Allow initialization in a workspace

src/init.rs

@@ -3,30 +3,40 @@ use ratatui::crossterm::style::Stylize;
 use std::{
     env::set_current_dir,
     fs::{self, create_dir},
-    io::ErrorKind,
+    io::{self, Write},
     path::Path,
     process::{Command, Stdio},
 };
 
-use crate::{cargo_toml::updated_cargo_toml, embedded::EMBEDDED_FILES, info_file::InfoFile};
+use crate::{
+    cargo_toml::updated_cargo_toml, embedded::EMBEDDED_FILES, info_file::InfoFile,
+    term::press_enter_prompt,
+};
 
 pub fn init() -> Result<()> {
-    // Prevent initialization in a directory that contains the file `Cargo.toml`.
-    // This can mean that Rustlings was already initialized in this directory.
-    // Otherwise, this can cause problems with Cargo workspaces.
-    if Path::new("Cargo.toml").exists() {
-        bail!(CARGO_TOML_EXISTS_ERR);
-    }
-
-    let rustlings_path = Path::new("rustlings");
-    if let Err(e) = create_dir(rustlings_path) {
-        if e.kind() == ErrorKind::AlreadyExists {
+    let rustlings_dir = Path::new("rustlings");
+    if rustlings_dir.exists() {
         bail!(RUSTLINGS_DIR_ALREADY_EXISTS_ERR);
     }
-        return Err(e.into());
+
+    let mut stdout = io::stdout().lock();
+    let mut init_git = true;
+
+    if Path::new("Cargo.toml").exists() {
+        if Path::new("exercises").exists() && Path::new("solutions").exists() {
+            bail!(IN_INITIALIZED_DIR_ERR);
         }
 
-    set_current_dir("rustlings")
+        stdout.write_all(CARGO_TOML_EXISTS_PROMPT_MSG)?;
+        press_enter_prompt(&mut stdout)?;
+        init_git = false;
+    }
+
+    stdout.write_all(b"This command will create the directory `rustlings/` which will contain the exercises.\nPress ENTER to continue ")?;
+    press_enter_prompt(&mut stdout)?;
+
+    create_dir(rustlings_dir).context("Failed to create the `rustlings/` directory")?;
+    set_current_dir(rustlings_dir)
         .context("Failed to change the current directory to `rustlings/`")?;
 
     let info_file = InfoFile::parse()?;
@@ -75,18 +85,21 @@ pub fn init() -> Result<()> {
     fs::write(".vscode/extensions.json", VS_CODE_EXTENSIONS_JSON)
         .context("Failed to create the file `rustlings/.vscode/extensions.json`")?;
 
+    if init_git {
         // Ignore any Git error because Git initialization is not required.
         let _ = Command::new("git")
             .arg("init")
             .stdin(Stdio::null())
             .stderr(Stdio::null())
             .status();
+    }
 
-    println!(
+    writeln!(
+        stdout,
         "\n{}\n\n{}",
         "Initialization done ✓".green(),
         POST_INIT_MSG.bold(),
-    );
+    )?;
 
     Ok(())
 }
@@ -104,7 +117,7 @@ target/
 
 pub const VS_CODE_EXTENSIONS_JSON: &[u8] = br#"{"recommendations":["rust-lang.rust-analyzer"]}"#;
 
-const CARGO_TOML_EXISTS_ERR: &str = "The current directory contains the file `Cargo.toml`.
+const IN_INITIALIZED_DIR_ERR: &str = "It looks like Rustlings is already initialized in this directory.
 
 If you already initialized Rustlings, run the command `rustlings` for instructions on getting started with the exercises.
 Otherwise, please run `rustlings init` again in another directory.";
@@ -115,5 +128,19 @@ You probably already initialized Rustlings.
 Run `cd rustlings`
 Then run `rustlings` again";
 
+const CARGO_TOML_EXISTS_PROMPT_MSG: &[u8] = br#"You are about to initialize Rustlings in a directory that already contains a `Cargo.toml` file!
+
+  => It is recommended to abort with CTRL+C and initialize Rustlings in another directory <=
+
+If you know what you are doing and want to initialize Rustlings in a Cargo workspace,
+then you need to add its directory to `members` in the `workspace` section of the `Cargo.toml` file:
+
+```toml
+[workspace]
+members = ["rustlings"]
+```
+
+Press ENTER if you are sure that you want to continue after reading the warning above "#;
+
 const POST_INIT_MSG: &str = "Run `cd rustlings` to go into the generated directory.
 Then run `rustlings` to get started.";

src/main.rs

@@ -2,10 +2,11 @@ use anyhow::{bail, Context, Result};
 use app_state::StateFileStatus;
 use clap::{Parser, Subcommand};
 use std::{
-    io::{self, BufRead, IsTerminal, StdoutLock, Write},
+    io::{self, IsTerminal, Write},
     path::Path,
     process::exit,
 };
+use term::{clear_terminal, press_enter_prompt};
 
 use self::{app_state::AppState, dev::DevCommands, info_file::InfoFile, watch::WatchExit};
 
@@ -20,20 +21,12 @@ mod init;
 mod list;
 mod progress_bar;
 mod run;
+mod term;
 mod terminal_link;
 mod watch;
 
 const CURRENT_FORMAT_VERSION: u8 = 1;
 
-fn clear_terminal(stdout: &mut StdoutLock) -> io::Result<()> {
-    stdout.write_all(b"\x1b[H\x1b[2J\x1b[3J")
-}
-
-fn press_enter_prompt() -> io::Result<()> {
-    io::stdin().lock().read_until(b'\n', &mut Vec::new())?;
-    Ok(())
-}
-
 /// Rustlings is a collection of small exercises to get you used to writing and reading Rust code
 #[derive(Parser)]
 #[command(version)]
@@ -79,14 +72,6 @@ fn main() -> Result<()> {
 
     match args.command {
         Some(Subcommands::Init) => {
-            {
-                let mut stdout = io::stdout().lock();
-                stdout.write_all(b"This command will create the directory `rustlings/` which will contain the exercises.\nPress ENTER to continue ")?;
-                stdout.flush()?;
-                press_enter_prompt()?;
-                stdout.write_all(b"\n")?;
-            }
-
             return init::init().context("Initialization failed");
         }
         Some(Subcommands::Dev(dev_command)) => return dev_command.run(),
@@ -118,8 +103,7 @@ fn main() -> Result<()> {
 
                 let welcome_message = welcome_message.trim_ascii();
                 write!(stdout, "{welcome_message}\n\nPress ENTER to continue ")?;
-                stdout.flush()?;
-                press_enter_prompt()?;
+                press_enter_prompt(&mut stdout)?;
                 clear_terminal(&mut stdout)?;
                 // Flush to be able to show errors occuring before printing a newline to stdout.
                 stdout.flush()?;

src/term.rs

@@ -0,0 +1,12 @@
+use std::io::{self, BufRead, StdoutLock, Write};
+
+pub fn clear_terminal(stdout: &mut StdoutLock) -> io::Result<()> {
+    stdout.write_all(b"\x1b[H\x1b[2J\x1b[3J")
+}
+
+pub fn press_enter_prompt(stdout: &mut StdoutLock) -> io::Result<()> {
+    stdout.flush()?;
+    io::stdin().lock().read_until(b'\n', &mut Vec::new())?;
+    stdout.write_all(b"\n")?;
+    Ok(())
+}