Merge e59c65cf45 into 0432e07864

Fix typos

Cargo.lock

@@ -2,18 +2,6 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "ahash"
-version = "0.8.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e89da841a80418a9b391ebaea17f5c112ffaaa96f621d2c285b5174da76b9011"
-dependencies = [
- "cfg-if",
- "once_cell",
- "version_check",
- "zerocopy",
-]
-
 [[package]]
 name = "anstream"
 version = "0.6.15"
@@ -71,9 +59,9 @@ checksum = "86fdf8605db99b54d3cd748a44c6d04df638eb5dafb219b135d0149bd0db01f6"
 
 [[package]]
 name = "autocfg"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
 
 [[package]]
 name = "bitflags"
@@ -95,9 +83,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "clap"
-version = "4.5.18"
+version = "4.5.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b0956a43b323ac1afaffc053ed5c4b7c1f1800bacd1683c353aabbb752515dd3"
+checksum = "b97f376d85a664d5837dbae44bf546e6477a679ff6610010f17276f686d867e8"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -105,9 +93,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.18"
+version = "4.5.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4d72166dd41634086d5803a47eb71ae740e61d84709c36f3c34110173db3961b"
+checksum = "19bc80abd44e4bed93ca373a0704ccbd1b710dc5749406201bb018272808dc54"
 dependencies = [
  "anstream",
  "anstyle",
@@ -198,6 +186,12 @@ dependencies = [
  "windows-sys 0.59.0",
 ]
 
+[[package]]
+name = "foldhash"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f81ec6369c545a7d40e4589b5597581fa1c441fe1cce96dd1de43159910a36a2"
+
 [[package]]
 name = "fsevent-sys"
 version = "4.1.0"
@@ -209,9 +203,9 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.14.5"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
+checksum = "1e087f84d4f86bf4b218b927129862374b72199ae7d8657835f1e89000eea4fb"
 
 [[package]]
 name = "heck"
@@ -227,9 +221,9 @@ checksum = "d231dfb89cfffdbc30e7fc41579ed6066ad03abda9e567ccafae602b97ec5024"
 
 [[package]]
 name = "indexmap"
-version = "2.5.0"
+version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68b900aa2f7301e21c36462b170ee99994de34dff39a4a6a528e80e7376d07e5"
+checksum = "707907fe3c25f5424cce2cb7e1cbcafee6bdbe735ca90ef77c29e84591e5b9da"
 dependencies = [
  "equivalent",
  "hashbrown",
@@ -377,9 +371,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.19.0"
+version = "1.20.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
+checksum = "1261fe7e33c73b354eab43b1273a57c8f967d0391e80353e51f764ac02cf6775"
 
 [[package]]
 name = "os_pipe"
@@ -416,9 +410,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.86"
+version = "1.0.87"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+checksum = "b3e4daa0dcf6feba26f985457cdf104d4b4256fc5a09547140f3631bb076b19a"
 dependencies = [
  "unicode-ident",
 ]
@@ -434,9 +428,9 @@ dependencies = [
 
 [[package]]
 name = "redox_syscall"
-version = "0.5.6"
+version = "0.5.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "355ae415ccd3a04315d3f8246e86d67689ea74d88d915576e1589a351062a13b"
+checksum = "9b6dfecf2c74bce2466cabf93f6664d6998a69eb21e39f4207930065b27b771f"
 dependencies = [
  "bitflags 2.6.0",
 ]
@@ -458,10 +452,10 @@ dependencies = [
 name = "rustlings"
 version = "6.3.0"
 dependencies = [
- "ahash",
  "anyhow",
  "clap",
  "crossterm",
+ "foldhash",
  "notify",
  "os_pipe",
  "rustix",
@@ -587,9 +581,9 @@ checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
 name = "syn"
-version = "2.0.77"
+version = "2.0.79"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f35bcdf61fd8e7be6caf75f429fdca8beb3ed76584befb503b1569faee373ed"
+checksum = "89132cd0bf050864e1d38dc3bbc07a0eb8e7530af26344d3d2bbbef83499f590"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -598,9 +592,9 @@ dependencies = [
 
 [[package]]
 name = "tempfile"
-version = "3.12.0"
+version = "3.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04cbcdd0c794ebb0d4cf35e88edd2f7d2c4c3e9a5a6dab322839b321c6a87a64"
+checksum = "f0f2c9fc62d0beef6951ccffd757e241266a2c833136efbe35af6cd2567dca5b"
 dependencies = [
  "cfg-if",
  "fastrand",
@@ -643,12 +637,6 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
 
-[[package]]
-name = "version_check"
-version = "0.9.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
-
 [[package]]
 name = "walkdir"
 version = "2.5.0"
@@ -852,23 +840,3 @@ checksum = "36c1fec1a2bb5866f07c25f68c26e565c4c200aebb96d7e55710c19d3e8ac49b"
 dependencies = [
  "memchr",
 ]
-
-[[package]]
-name = "zerocopy"
-version = "0.7.35"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
-dependencies = [
- "zerocopy-derive",
-]
-
-[[package]]
-name = "zerocopy-derive"
-version = "0.7.35"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]

Cargo.toml

@@ -46,10 +46,10 @@ include = [
 ]
 
 [dependencies]
-ahash = { version = "0.8.11", default-features = false }
 anyhow = "1.0.89"
-clap = { version = "4.5.18", features = ["derive"] }
+clap = { version = "4.5.20", features = ["derive"] }
 crossterm = { version = "0.28.1", default-features = false, features = ["windows", "events"] }
+foldhash = "0.1.3"
 notify = { version = "6.1.1", default-features = false, features = ["macos_fsevent"] }
 os_pipe = "1.2.1"
 rustlings-macros = { path = "rustlings-macros", version = "=6.3.0" }
@@ -61,7 +61,7 @@ toml_edit.workspace = true
 rustix = { version = "0.38.37", default-features = false, features = ["std", "stdio", "termios"] }
 
 [dev-dependencies]
-tempfile = "3.12.0"
+tempfile = "3.13.0"
 
 [profile.release]
 panic = "abort"

clippy.toml

@@ -5,7 +5,7 @@ disallowed-types = [
 ]
 
 disallowed-methods = [
-  # We use `ahash` instead of the default hasher.
+  # We use `foldhash` instead of the default hasher.
   "std::collections::HashSet::new",
   "std::collections::HashSet::with_capacity",
   # Inefficient. Use `.queue(…)` instead.

dev/Cargo.toml

@@ -26,6 +26,8 @@ bin = [
   { name = "functions4_sol", path = "../solutions/02_functions/functions4.rs" },
   { name = "functions5", path = "../exercises/02_functions/functions5.rs" },
   { name = "functions5_sol", path = "../solutions/02_functions/functions5.rs" },
+  { name = "functions6", path = "../exercises/02_functions/functions6.rs" },
+  { name = "functions6_sol", path = "../solutions/02_functions/functions6.rs" },
   { name = "if1", path = "../exercises/03_if/if1.rs" },
   { name = "if1_sol", path = "../solutions/03_if/if1.rs" },
   { name = "if2", path = "../exercises/03_if/if2.rs" },
@@ -60,6 +62,8 @@ bin = [
   { name = "move_semantics4_sol", path = "../solutions/06_move_semantics/move_semantics4.rs" },
   { name = "move_semantics5", path = "../exercises/06_move_semantics/move_semantics5.rs" },
   { name = "move_semantics5_sol", path = "../solutions/06_move_semantics/move_semantics5.rs" },
+  { name = "move_semantics6", path = "../exercises/06_move_semantics/move_semantics6.rs" },
+  { name = "move_semantics6_sol", path = "../solutions/06_move_semantics/move_semantics6.rs" },
   { name = "structs1", path = "../exercises/07_structs/structs1.rs" },
   { name = "structs1_sol", path = "../solutions/07_structs/structs1.rs" },
   { name = "structs2", path = "../exercises/07_structs/structs2.rs" },

exercises/02_functions/README.md

@@ -1,8 +1,9 @@
 # Functions
 
 Here, you'll learn how to write functions and how the Rust compiler can help you debug errors even
-in more complex code.
+in more complex code. You will also learn what is the difference with closures.
 
 ## Further information
 
 - [How Functions Work](https://doc.rust-lang.org/book/ch03-03-how-functions-work.html)
+- [Closures](https://doc.rust-lang.org/book/ch13-01-closures.html)

exercises/02_functions/functions6.rs

@@ -0,0 +1,19 @@
+// functions6.rs
+//
+// Here you can practice special functions called `closures`, that can capture
+// variables of their parent context.
+// Fix the code below to make it compile, without changing the two closure
+// definitions.
+//
+// Execute `rustlings hint functions6` or use the `hint` watch subcommand for
+// some hints.
+
+fn main() {
+  // TODO: ensure the definition of captured variable
+  let closure_1 = |input_var: u32| -> u32 {input_var + outer_var};
+  println!("Closure#1 returns {}", closure_1(5));
+
+  let closure_2 = |input_var| println!("Closure#2 (input_var {})", input_var);
+  closure_2(2);
+  closure_2("5"); // TODO: look at the captured variable type here
+}

exercises/06_move_semantics/move_semantics6.rs

@@ -0,0 +1,25 @@
+// move_semantics6.rs
+//
+// Here you will practice how mutable/immutable borrowing works in the context
+// of a closure.
+//
+// Try to fix this code to make it compile and not panic.
+// You can't change anything except removing 1 line.
+//
+// Execute `rustlings hint move_semantics7` or use the `hint` watch subcommand
+// for a hint.
+
+fn main() {
+  let mut counter = 0;
+
+  let mut increment = || {
+    counter += 1;
+    println!("counter equals {}", counter);
+  };
+
+  increment();
+  let _reborrowed_counter = &counter; // TODO: figure out where to put this borrowing instruction
+  increment();
+
+  assert_eq!(counter, 2);
+}

exercises/README.md

@@ -3,7 +3,7 @@
 | Exercise               | Book Chapter        |
 | ---------------------- | ------------------- |
 | variables              | §3.1                |
-| functions              | §3.3                |
+| functions              | §3.3, §13.1         |
 | if                     | §3.5                |
 | primitive_types        | §3.2, §4.3          |
 | vecs                   | §8.1                |

rustlings-macros/info.toml

@@ -187,6 +187,20 @@ There are two solutions:
 1. Add the `return` keyword before `num * num;`
 2. Remove the semicolon `;` after `num * num`"""
 
+[[exercises]]
+name = "functions6"
+dir = "02_functions"
+test = false
+hint = """
+Hint FIX #1: Closures can capture variables defined in the outer context.
+
+Hint FIX #2: Closures can infer both input and returned types, when they are not
+specified in the signature. But the closure cannot be reused with different
+input types.
+
+Read more about closures in the rust book dedicated section:
+https://doc.rust-lang.org/book/ch13-01-closures.html"""
+
 # IF
 
 [[exercises]]
@@ -391,6 +405,18 @@ The first problem is that `get_char` is taking ownership of the string. So
 Once you've fixed that, `string_uppercase`'s function signature will also need
 to be adjusted."""
 
+[[exercises]]
+name = "move_semantics6"
+dir = "06_move_semantics"
+test = false
+hint = """
+When a closure captures a variable to modify it, it actually borrows that variable
+as a mutable reference. In this exercise, the closure mutably borrows the `counter`
+variable, thus, any attempt to borrow `counter` between closure calls leads to an error.
+
+You cannot immutably borrow a variable if a mutable closure is
+called later in the scope."""
+
 # STRUCTS
 
 [[exercises]]

solutions/02_functions/functions6.rs

@@ -0,0 +1,9 @@
+fn main() {
+    let outer_var = 1;
+    let closure_1 = |input_var: u32| -> u32 { input_var + outer_var };
+    println!("Closure#1 returns {}", closure_1(5));
+
+    let closure_2 = |input_var| println!("Closure#2 (input_var {})", input_var);
+    closure_2(2);
+    closure_2(5);
+}

solutions/06_move_semantics/move_semantics6.rs

@@ -0,0 +1,14 @@
+fn main() {
+    let mut counter = 0;
+
+    let mut increment = || {
+        counter += 1;
+        println!("counter equals {}", counter);
+    };
+
+    increment();
+    increment();
+    let _reborrowed_counter = &counter;
+
+    assert_eq!(counter, 2);
+}

src/app_state.rs

@@ -148,11 +148,11 @@ impl AppState {
 
             let mut done_exercises = hash_set_with_capacity(exercises.len());
 
-            for done_exerise_name in lines {
-                if done_exerise_name.is_empty() {
+            for done_exercise_name in lines {
+                if done_exercise_name.is_empty() {
                     break;
                 }
-                done_exercises.insert(done_exerise_name);
+                done_exercises.insert(done_exercise_name);
             }
 
             for (ind, exercise) in exercises.iter_mut().enumerate() {

src/collections.rs

@@ -1,10 +1,9 @@
-use ahash::AHasher;
-use std::hash::BuildHasherDefault;
+use foldhash::fast::FixedState;
 
-/// DOS attacks aren't a concern for Rustlings. Therefore, we use `ahash` with fixed seeds.
-pub type HashSet<T> = std::collections::HashSet<T, BuildHasherDefault<AHasher>>;
+/// DOS attacks aren't a concern for Rustlings. Therefore, we use `foldhash` with a fixed state.
+pub type HashSet<T> = std::collections::HashSet<T, FixedState>;
 
 #[inline]
 pub fn hash_set_with_capacity<T>(capacity: usize) -> HashSet<T> {
-    HashSet::with_capacity_and_hasher(capacity, BuildHasherDefault::<AHasher>::default())
+    HashSet::with_capacity_and_hasher(capacity, FixedState::default())
 }

src/dev/check.rs

@@ -17,6 +17,7 @@ use crate::{
     CURRENT_FORMAT_VERSION,
 };
 
+const MAX_N_EXERCISES: usize = 999;
 const MAX_EXERCISE_NAME_LEN: usize = 32;
 
 // Find a char that isn't allowed in the exercise's `name` or `dir`.
@@ -201,7 +202,7 @@ fn check_exercises_unsolved(
 
     for (exercise_name, handle) in handles {
         let Ok(result) = handle.join() else {
-            bail!("Panic while trying to run the exericse {exercise_name}");
+            bail!("Panic while trying to run the exercise {exercise_name}");
         };
 
         match result {
@@ -299,7 +300,7 @@ fn check_solutions(
     for (exercise_info, handle) in info_file.exercises.iter().zip(handles) {
         let Ok(check_result) = handle.join() else {
             bail!(
-                "Panic while trying to run the solution of the exericse {}",
+                "Panic while trying to run the solution of the exercise {}",
                 exercise_info.name,
             );
         };
@@ -347,6 +348,10 @@ fn check_solutions(
 pub fn check(require_solutions: bool) -> Result<()> {
     let info_file = InfoFile::parse()?;
 
+    if info_file.exercises.len() > MAX_N_EXERCISES {
+        bail!("The maximum number of exercises is {MAX_N_EXERCISES}");
+    }
+
     if cfg!(debug_assertions) {
         // A hack to make `cargo run -- dev check` work when developing Rustlings.
         check_cargo_toml(&info_file.exercises, "dev/Cargo.toml", b"../")?;

src/term.rs

@@ -166,7 +166,7 @@ pub fn progress_bar<'a>(
     total: u16,
     term_width: u16,
 ) -> io::Result<()> {
-    debug_assert!(total < 1000);
+    debug_assert!(total <= 999);
     debug_assert!(progress <= total);
 
     const PREFIX: &[u8] = b"Progress: [";