Add --base-url argument

src/app_state.rs

@@ -21,6 +21,7 @@ use crate::{
     exercise::{Exercise, RunnableExercise},
     info_file::ExerciseInfo,
     term::{self, CheckProgressVisualizer},
+    url_replacer::UrlReplacer,
 };
 
 const STATE_FILE_NAME: &str = ".rustlings-state.txt";
@@ -68,6 +69,7 @@ impl AppState {
     pub fn new(
         exercise_infos: Vec<ExerciseInfo>,
         final_message: String,
+        base_url: Option<String>,
     ) -> Result<(Self, StateFileStatus)> {
         let cmd_runner = CmdRunner::build()?;
         let mut state_file = OpenOptions::new()
@@ -80,6 +82,9 @@ impl AppState {
                 format!("Failed to open or create the state file {STATE_FILE_NAME}")
             })?;
 
+        // replacer for rustbook url
+        let url_replacer = base_url.as_ref().map(|url| UrlReplacer::new(url));
+
         let dir_canonical_path = term::canonicalize("exercises");
         let mut exercises = exercise_infos
             .into_iter()
@@ -90,7 +95,11 @@ impl AppState {
                 let path = exercise_info.path().leak();
                 let name = exercise_info.name.leak();
                 let dir = exercise_info.dir.map(|dir| &*dir.leak());
-                let hint = exercise_info.hint.leak().trim_ascii();
+                let mut hint = exercise_info.hint.leak().trim_ascii();
+
+                if let Some(replacer) = &url_replacer {
+                    hint = replacer.replace(hint).leak();
+                }
 
                 let canonical_path = dir_canonical_path.as_deref().map(|dir_canonical_path| {
                     let mut canonical_path;

src/main.rs

@@ -21,6 +21,7 @@ mod init;
 mod list;
 mod run;
 mod term;
+mod url_replacer;
 mod watch;
 
 const CURRENT_FORMAT_VERSION: u8 = 1;
@@ -35,6 +36,10 @@ struct Args {
     /// Only use this if Rustlings fails to detect exercise file changes.
     #[arg(long)]
     manual_run: bool,
+
+    /// Change rustbook url to passed one.
+    #[arg(long)]
+    base_url: Option<String>,
 }
 
 #[derive(Subcommand)]
@@ -94,6 +99,7 @@ fn main() -> Result<ExitCode> {
     let (mut app_state, state_file_status) = AppState::new(
         info_file.exercises,
         info_file.final_message.unwrap_or_default(),
+        args.base_url,
     )?;
 
     // Show the welcome message if the state file doesn't exist yet.

src/url_replacer.rs

@@ -0,0 +1,67 @@
+pub struct UrlReplacer {
+    base_url: String,
+}
+
+const EN_BASE_URL: &str = "https://doc.rust-lang.org/book";
+
+impl UrlReplacer {
+    /// this fn will trim url end with '/'
+    pub fn new(base_url: &str) -> Self {
+        let url = if base_url.ends_with('/') {
+            base_url.trim_end_matches('/').to_owned()
+        } else {
+            base_url.to_owned()
+        };
+
+        Self { base_url: url }
+    }
+
+    /// replace rustbook url
+    pub fn replace(&self, hint: &str) -> String {
+        hint.replace(EN_BASE_URL, &self.base_url)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    const TEST_DOMAIN: &str = "https://doc.rust-kr.org";
+
+    #[test]
+    fn non_rustbook_url() {
+        let replacer = UrlReplacer::new(&String::from(TEST_DOMAIN));
+
+        let hint = "\
+hints (...) lines (...)
+link: https://example.com/ch03-02-data-types.html";
+
+        assert_eq!(hint, replacer.replace(hint));
+    }
+
+    #[test]
+    fn replace_rustbook_url() {
+        let replacer = UrlReplacer::new(&String::from(TEST_DOMAIN));
+
+        let hint = "\
+hints (...) lines (...)
+link: https://doc.rust-lang.org/book/ch03-02-data-types.html";
+
+        assert_eq!(
+            "\
+hints (...) lines (...)
+link: https://doc.rust-kr.org/ch03-02-data-types.html",
+            replacer.replace(hint)
+        );
+    }
+
+    #[test]
+    fn trim_end_with_slash() {
+        let mut domain = String::from(TEST_DOMAIN);
+        domain.push('/');
+
+        let replacer = UrlReplacer::new(&domain);
+
+        assert_eq!(TEST_DOMAIN, replacer.base_url);
+    }
+}