Canonicalize exercise paths only once

6 files changed, 77 insertions, 29 deletions

diff --git a/src/app_state.rs b/src/app_state.rs
index 381aaf8..7123d11 100644
--- a/src/app_state.rs
+++ b/src/app_state.rs
@@ -3,7 +3,7 @@ use std::{
     env,
     fs::{File, OpenOptions},
     io::{self, Read, Seek, StdoutLock, Write},
-    path::Path,
+    path::{Path, MAIN_SEPARATOR_STR},
     process::{Command, Stdio},
     thread,
 };
@@ -15,6 +15,7 @@ use crate::{
     embedded::EMBEDDED_FILES,
     exercise::{Exercise, RunnableExercise},
     info_file::ExerciseInfo,
+    term,
 };
 
 const STATE_FILE_NAME: &str = ".rustlings-state.txt";
@@ -71,6 +72,7 @@ impl AppState {
                 format!("Failed to open or create the state file {STATE_FILE_NAME}")
             })?;
 
+        let dir_canonical_path = term::canonicalize("exercises");
         let mut exercises = exercise_infos
             .into_iter()
             .map(|exercise_info| {
@@ -82,10 +84,32 @@ impl AppState {
                 let dir = exercise_info.dir.map(|dir| &*dir.leak());
                 let hint = exercise_info.hint.leak().trim_ascii();
 
+                let canonical_path = dir_canonical_path.as_deref().map(|dir_canonical_path| {
+                    let mut canonical_path;
+                    if let Some(dir) = dir {
+                        canonical_path = String::with_capacity(
+                            2 + dir_canonical_path.len() + dir.len() + name.len(),
+                        );
+                        canonical_path.push_str(dir_canonical_path);
+                        canonical_path.push_str(MAIN_SEPARATOR_STR);
+                        canonical_path.push_str(dir);
+                    } else {
+                        canonical_path =
+                            String::with_capacity(1 + dir_canonical_path.len() + name.len());
+                        canonical_path.push_str(dir_canonical_path);
+                    }
+
+                    canonical_path.push_str(MAIN_SEPARATOR_STR);
+                    canonical_path.push_str(name);
+                    canonical_path.push_str(".rs");
+                    canonical_path
+                });
+
                 Exercise {
                     dir,
                     name,
                     path,
+                    canonical_path,
                     test: exercise_info.test,
                     strict_clippy: exercise_info.strict_clippy,
                     hint,
@@ -486,6 +510,7 @@ mod tests {
             dir: None,
             name: "0",
             path: "exercises/0.rs",
+            canonical_path: None,
             test: false,
             strict_clippy: false,
             hint: "",
diff --git a/src/exercise.rs b/src/exercise.rs
index 11eea63..7fb2343 100644
--- a/src/exercise.rs
+++ b/src/exercise.rs
@@ -7,7 +7,7 @@ use std::io::{self, StdoutLock, Write};
 
 use crate::{
     cmd::CmdRunner,
-    term::{terminal_file_link, write_ansi},
+    term::{self, terminal_file_link, write_ansi, CountedWrite},
 };
 
 /// The initial capacity of the output buffer.
@@ -18,7 +18,11 @@ pub fn solution_link_line(stdout: &mut StdoutLock, solution_path: &str) -> io::R
     stdout.write_all(b"Solution")?;
     stdout.queue(ResetColor)?;
     stdout.write_all(b" for comparison: ")?;
-    terminal_file_link(stdout, solution_path, Color::Cyan)?;
+    if let Some(canonical_path) = term::canonicalize(solution_path) {
+        terminal_file_link(stdout, solution_path, &canonical_path, Color::Cyan)?;
+    } else {
+        stdout.write_all(solution_path.as_bytes())?;
+    }
     stdout.write_all(b"\n")
 }
 
@@ -60,12 +64,23 @@ pub struct Exercise {
     pub name: &'static str,
     /// Path of the exercise file starting with the `exercises/` directory.
     pub path: &'static str,
+    pub canonical_path: Option<String>,
     pub test: bool,
     pub strict_clippy: bool,
     pub hint: &'static str,
     pub done: bool,
 }
 
+impl Exercise {
+    pub fn terminal_file_link<'a>(&self, writer: &mut impl CountedWrite<'a>) -> io::Result<()> {
+        if let Some(canonical_path) = self.canonical_path.as_deref() {
+            return terminal_file_link(writer, self.path, canonical_path, Color::Blue);
+        }
+
+        writer.write_str(self.path)
+    }
+}
+
 pub trait RunnableExercise {
     fn name(&self) -> &str;
     fn dir(&self) -> Option<&str>;
diff --git a/src/list/state.rs b/src/list/state.rs
index 468049a..ed7c71f 100644
--- a/src/list/state.rs
+++ b/src/list/state.rs
@@ -13,7 +13,7 @@ use std::{
 use crate::{
     app_state::AppState,
     exercise::Exercise,
-    term::{progress_bar, terminal_file_link, CountedWrite, MaxLenWriter},
+    term::{progress_bar, CountedWrite, MaxLenWriter},
 };
 
 use super::scroll_state::ScrollState;
@@ -158,7 +158,7 @@ impl<'a> ListState<'a> {
             if self.app_state.vs_code() {
                 writer.write_str(exercise.path)?;
             } else {
-                terminal_file_link(&mut writer, exercise.path, Color::Blue)?;
+                exercise.terminal_file_link(&mut writer)?;
             }
 
             next_ln(stdout)?;
diff --git a/src/run.rs b/src/run.rs
index 929b475..f0faa69 100644
--- a/src/run.rs
+++ b/src/run.rs
@@ -11,7 +11,6 @@ use std::{
 use crate::{
     app_state::{AppState, ExercisesProgress},
     exercise::{solution_link_line, RunnableExercise, OUTPUT_CAPACITY},
-    term::terminal_file_link,
 };
 
 pub fn run(app_state: &mut AppState) -> Result<()> {
@@ -26,7 +25,9 @@ pub fn run(app_state: &mut AppState) -> Result<()> {
         app_state.set_pending(app_state.current_exercise_ind())?;
 
         stdout.write_all(b"Ran ")?;
-        terminal_file_link(&mut stdout, app_state.current_exercise().path, Color::Blue)?;
+        app_state
+            .current_exercise()
+            .terminal_file_link(&mut stdout)?;
         stdout.write_all(b" with errors\n")?;
         exit(1);
     }
@@ -46,7 +47,9 @@ pub fn run(app_state: &mut AppState) -> Result<()> {
     match app_state.done_current_exercise(&mut stdout)? {
         ExercisesProgress::CurrentPending | ExercisesProgress::NewPending => {
             stdout.write_all(b"Next exercise: ")?;
-            terminal_file_link(&mut stdout, app_state.current_exercise().path, Color::Blue)?;
+            app_state
+                .current_exercise()
+                .terminal_file_link(&mut stdout)?;
             stdout.write_all(b"\n")?;
         }
         ExercisesProgress::AllDone => (),
diff --git a/src/term.rs b/src/term.rs
index 489d658..5b557ec 100644
--- a/src/term.rs
+++ b/src/term.rs
@@ -1,14 +1,13 @@
-use std::{
-    fmt, fs,
-    io::{self, BufRead, StdoutLock, Write},
-};
-
 use crossterm::{
     cursor::MoveTo,
     style::{Attribute, Color, SetAttribute, SetForegroundColor},
     terminal::{Clear, ClearType},
     Command, QueueableCommand,
 };
+use std::{
+    fmt, fs,
+    io::{self, BufRead, StdoutLock, Write},
+};
 
 pub struct MaxLenWriter<'a, 'b> {
     pub stdout: &'a mut StdoutLock<'b>,
@@ -151,25 +150,29 @@ pub fn press_enter_prompt(stdout: &mut StdoutLock) -> io::Result<()> {
     stdout.write_all(b"\n")
 }
 
+/// Canonicalize, convert to string and remove verbatim part on Windows.
+pub fn canonicalize(path: &str) -> Option<String> {
+    fs::canonicalize(path)
+        .ok()?
+        .into_os_string()
+        .into_string()
+        .ok()
+        .map(|mut path| {
+            // Windows itself can't handle its verbatim paths.
+            if cfg!(windows) && path.as_bytes().starts_with(br"\\?\") {
+                path.drain(..4);
+            }
+
+            path
+        })
+}
+
 pub fn terminal_file_link<'a>(
     writer: &mut impl CountedWrite<'a>,
     path: &str,
+    canonical_path: &str,
     color: Color,
 ) -> io::Result<()> {
-    let canonical_path = fs::canonicalize(path).ok();
-
-    let Some(canonical_path) = canonical_path.as_deref().and_then(|p| p.to_str()) else {
-        return writer.write_str(path);
-    };
-
-    // Windows itself can't handle its verbatim paths.
-    #[cfg(windows)]
-    let canonical_path = if canonical_path.len() > 5 && &canonical_path[0..4] == r"\\?\" {
-        &canonical_path[4..]
-    } else {
-        canonical_path
-    };
-
     writer
         .stdout()
         .queue(SetForegroundColor(color))?
diff --git a/src/watch/state.rs b/src/watch/state.rs
index 1c2e2a9..fe9e274 100644
--- a/src/watch/state.rs
+++ b/src/watch/state.rs
@@ -11,7 +11,7 @@ use crate::{
     app_state::{AppState, ExercisesProgress},
     clear_terminal,
     exercise::{solution_link_line, RunnableExercise, OUTPUT_CAPACITY},
-    term::{progress_bar, terminal_file_link},
+    term::progress_bar,
 };
 
 #[derive(PartialEq, Eq)]
@@ -184,7 +184,9 @@ impl<'a> WatchState<'a> {
         )?;
 
         stdout.write_all(b"\nCurrent exercise: ")?;
-        terminal_file_link(stdout, self.app_state.current_exercise().path, Color::Blue)?;
+        self.app_state
+            .current_exercise()
+            .terminal_file_link(stdout)?;
         stdout.write_all(b"\n\n")?;
 
         self.show_prompt(stdout)?;