Merge branch 'master' of https://github.com/rust-lang/rustlings

README.md

@@ -43,7 +43,7 @@ Set-ExecutionPolicy RemoteSigned
 Then, you can run:
 
 ```ps
-Invoke-WebRequest https://git.io/rustlings-win | Select-Object -ExpandProperty Content | Out-File $env:TMP/install_rustlings.ps1; Unblock-File $env:TMP/install_rustlings.ps1; Invoke-Expression $env:TMP/install_rustlings.ps1
+Start-BitsTransfer -Source https://git.io/rustlings-win -Destination $env:TMP/install_rustlings.ps1; Unblock-File $env:TMP/install_rustlings.ps1; Invoke-Expression $env:TMP/install_rustlings.ps1
 ```
 
 To install Rustlings. Same as on MacOS/Linux, you will have access to the `rustlings` command after it.

exercises/conversions/as_ref_mut.rs

@@ -36,4 +36,16 @@ mod tests {
         let s = "Cafe au lait";
         assert_eq!(char_counter(s), byte_counter(s));
     }
+
+    #[test]
+    fn different_counts_using_string() {
+        let s = String::from("Café au lait");
+        assert_ne!(char_counter(s.clone()), byte_counter(s));
+    }
+
+    #[test]
+    fn same_counts_using_string() {
+        let s = String::from("Cafe au lait");
+        assert_eq!(char_counter(s.clone()), byte_counter(s));
+    }
 }

exercises/structs/structs3.rs

@@ -5,17 +5,18 @@
 
 #[derive(Debug)]
 struct Package {
-    from: String,
-    to: String,
-    weight: f32
+    sender_country: String,
+    recipient_country: String,
+    weight_in_grams: i32,
 }
 
 impl Package {
-    fn new(from: String, to: String, weight: f32) -> Package {
-        if weight <= 0.0 {
+    fn new(sender_country: String, recipient_country: String, weight_in_grams: i32) -> Package {
+        if weight_in_grams <= 0 {
+            // Something goes here...
             panic!("Package is lighter then air!")
         } else {
-            return Package {from, to, weight};
+            return Package {sender_country, recipient_country, weight_in_grams};
         }
     }
 
@@ -24,8 +25,8 @@ impl Package {
         self.from != self.to
     }
 
-    fn get_fees(&self, cost_per_kg: f32) -> f32 {
-        // Something goes here...
+    fn get_fees(&self, cents_per_kg: i32) -> i32 {
+        // Something goes here... (beware of grams to kg conversion)
         self.weight * cost_per_kg
     }
 }
@@ -37,31 +38,31 @@ mod tests {
     #[test]
     #[should_panic]
     fn fail_creating_weightless_package() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Austria");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Austria");
 
-        Package::new(country_from, country_to, -2.21);
+        Package::new(sender_country, recipient_country, -2210);
     }
 
     #[test]
     fn create_international_package() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Russia");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Russia");
         
-        let package = Package::new(country_from, country_to, 1.2);
+        let package = Package::new(sender_country, recipient_country, 1200);
 
         assert!(package.is_international());
     }
 
     #[test]
     fn calculate_transport_fees() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Spain");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Spain");
 
-        let country_fee = 8.0;
+        let cents_per_kg = 8.0;
         
-        let package = Package::new(country_from, country_to, 22.0);
+        let package = Package::new(sender_country, recipient_country, 1500);
         
-        assert_eq!(package.get_fees(country_fee), 176.0);
+        assert_eq!(package.get_fees(cents_per_kg), 4500);
     }
 }

info.toml

@@ -724,8 +724,10 @@ name = "generics2"
 path = "exercises/generics/generics2.rs"
 mode = "test"
 hint = """
-Think carefully about what we need to do here. Currently we are wrapping only values of
-type 'u32'. Maybe we need to update the explicit references to this data type somehow?
+Currently we are wrapping only values of type 'u32'. 
+Maybe we could update the explicit references to this data type somehow?
+
+If you are still stuck https://doc.rust-lang.org/stable/book/ch10-01-syntax.html#in-method-definitions
 """
 
 [[exercises]]
@@ -802,7 +804,7 @@ name = "try_from_into"
 path = "exercises/conversions/try_from_into.rs"
 mode = "test"
 hint = """
-Follow the steps provided right before the `From` implementation.
+Follow the steps provided right before the `TryFrom` implementation.
 You can also use the example at https://doc.rust-lang.org/std/convert/trait.TryFrom.html"""
 
 [[exercises]]
@@ -819,4 +821,4 @@ mode = "test"
 hint = """
 The implementation of FromStr should return an Ok with a Person object,
 or an Err with a string if the string is not valid.
-This is a some like an `try_from_into` exercise."""
+This is almost like the `try_from_into` exercise."""

install.sh

@@ -102,12 +102,30 @@ Path=${1:-rustlings/}
 echo "Cloning Rustlings at $Path..."
 git clone -q https://github.com/rust-lang/rustlings $Path
 
+cd $Path
+
 Version=$(curl -s https://api.github.com/repos/rust-lang/rustlings/releases/latest | ${PY} -c "import json,sys;obj=json.load(sys.stdin);print(obj['tag_name']);")
 CargoBin="${CARGO_HOME:-$HOME/.cargo}/bin"
 
+if [[ -z ${Version} ]]
+then
+    echo "The latest tag version could not be fetched remotely."
+    echo "Using the local git repository..."
+    Version=$(ls -tr .git/refs/tags/ | tail -1)
+    if [[ -z ${Version}  ]]
+    then
+        echo "No valid tag version found"
+        echo "Rustlings will be installed using the master branch"
+        Version="master"
+    else
+        Version="tags/${Version}"
+    fi
+else
+    Version="tags/${Version}"
+fi
+
 echo "Checking out version $Version..."
-cd $Path
-git checkout -q tags/$Version
+git checkout -q ${Version}
 
 echo "Installing the 'rustlings' executable..."
 cargo install --force --path .

src/exercise.rs

@@ -11,15 +11,21 @@ const I_AM_DONE_REGEX: &str = r"(?m)^\s*///?\s*I\s+AM\s+NOT\s+DONE";
 const CONTEXT: usize = 2;
 const CLIPPY_CARGO_TOML_PATH: &str = "./exercises/clippy/Cargo.toml";
 
+// Get a temporary file name that is hopefully unique to this process
+#[inline]
 fn temp_file() -> String {
     format!("./temp_{}", process::id())
 }
 
+// The mode of the exercise.
 #[derive(Deserialize, Copy, Clone)]
 #[serde(rename_all = "lowercase")]
 pub enum Mode {
+    // Indicates that the exercise should be compiled as a binary
     Compile,
+    // Indicates that the exercise should be compiled as a test harness
     Test,
+    // Indicates that the exercise should be linted with clippy
     Clippy,
 }
 
@@ -28,41 +34,60 @@ pub struct ExerciseList {
     pub exercises: Vec<Exercise>,
 }
 
+// A representation of a rustlings exercise.
+// This is deserialized from the accompanying info.toml file
 #[derive(Deserialize)]
 pub struct Exercise {
+    // Name of the exercise
     pub name: String,
+    // The path to the file containing the exercise's source code
     pub path: PathBuf,
+    // The mode of the exercise (Test, Compile, or Clippy)
     pub mode: Mode,
+    // The hint text associated with the exercise
     pub hint: String,
 }
 
+// An enum to track of the state of an Exercise.
+// An Exercise can be either Done or Pending
 #[derive(PartialEq, Debug)]
 pub enum State {
+    // The state of the exercise once it's been completed
     Done,
+    // The state of the exercise while it's not completed yet
     Pending(Vec<ContextLine>),
 }
 
+// The context information of a pending exercise
 #[derive(PartialEq, Debug)]
 pub struct ContextLine {
+    // The source code that is still pending completion
     pub line: String,
+    // The line number of the source code still pending completion
     pub number: usize,
+    // Whether or not this is important
     pub important: bool,
 }
 
+// The result of compiling an exercise
 pub struct CompiledExercise<'a> {
     exercise: &'a Exercise,
     _handle: FileHandle,
 }
 
 impl<'a> CompiledExercise<'a> {
+    // Run the compiled exercise
     pub fn run(&self) -> Result<ExerciseOutput, ExerciseOutput> {
         self.exercise.run()
     }
 }
 
+// A representation of an already executed binary
 #[derive(Debug)]
 pub struct ExerciseOutput {
+    // The textual contents of the standard output of the binary
     pub stdout: String,
+    // The textual contents of the standard error of the binary
     pub stderr: String,
 }
 
@@ -140,7 +165,11 @@ path = "{}.rs""#,
     }
 
     fn run(&self) -> Result<ExerciseOutput, ExerciseOutput> {
-        let cmd = Command::new(&temp_file())
+        let arg = match self.mode {
+            Mode::Test => "--show-output",
+            _ => ""
+        };
+        let cmd = Command::new(&temp_file()).arg(arg)
             .output()
             .expect("Failed to run 'run' command");
 
@@ -205,6 +234,7 @@ impl Display for Exercise {
     }
 }
 
+#[inline]
 fn clean() {
     let _ignored = remove_file(&temp_file());
 }
@@ -280,4 +310,16 @@ mod test {
 
         assert_eq!(exercise.state(), State::Done);
     }
+
+    #[test]
+    fn test_exercise_with_output() {
+        let exercise = Exercise {
+            name: "finished_exercise".into(),
+            path: PathBuf::from("tests/fixture/success/testSuccess.rs"),
+            mode: Mode::Test,
+            hint: String::new(),
+        };
+        let out = exercise.compile().unwrap().run().unwrap();
+        assert!(out.stdout.contains("THIS TEST TOO SHALL PASS"));
+    }
 }

src/main.rs

@@ -27,8 +27,21 @@ fn main() {
         .version(crate_version!())
         .author("Olivia Hugger, Carol Nichols")
         .about("Rustlings is a collection of small exercises to get you used to writing and reading Rust code")
-        .subcommand(SubCommand::with_name("verify").alias("v").about("Verifies all exercises according to the recommended order"))
-        .subcommand(SubCommand::with_name("watch").alias("w").about("Reruns `verify` when files were edited"))
+        .arg(
+            Arg::with_name("nocapture")
+                .long("nocapture")
+                .help("Show outputs from the test exercises")
+        )
+        .subcommand(
+            SubCommand::with_name("verify")
+                .alias("v")
+                .about("Verifies all exercises according to the recommended order")
+        )
+        .subcommand(
+            SubCommand::with_name("watch")
+                .alias("w")
+                .about("Reruns `verify` when files were edited")
+        )
         .subcommand(
             SubCommand::with_name("run")
                 .alias("r")
@@ -43,7 +56,7 @@ fn main() {
         )
         .get_matches();
 
-    if None == matches.subcommand_name() {
+    if matches.subcommand_name().is_none() {
         println!();
         println!(r#"       welcome to...                      "#);
         println!(r#"                 _   _ _                  "#);
@@ -73,6 +86,7 @@ fn main() {
 
     let toml_str = &fs::read_to_string("info.toml").unwrap();
     let exercises = toml::from_str::<ExerciseList>(toml_str).unwrap().exercises;
+    let verbose = matches.is_present("nocapture");
 
     if let Some(ref matches) = matches.subcommand_matches("run") {
         let name = matches.value_of("name").unwrap();
@@ -84,7 +98,7 @@ fn main() {
             std::process::exit(1)
         });
 
-        run(&exercise).unwrap_or_else(|_| std::process::exit(1));
+        run(&exercise, verbose).unwrap_or_else(|_| std::process::exit(1));
     }
 
     if let Some(ref matches) = matches.subcommand_matches("hint") {
@@ -102,25 +116,23 @@ fn main() {
     }
 
     if matches.subcommand_matches("verify").is_some() {
-        verify(&exercises).unwrap_or_else(|_| std::process::exit(1));
+        verify(&exercises, verbose).unwrap_or_else(|_| std::process::exit(1));
     }
 
-    if matches.subcommand_matches("watch").is_some() {
-        if watch(&exercises).is_ok() {
-            println!(
-                "{emoji} All exercises completed! {emoji}",
-                emoji = Emoji("🎉", "★")
-            );
-            println!("");
-            println!("We hope you enjoyed learning about the various aspects of Rust!");
-            println!(
-                "If you noticed any issues, please don't hesitate to report them to our repo."
-            );
-            println!("You can also contribute your own exercises to help the greater community!");
-            println!("");
-            println!("Before reporting an issue or contributing, please read our guidelines:");
-            println!("https://github.com/rust-lang/rustlings/blob/master/CONTRIBUTING.md");
-        }
+    if matches.subcommand_matches("watch").is_some() && watch(&exercises, verbose).is_ok() {
+        println!(
+            "{emoji} All exercises completed! {emoji}",
+            emoji = Emoji("🎉", "★")
+        );
+        println!();
+        println!("We hope you enjoyed learning about the various aspects of Rust!");
+        println!(
+            "If you noticed any issues, please don't hesitate to report them to our repo."
+        );
+        println!("You can also contribute your own exercises to help the greater community!");
+        println!();
+        println!("Before reporting an issue or contributing, please read our guidelines:");
+        println!("https://github.com/rust-lang/rustlings/blob/master/CONTRIBUTING.md");
     }
 
     if matches.subcommand_name().is_none() {
@@ -149,7 +161,7 @@ fn spawn_watch_shell(failed_exercise_hint: &Arc<Mutex<Option<String>>>) {
     });
 }
 
-fn watch(exercises: &[Exercise]) -> notify::Result<()> {
+fn watch(exercises: &[Exercise], verbose: bool) -> notify::Result<()> {
     /* Clears the terminal with an ANSI escape code.
     Works in UNIX and newer Windows terminals. */
     fn clear_screen() {
@@ -164,7 +176,7 @@ fn watch(exercises: &[Exercise]) -> notify::Result<()> {
     clear_screen();
 
     let to_owned_hint = |t: &Exercise| t.hint.to_owned();
-    let failed_exercise_hint = match verify(exercises.iter()) {
+    let failed_exercise_hint = match verify(exercises.iter(), verbose) {
         Ok(_) => return Ok(()),
         Err(exercise) => Arc::new(Mutex::new(Some(to_owned_hint(exercise)))),
     };
@@ -179,7 +191,7 @@ fn watch(exercises: &[Exercise]) -> notify::Result<()> {
                             .iter()
                             .skip_while(|e| !filepath.ends_with(&e.path));
                         clear_screen();
-                        match verify(pending_exercises) {
+                        match verify(pending_exercises, verbose) {
                             Ok(_) => return Ok(()),
                             Err(exercise) => {
                                 let mut failed_exercise_hint = failed_exercise_hint.lock().unwrap();

src/run.rs

@@ -2,15 +2,22 @@ use crate::exercise::{Exercise, Mode};
 use crate::verify::test;
 use indicatif::ProgressBar;
 
-pub fn run(exercise: &Exercise) -> Result<(), ()> {
+// Invoke the rust compiler on the path of the given exercise,
+// and run the ensuing binary.
+// The verbose argument helps determine whether or not to show
+// the output from the test harnesses (if the mode of the exercise is test)
+pub fn run(exercise: &Exercise, verbose: bool) -> Result<(), ()> {
     match exercise.mode {
-        Mode::Test => test(exercise)?,
+        Mode::Test => test(exercise, verbose)?,
         Mode::Compile => compile_and_run(exercise)?,
         Mode::Clippy => compile_and_run(exercise)?,
     }
     Ok(())
 }
 
+// Invoke the rust compiler on the path of the given exercise
+// and run the ensuing binary.
+// This is strictly for non-test binaries, so output is displayed
 fn compile_and_run(exercise: &Exercise) -> Result<(), ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Compiling {}...", exercise).as_str());

src/verify.rs

@@ -2,10 +2,18 @@ use crate::exercise::{CompiledExercise, Exercise, Mode, State};
 use console::style;
 use indicatif::ProgressBar;
 
-pub fn verify<'a>(start_at: impl IntoIterator<Item = &'a Exercise>) -> Result<(), &'a Exercise> {
+// Verify that the provided container of Exercise objects
+// can be compiled and run without any failures.
+// Any such failures will be reported to the end user.
+// If the Exercise being verified is a test, the verbose boolean
+// determines whether or not the test harness outputs are displayed.
+pub fn verify<'a>(
+    start_at: impl IntoIterator<Item = &'a Exercise>,
+    verbose: bool
+) -> Result<(), &'a Exercise> {
     for exercise in start_at {
         let compile_result = match exercise.mode {
-            Mode::Test => compile_and_test(&exercise, RunMode::Interactive),
+            Mode::Test => compile_and_test(&exercise, RunMode::Interactive, verbose),
             Mode::Compile => compile_and_run_interactively(&exercise),
             Mode::Clippy => compile_only(&exercise),
         };
@@ -21,11 +29,13 @@ enum RunMode {
     NonInteractive,
 }
 
-pub fn test(exercise: &Exercise) -> Result<(), ()> {
-    compile_and_test(exercise, RunMode::NonInteractive)?;
+// Compile and run the resulting test harness of the given Exercise
+pub fn test(exercise: &Exercise, verbose: bool) -> Result<(), ()> {
+    compile_and_test(exercise, RunMode::NonInteractive, verbose)?;
     Ok(())
 }
 
+// Invoke the rust compiler without running the resulting binary
 fn compile_only(exercise: &Exercise) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Compiling {}...", exercise).as_str());
@@ -38,6 +48,7 @@ fn compile_only(exercise: &Exercise) -> Result<bool, ()> {
     Ok(prompt_for_completion(&exercise, None))
 }
 
+// Compile the given Exercise and run the resulting binary in an interactive mode
 fn compile_and_run_interactively(exercise: &Exercise) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Compiling {}...", exercise).as_str());
@@ -54,6 +65,7 @@ fn compile_and_run_interactively(exercise: &Exercise) -> Result<bool, ()> {
         Err(output) => {
             warn!("Ran {} with errors", exercise);
             println!("{}", output.stdout);
+            println!("{}", output.stderr);
             return Err(());
         }
     };
@@ -63,7 +75,11 @@ fn compile_and_run_interactively(exercise: &Exercise) -> Result<bool, ()> {
     Ok(prompt_for_completion(&exercise, Some(output.stdout)))
 }
 
-fn compile_and_test(exercise: &Exercise, run_mode: RunMode) -> Result<bool, ()> {
+// Compile the given Exercise as a test harness and display
+// the output if verbose is set to true
+fn compile_and_test(
+    exercise: &Exercise, run_mode: RunMode, verbose: bool
+) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Testing {}...", exercise).as_str());
     progress_bar.enable_steady_tick(100);
@@ -73,7 +89,10 @@ fn compile_and_test(exercise: &Exercise, run_mode: RunMode) -> Result<bool, ()>
     progress_bar.finish_and_clear();
 
     match result {
-        Ok(_) => {
+        Ok(output) => {
+            if verbose {
+                println!("{}", output.stdout);
+            }
             success!("Successfully tested {}", &exercise);
             if let RunMode::Interactive = run_mode {
                 Ok(prompt_for_completion(&exercise, None))
@@ -92,6 +111,8 @@ fn compile_and_test(exercise: &Exercise, run_mode: RunMode) -> Result<bool, ()>
     }
 }
 
+// Compile the given Exercise and return an object with information
+// about the state of the compilation
 fn compile<'a, 'b>(
     exercise: &'a Exercise,
     progress_bar: &'b ProgressBar,
@@ -124,16 +145,16 @@ fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>) ->
         Mode::Clippy => "The code is compiling, and 📎 Clippy 📎 is happy!",
     };
 
-    println!("");
+    println!();
     println!("🎉 🎉  {} 🎉 🎉", success_msg);
-    println!("");
+    println!();
 
     if let Some(output) = prompt_output {
         println!("Output:");
         println!("{}", separator());
         println!("{}", output);
         println!("{}", separator());
-        println!("");
+        println!();
     }
 
     println!("You can keep working on this exercise,");
@@ -141,12 +162,12 @@ fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>) ->
         "or jump into the next one by removing the {} comment:",
         style("`I AM NOT DONE`").bold()
     );
-    println!("");
+    println!();
     for context_line in context {
         let formatted_line = if context_line.important {
             format!("{}", style(context_line.line).bold())
         } else {
-            format!("{}", context_line.line)
+            context_line.line.to_string()
         };
 
         println!(

tests/fixture/success/testSuccess.rs

@@ -1,4 +1,5 @@
 #[test]
 fn passing() {
+    println!("THIS TEST TOO SHALL PASS");
     assert!(true);
 }

tests/integration_tests.rs

@@ -159,3 +159,25 @@ fn run_test_exercise_does_not_prompt() {
         .code(0)
         .stdout(predicates::str::contains("I AM NOT DONE").not());
 }
+
+#[test]
+fn run_single_test_success_with_output() {
+    Command::cargo_bin("rustlings")
+        .unwrap()
+        .args(&["--nocapture", "r", "testSuccess"])
+        .current_dir("tests/fixture/success/")
+        .assert()
+        .code(0)
+        .stdout(predicates::str::contains("THIS TEST TOO SHALL PAS"));
+}
+
+#[test]
+fn run_single_test_success_without_output() {
+    Command::cargo_bin("rustlings")
+        .unwrap()
+        .args(&["r", "testSuccess"])
+        .current_dir("tests/fixture/success/")
+        .assert()
+        .code(0)
+        .stdout(predicates::str::contains("THIS TEST TOO SHALL PAS").not());
+}