
+- Exit with a helpful error message on missing/unsupported terminal/TTY.
+- Mark the last exercise as done.
+
 <a name="6.0.1"></a>
 
 ## 6.0.1 (2024-07-04)
@@ -64,7 +83,7 @@ This should avoid issues related to the language server or to running exercises,
 Clippy lints are now shown on all exercises, not only the Clippy exercises 📎
 Make Clippy your friend from early on 🥰
 
-### Third party exercises
+### Third-party exercises
 
 Rustlings now supports third-party exercises!
 

Cargo.lock

@@ -151,9 +151,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "clap"
-version = "4.5.8"
+version = "4.5.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "84b3edb18336f4df585bc9aa31dd99c036dfa5dc5e9a2939a722a188f3a8970d"
+checksum = "64acc1846d54c1fe936a78dc189c34e28d3f5afc348403f28ecf53660b9b8462"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -161,9 +161,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.8"
+version = "4.5.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1c09dd5ada6c6c78075d6fd0da3f90d8080651e2d6cc8eb2f1aaa4034ced708"
+checksum = "6fb8393d67ba2e7bfaf28a23458e4e2b543cc73a99595511eb207fdb8aede942"
 dependencies = [
  "anstream",
  "anstyle",
@@ -354,15 +354,6 @@ version = "1.70.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8478577c03552c21db0e2724ffb8986a5ce7af88107e6be5d2ee6e158c12800"
 
-[[package]]
-name = "itertools"
-version = "0.12.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ba291022dbbd398a455acf126c1e341954079855bc60dfdda641363bd6922569"
-dependencies = [
- "either",
-]
-
 [[package]]
 name = "itertools"
 version = "0.13.0"
@@ -525,7 +516,7 @@ checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
 dependencies = [
  "cfg-if",
  "libc",
- "redox_syscall 0.5.2",
+ "redox_syscall 0.5.3",
  "smallvec",
  "windows-targets 0.52.6",
 ]
@@ -594,7 +585,7 @@ dependencies = [
  "cassowary",
  "compact_str",
  "crossterm",
- "itertools 0.13.0",
+ "itertools",
  "lru",
  "paste",
  "stability",
@@ -616,9 +607,9 @@ dependencies = [
 
 [[package]]
 name = "redox_syscall"
-version = "0.5.2"
+version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c82cf8cff14456045f55ec4241383baeff27af886adb72ffb2162f99911de0fd"
+checksum = "2a908a6e00f1fdd0dfd9c0eb08ce85126f6d8bbda50017e74bc4a4b7d4a926a4"
 dependencies = [
  "bitflags 2.6.0",
 ]
@@ -654,7 +645,7 @@ checksum = "7a66a03ae7c801facd77a29370b4faec201768915ac14a721ba36f20bc9c209b"
 
 [[package]]
 name = "rustlings"
-version = "6.0.1"
+version = "6.1.0"
 dependencies = [
  "anyhow",
  "assert_cmd",
@@ -673,7 +664,7 @@ dependencies = [
 
 [[package]]
 name = "rustlings-macros"
-version = "6.0.1"
+version = "6.1.0"
 dependencies = [
  "quote",
  "serde",
@@ -709,18 +700,18 @@ checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
 [[package]]
 name = "serde"
-version = "1.0.203"
+version = "1.0.204"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7253ab4de971e72fb7be983802300c30b5a7f0c2e56fab8abfc6a214307c0094"
+checksum = "bc76f558e0cbb2a839d37354c575f1dc3fdc6546b5be373ba43d95f231bf7c12"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.203"
+version = "1.0.204"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "500cbc0ebeb6f46627f50f3f5811ccf6bf00643be300b4c3eabc0ef55dc5b5ba"
+checksum = "e0cd7e117be63d3c3678776753929474f3b04a43a080c744d6b0ae2a8c28e222"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -785,9 +776,9 @@ checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
 
 [[package]]
 name = "stability"
-version = "0.2.0"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2ff9eaf853dec4c8802325d8b6d3dffa86cc707fd7a1a4cdbf416e13b061787a"
+checksum = "d904e7009df136af5297832a3ace3370cd14ff1546a232f4f185036c2736fcac"
 dependencies = [
  "quote",
  "syn",
@@ -829,9 +820,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.68"
+version = "2.0.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "901fa70d88b9d6c98022e23b4136f9f3e54e4662c3bc1bd1d84a42a9a0f0c1e9"
+checksum = "dc4b9b9bf2add8093d3f2c0204471e951b2285580335de42f9d2534f3ae7a8af"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -855,9 +846,9 @@ dependencies = [
 
 [[package]]
 name = "toml_edit"
-version = "0.22.14"
+version = "0.22.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f21c7aaf97f1bd9ca9d4f9e73b0a6c74bd5afef56f2bc931943a6e1c37e04e38"
+checksum = "278f3d518e152219c994ce877758516bca5e118eaed6996192a774fb9fbf0788"
 dependencies = [
  "indexmap",
  "serde",
@@ -880,11 +871,12 @@ checksum = "d4c87d22b6e3f4a18d4d40ef354e97c90fcb14dd91d7dc0aa9d8a1172ebf7202"
 
 [[package]]
 name = "unicode-truncate"
-version = "1.0.0"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a5fbabedabe362c618c714dbefda9927b5afc8e2a8102f47f081089a9019226"
+checksum = "b3644627a5af5fa321c95b9b235a72fd24cd29c648c2c379431e6628655627bf"
 dependencies = [
- "itertools 0.12.1",
+ "itertools",
+ "unicode-segmentation",
  "unicode-width",
 ]
 
@@ -1103,9 +1095,9 @@ checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
 [[package]]
 name = "winnow"
-version = "0.6.13"
+version = "0.6.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "59b5e5f6c299a3c7890b876a2a587f3115162487e704907d9b6cd29473052ba1"
+checksum = "374ec40a2d767a3c1b4972d9475ecd557356637be906f2cb3f7fe17a6eb5e22f"
 dependencies = [
  "memchr",
 ]

Cargo.toml

@@ -8,7 +8,7 @@ exclude = [
 ]
 
 [workspace.package]
-version = "6.0.1"
+version = "6.1.0"
 authors = [
   "Liv <mokou@fastmail.com>",
   "Mo Bitar <mo8it@proton.me>",
@@ -20,8 +20,8 @@ license = "MIT"
 edition = "2021"
 
 [workspace.dependencies]
-serde = { version = "1.0.203", features = ["derive"] }
+serde = { version = "1.0.204", features = ["derive"] }
-toml_edit = { version = "0.22.14", default-features = false, features = ["parse", "serde"] }
+toml_edit = { version = "0.22.16", default-features = false, features = ["parse", "serde"] }
 
 [package]
 name = "rustlings"
@@ -47,13 +47,13 @@ include = [
 
 [dependencies]
 anyhow = "1.0.86"
-clap = { version = "4.5.8", features = ["derive"] }
+clap = { version = "4.5.9", features = ["derive"] }
 crossterm = "0.27.0"
 hashbrown = "0.14.5"
 notify-debouncer-mini = { version = "0.4.1", default-features = false }
 os_pipe = "1.2.0"
 ratatui = { version = "0.27.0", default-features = false, features = ["crossterm"] }
-rustlings-macros = { path = "rustlings-macros", version = "=6.0.1" }
+rustlings-macros = { path = "rustlings-macros", version = "=6.1.0" }
 serde_json = "1.0.120"
 serde.workspace = true
 toml_edit.workspace = true

README.md

@@ -53,6 +53,21 @@ After installing Rustlings, run the following command to initialize the `rustlin
 rustlings init
 ```
 
+<details>
+<summary><strong>If the command <code>rustlings</code> can't be found…</strong> (<em>click to expand</em>)</summary>
+
+You are probably using Linux and installed Rust using your package manager.
+
+Cargo installs binaries to the directory `~/.cargo/bin`.
+Sadly, package managers often don't add `~/.cargo/bin` to your `PATH` environment variable.
+
+The solution is to …
+
+- either add `~/.cargo/bin` manually to `PATH`
+- or to uninstall Rust from the package manager and install it using the official way with `rustup`: https://www.rust-lang.org/tools/install
+
+</details>
+
 Now, go into the newly initialized directory and launch Rustlings for further instructions on getting started with the exercises:
 
 ```bash

exercises/04_primitive_types/README.md

@@ -5,5 +5,5 @@ compiler. In this section, we'll go through the most important ones.
 
 ## Further information
 
-- [Data Types](https://doc.rust-lang.org/stable/book/ch03-02-data-types.html)
+- [Data Types](https://doc.rust-lang.org/book/ch03-02-data-types.html)
-- [The Slice Type](https://doc.rust-lang.org/stable/book/ch04-03-slices.html)
+- [The Slice Type](https://doc.rust-lang.org/book/ch04-03-slices.html)

exercises/05_vecs/README.md

@@ -12,6 +12,6 @@ the other useful data structure, hash maps, later.
 
 ## Further information
 
-- [Storing Lists of Values with Vectors](https://doc.rust-lang.org/stable/book/ch08-01-vectors.html)
+- [Storing Lists of Values with Vectors](https://doc.rust-lang.org/book/ch08-01-vectors.html)
 - [`iter_mut`](https://doc.rust-lang.org/std/primitive.slice.html#method.iter_mut)
 - [`map`](https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.map)

exercises/06_move_semantics/move_semantics4.rs

@@ -8,11 +8,11 @@ mod tests {
     // Don't add, change or remove any line.
     #[test]
     fn move_semantics4() {
-        let mut x = 100;
+        let mut x = Vec::new();
         let y = &mut x;
-        *y += 100;
         let z = &mut x;
-        *z += 1000;
+        y.push(42);
-        assert_eq!(x, 1200);
+        z.push(13);
+        assert_eq!(x, [42, 13]);
     }
 }

exercises/06_move_semantics/move_semantics5.rs

@@ -3,14 +3,6 @@
 // TODO: Fix the compiler errors without changing anything except adding or
 // removing references (the character `&`).
 
-fn main() {
-    let data = "Rust is great!".to_string();
-
-    get_char(&data);
-
-    string_uppercase(data);
-}
-
 // Shouldn't take ownership
 fn get_char(data: &String) -> char {
     data.chars().last().unwrap()
@@ -22,3 +14,11 @@ fn string_uppercase(mut data: String) {
 
     println!("{data}");
 }
+
+fn main() {
+    let data = "Rust is great!".to_string();
+
+    get_char(&data);
+
+    string_uppercase(data);
+}

exercises/11_hashmaps/hashmaps2.rs

@@ -6,7 +6,7 @@
 // must add fruit to the basket so that there is at least one of each kind and
 // more than 11 in total - we have a lot of mouths to feed. You are not allowed
 // to insert any more of the fruits that are already in the basket (Apple,
-// Mango, and Lyche).
+// Mango, and Lychee).
 
 use std::collections::HashMap;
 

exercises/12_options/README.md

@@ -14,7 +14,7 @@ Option types are very common in Rust code, as they have a number of uses:
 
 ## Further Information
 
-- [Option Enum Format](https://doc.rust-lang.org/stable/book/ch10-01-syntax.html#in-enum-definitions)
+- [Option Enum Format](https://doc.rust-lang.org/book/ch10-01-syntax.html#in-enum-definitions)
 - [Option Module Documentation](https://doc.rust-lang.org/std/option/)
 - [Option Enum Documentation](https://doc.rust-lang.org/std/option/enum.Option.html)
 - [if let](https://doc.rust-lang.org/rust-by-example/flow_control/if_let.html)

exercises/13_error_handling/errors3.rs

@@ -19,6 +19,7 @@ fn main() {
     let mut tokens = 100;
     let pretend_user_input = "8";
 
+    // Don't change this line.
     let cost = total_cost(pretend_user_input).unwrap();
 
     if cost > tokens {

exercises/14_generics/README.md

@@ -7,5 +7,5 @@ The simplest and most common use of generics is for type parameters.
 
 ## Further information
 
-- [Generic Data Types](https://doc.rust-lang.org/stable/book/ch10-01-syntax.html)
+- [Generic Data Types](https://doc.rust-lang.org/book/ch10-01-syntax.html)
 - [Bounds](https://doc.rust-lang.org/rust-by-example/generics/bounds.html)

exercises/17_tests/tests3.rs

@@ -9,7 +9,7 @@ impl Rectangle {
         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");
+            panic!("Rectangle width and height must be positive");
         }
 
         Rectangle { width, height }

exercises/18_iterators/iterators3.rs

@@ -1,14 +1,20 @@
 #[derive(Debug, PartialEq, Eq)]
 enum DivisionError {
+    // Example: 42 / 0
     DivideByZero,
+    // Only case for `i64`: `i64::MIN / -1` because the result is `i64::MAX + 1`
+    IntegerOverflow,
+    // Example: 5 / 2 = 2.5
     NotDivisible,
 }
 
 // TODO: Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
 // Otherwise, return a suitable error.
-fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
+fn divide(a: i64, b: i64) -> Result<i64, DivisionError> {
     if b == 0 {
         Err(DivisionError::DivideByZero)
+    } else if (a == i64::MIN && b == -1) {
+        Err(DivisionError::IntegerOverflow)
     } else if a % b == 0 {
         Ok(a / b)
     } else {
@@ -48,6 +54,11 @@ mod tests {
         assert_eq!(divide(81, 0), Err(DivisionError::DivideByZero));
     }
 
+    #[test]
+    fn test_integer_overflow() {
+        assert_eq!(divide(i64::MIN, -1), Err(DivisionError::IntegerOverflow));
+    }
+
     #[test]
     fn test_not_divisible() {
         assert_eq!(divide(81, 6), Err(DivisionError::NotDivisible));

exercises/18_iterators/iterators4.rs

@@ -1,5 +1,8 @@
 fn factorial(num: u64) -> u64 {
-    // TODO: Complete this function to return the factorial of `num`.
+    // TODO: Complete this function to return the factorial of `num` which is
+    // defined as `1 * 2 * 3 * … * num`.
+    // https://en.wikipedia.org/wiki/Factorial
+    //
     // Do not use:
     // - early returns (using the `return` keyword explicitly)
     // Try not to use:

exercises/quizzes/quiz2.rs

@@ -26,7 +26,7 @@ enum Command {
 mod my_module {
     use super::Command;
 
-    // TODO: Complete the function.
+    // TODO: Complete the function as described above.
     pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
         input.iter().map(|(item, cmd)| {
             match cmd {

release-hook.sh

@@ -3,7 +3,12 @@
 # Error out if any command fails
 set -e
 
-cargo run -- dev check
 typos
-cargo outdated -w --exit-code 1
+cargo upgrades
+
+# Similar to CI
+cargo clippy -- --deny warnings
+cargo fmt --all --check
+rustfmt --check --edition 2021 solutions/**/*.rs
 cargo test --workspace --all-targets
+cargo run -- dev check --require-solutions

rustlings-macros/info.toml

@@ -309,7 +309,7 @@ In Rust, there are two ways to define a Vector.
    inside the square brackets. This way is simpler when you exactly know
    the initial values.
 
-Check this chapter: https://doc.rust-lang.org/stable/book/ch08-01-vectors.html
+Check this chapter: https://doc.rust-lang.org/book/ch08-01-vectors.html
 of the Rust book to learn more."""
 
 [[exercises]]
@@ -351,7 +351,7 @@ We call this "moving" a variable. When we pass `vec0` into `fill_vec`, it's
 being "moved" into `vec1`, meaning we can't access `vec0` anymore.
 
 You could make another, separate version of the data that's in `vec0` and
-pass it to `fill_vec` instead."""
+pass it to `fill_vec` instead. This is called cloning in Rust."""
 
 [[exercises]]
 name = "move_semantics3"
@@ -378,7 +378,7 @@ dir = "06_move_semantics"
 test = false
 hint = """
 To find the answer, you can consult the book section "References and Borrowing":
-https://doc.rust-lang.org/stable/book/ch04-02-references-and-borrowing.html
+https://doc.rust-lang.org/book/ch04-02-references-and-borrowing.html
 
 The first problem is that `get_char` is taking ownership of the string. So
 `data` is moved and can't be used for `string_uppercase`. `data` is moved to
@@ -416,7 +416,7 @@ to its fields.
 
 There are however some shortcuts that can be taken when instantiating structs.
 Have a look in The Book to find out more:
-https://doc.rust-lang.org/stable/book/ch05-01-defining-structs.html#creating-instances-from-other-instances-with-struct-update-syntax"""
+https://doc.rust-lang.org/book/ch05-01-defining-structs.html#creating-instances-from-other-instances-with-struct-update-syntax"""
 
 [[exercises]]
 name = "structs3"
@@ -487,7 +487,7 @@ to add one character to the `if` statement, though, that will coerce the
 Side note: If you're interested in learning about how this kind of reference
 conversion works, you can jump ahead in the book and read this part in the
 smart pointers chapter:
-https://doc.rust-lang.org/stable/book/ch15-02-deref.html#implicit-deref-coercions-with-functions-and-methods"""
+https://doc.rust-lang.org/book/ch15-02-deref.html#implicit-deref-coercions-with-functions-and-methods"""
 
 [[exercises]]
 name = "strings3"
@@ -498,7 +498,10 @@ some of them:
 https://doc.rust-lang.org/std/string/struct.String.html#method.trim
 
 For the `compose_me` method: You can either use the `format!` macro, or convert
-the string slice into an owned string, which you can then freely extend."""
+the string slice into an owned string, which you can then freely extend.
+
+For the `replace_me` method, you can check out the `replace` method:
+https://doc.rust-lang.org/std/string/struct.String.html#method.replace"""
 
 [[exercises]]
 name = "strings4"
@@ -561,7 +564,7 @@ hint = """
 Use the `entry()` and `or_insert()` methods of `HashMap` to achieve this.
 
 Learn more in The Book:
-https://doc.rust-lang.org/stable/book/ch08-03-hash-maps.html#only-inserting-a-value-if-the-key-has-no-value"""
+https://doc.rust-lang.org/book/ch08-03-hash-maps.html#only-inserting-a-value-if-the-key-has-no-value"""
 
 [[exercises]]
 name = "hashmaps3"
@@ -572,7 +575,7 @@ Hint 1: Use the `entry()` and `or_insert()` (or `or_insert_with()`) methods of
         exist in the table yet.
 
 Learn more in The Book:
-https://doc.rust-lang.org/stable/book/ch08-03-hash-maps.html#only-inserting-a-value-if-the-key-has-no-value
+https://doc.rust-lang.org/book/ch08-03-hash-maps.html#only-inserting-a-value-if-the-key-has-no-value
 
 Hint 2: If there is already an entry for a given key, the value returned by
         `entry()` can be updated based on the existing value.
@@ -585,7 +588,7 @@ https://doc.rust-lang.org/book/ch08-03-hash-maps.html#updating-a-value-based-on-
 [[exercises]]
 name = "quiz2"
 dir = "quizzes"
-hint = "No hints this time ;)"
+hint = "The `+` operator can concatenate a `String` with a `&str`."
 
 # OPTIONS
 
@@ -739,7 +742,7 @@ name = "generics2"
 dir = "14_generics"
 hint = """
 Related section in The Book:
-https://doc.rust-lang.org/stable/book/ch10-01-syntax.html#in-method-definitions"""
+https://doc.rust-lang.org/book/ch10-01-syntax.html#in-method-definitions"""
 
 # TRAITS
 
@@ -748,7 +751,9 @@ name = "traits1"
 dir = "15_traits"
 hint = """
 More about traits in The Book:
-https://doc.rust-lang.org/book/ch10-02-traits.html"""
+https://doc.rust-lang.org/book/ch10-02-traits.html
+
+The `+` operator can concatenate a `String` with a `&str`."""
 
 [[exercises]]
 name = "traits2"
@@ -869,7 +874,7 @@ We expect the method `Rectangle::new` to panic for negative values.
 To handle that, you need to add a special attribute to the test function.
 
 You can refer to the docs:
-https://doc.rust-lang.org/stable/book/ch11-01-writing-tests.html#checking-for-panics-with-should_panic"""
+https://doc.rust-lang.org/book/ch11-01-writing-tests.html#checking-for-panics-with-should_panic"""
 
 # STANDARD LIBRARY TYPES
 
@@ -888,9 +893,9 @@ hint = """
 `capitalize_first`:
 
 The variable `first` is a `char`. It needs to be capitalized and added to the
-remaining characters in `c` in order to return the correct `String`.
+remaining characters in `chars` in order to return the correct `String`.
 
-The remaining characters in `c` can be viewed as a string slice using the
+The remaining characters in `chars` can be viewed as a string slice using the
 `as_str` method.
 
 The documentation for `char` contains many useful methods.
@@ -1005,7 +1010,7 @@ thread-local copy of the numbers.
 This is a simple exercise if you understand the underlying concepts, but if this
 is too much of a struggle, consider reading through all of Chapter 16 in The
 Book:
-https://doc.rust-lang.org/stable/book/ch16-00-concurrency.html"""
+https://doc.rust-lang.org/book/ch16-00-concurrency.html"""
 
 [[exercises]]
 name = "cow1"
@@ -1143,7 +1148,11 @@ test = false
 strict_clippy = true
 hint = """
 `for` loops over `Option` values are more clearly expressed as an `if-let`
-statement."""
+statement.
+
+Not required to solve this exercise, but if you are interested in when iterating
+over `Option` can be useful, read the following section in the documentation:
+https://doc.rust-lang.org/std/option/#iterating-over-option"""
 
 [[exercises]]
 name = "clippy3"

solutions/06_move_semantics/move_semantics4.rs

@@ -7,15 +7,15 @@ mod tests {
     // TODO: Fix the compiler errors only by reordering the lines in the test.
     // Don't add, change or remove any line.
     #[test]
-    fn move_semantics5() {
+    fn move_semantics4() {
-        let mut x = 100;
+        let mut x = Vec::new();
         let y = &mut x;
         // `y` used here.
-        *y += 100;
+        y.push(42);
         // The mutable reference `y` is not used anymore,
         // therefore a new reference can be created.
         let z = &mut x;
-        *z += 1000;
+        z.push(13);
-        assert_eq!(x, 1200);
+        assert_eq!(x, [42, 13]);
     }
 }

solutions/06_move_semantics/move_semantics5.rs

@@ -1,13 +1,5 @@
 #![allow(clippy::ptr_arg)]
 
-fn main() {
-    let data = "Rust is great!".to_string();
-
-    get_char(&data);
-
-    string_uppercase(data);
-}
-
 // Borrows instead of taking ownership.
 // It is recommended to use `&str` instead of `&String` here. But this is
 // enough for now because we didn't handle strings yet.
@@ -21,3 +13,11 @@ fn string_uppercase(mut data: String) {
 
     println!("{data}");
 }
+
+fn main() {
+    let data = "Rust is great!".to_string();
+
+    get_char(&data);
+
+    string_uppercase(data);
+}

solutions/11_hashmaps/hashmaps2.rs

@@ -5,7 +5,8 @@
 // Apple (4), Mango (2) and Lychee (5) are already in the basket hash map. You
 // must add fruit to the basket so that there is at least one of each kind and
 // more than 11 in total - we have a lot of mouths to feed. You are not allowed
-// to insert any more of these fruits!
+// to insert any more of the fruits that are already in the basket (Apple,
+// Mango, and Lychee).
 
 use std::collections::HashMap;
 

solutions/17_tests/tests3.rs

@@ -9,7 +9,7 @@ impl Rectangle {
         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");
+            panic!("Rectangle width and height must be positive");
         }
 
         Rectangle { width, height }

solutions/18_iterators/iterators3.rs

@@ -1,6 +1,10 @@
 #[derive(Debug, PartialEq, Eq)]
 enum DivisionError {
+    // Example: 42 / 0
     DivideByZero,
+    // Only case for `i64`: `i64::MIN / -1` because the result is `i64::MAX + 1`
+    IntegerOverflow,
+    // Example: 5 / 2 = 2.5
     NotDivisible,
 }
 
@@ -9,6 +13,10 @@ fn divide(a: i64, b: i64) -> Result<i64, DivisionError> {
         return Err(DivisionError::DivideByZero);
     }
 
+    if a == i64::MIN && b == -1 {
+        return Err(DivisionError::IntegerOverflow);
+    }
+
     if a % b != 0 {
         return Err(DivisionError::NotDivisible);
     }
@@ -51,6 +59,11 @@ mod tests {
         assert_eq!(divide(81, 0), Err(DivisionError::DivideByZero));
     }
 
+    #[test]
+    fn test_integer_overflow() {
+        assert_eq!(divide(i64::MIN, -1), Err(DivisionError::IntegerOverflow));
+    }
+
     #[test]
     fn test_not_divisible() {
         assert_eq!(divide(81, 6), Err(DivisionError::NotDivisible));

solutions/quizzes/quiz2.rs

@@ -6,7 +6,7 @@
 // - Append "bar" to the string a specified amount of times
 //
 // The exact form of this will be:
-// - The input is going to be a vector of a 2-length tuple,
+// - The input is going to be a vector of 2-length tuples,
 //   the first element is the string, the second one is the command.
 // - The output element is going to be a vector of strings.
 

src/main.rs

@@ -2,7 +2,7 @@ use anyhow::{bail, Context, Result};
 use app_state::StateFileStatus;
 use clap::{Parser, Subcommand};
 use std::{
-    io::{self, BufRead, StdoutLock, Write},
+    io::{self, BufRead, IsTerminal, StdoutLock, Write},
     path::Path,
     process::exit,
 };
@@ -148,6 +148,10 @@ fn main() -> Result<()> {
 
     match args.command {
         None => {
+            if !io::stdout().is_terminal() {
+                bail!("Unsupported or missing terminal/TTY");
+            }
+
             let notify_exercise_names = if args.manual_run {
                 None
             } else {