rustlings/src/app_state.rs
2024-04-27 17:31:51 +02:00

443 lines
14 KiB
Rust

use anyhow::{bail, Context, Result};
use crossterm::{
style::Stylize,
terminal::{Clear, ClearType},
ExecutableCommand,
};
use serde::Deserialize;
use std::{
fs::{self, File},
io::{Read, StdoutLock, Write},
path::{Path, PathBuf},
process::{Command, Stdio},
};
use crate::{
embedded::EMBEDDED_FILES,
exercise::{Exercise, OUTPUT_CAPACITY},
info_file::ExerciseInfo,
DEBUG_PROFILE,
};
const STATE_FILE_NAME: &str = ".rustlings-state.txt";
const BAD_INDEX_ERR: &str = "The current exercise index is higher than the number of exercises";
#[must_use]
pub enum ExercisesProgress {
AllDone,
Pending,
}
pub enum StateFileStatus {
Read,
NotRead,
}
#[derive(Deserialize)]
struct CargoMetadata {
target_directory: PathBuf,
}
pub struct AppState {
current_exercise_ind: usize,
exercises: Vec<Exercise>,
n_done: u16,
final_message: String,
file_buf: Vec<u8>,
official_exercises: bool,
target_dir: PathBuf,
}
impl AppState {
fn update_from_file(&mut self) -> StateFileStatus {
self.file_buf.clear();
self.n_done = 0;
if File::open(STATE_FILE_NAME)
.and_then(|mut file| file.read_to_end(&mut self.file_buf))
.is_err()
{
return StateFileStatus::NotRead;
}
// See `Self::write` for more information about the file format.
let mut lines = self.file_buf.split(|c| *c == b'\n').skip(2);
let Some(current_exercise_name) = lines.next() else {
return StateFileStatus::NotRead;
};
if current_exercise_name.is_empty() || lines.next().is_none() {
return StateFileStatus::NotRead;
}
let mut done_exercises = hashbrown::HashSet::with_capacity(self.exercises.len());
for done_exerise_name in lines {
if done_exerise_name.is_empty() {
break;
}
done_exercises.insert(done_exerise_name);
}
for (ind, exercise) in self.exercises.iter_mut().enumerate() {
if done_exercises.contains(exercise.name.as_bytes()) {
exercise.done = true;
self.n_done += 1;
}
if exercise.name.as_bytes() == current_exercise_name {
self.current_exercise_ind = ind;
}
}
StateFileStatus::Read
}
pub fn new(
exercise_infos: Vec<ExerciseInfo>,
final_message: String,
) -> Result<(Self, StateFileStatus)> {
let metadata_output = Command::new("cargo")
.arg("metadata")
.arg("-q")
.arg("--format-version")
.arg("1")
.arg("--no-deps")
.stdin(Stdio::null())
.stderr(Stdio::inherit())
.output()
.context(CARGO_METADATA_ERR)?
.stdout;
let target_dir = serde_json::de::from_slice::<CargoMetadata>(&metadata_output)
.context(
"Failed to read the field `target_directory` from the `cargo metadata` output",
)?
.target_directory;
let exercises = exercise_infos
.into_iter()
.map(|mut exercise_info| {
// Leaking to be able to borrow in the watch mode `Table`.
// Leaking is not a problem because the `AppState` instance lives until
// the end of the program.
let path = exercise_info.path().leak();
exercise_info.name.shrink_to_fit();
let name = exercise_info.name.leak();
let dir = exercise_info.dir.map(|mut dir| {
dir.shrink_to_fit();
&*dir.leak()
});
let hint = exercise_info.hint.trim().to_owned();
Exercise {
dir,
name,
path,
test: exercise_info.test,
strict_clippy: exercise_info.strict_clippy,
hint,
done: false,
}
})
.collect::<Vec<_>>();
let mut slf = Self {
current_exercise_ind: 0,
exercises,
n_done: 0,
final_message,
file_buf: Vec::with_capacity(2048),
official_exercises: !Path::new("info.toml").exists(),
target_dir,
};
let state_file_status = slf.update_from_file();
Ok((slf, state_file_status))
}
#[inline]
pub fn current_exercise_ind(&self) -> usize {
self.current_exercise_ind
}
#[inline]
pub fn exercises(&self) -> &[Exercise] {
&self.exercises
}
#[inline]
pub fn n_done(&self) -> u16 {
self.n_done
}
#[inline]
pub fn current_exercise(&self) -> &Exercise {
&self.exercises[self.current_exercise_ind]
}
#[inline]
pub fn target_dir(&self) -> &Path {
&self.target_dir
}
pub fn set_current_exercise_ind(&mut self, ind: usize) -> Result<()> {
if ind >= self.exercises.len() {
bail!(BAD_INDEX_ERR);
}
self.current_exercise_ind = ind;
self.write()
}
pub fn set_current_exercise_by_name(&mut self, name: &str) -> Result<()> {
// O(N) is fine since this method is used only once until the program exits.
// Building a hashmap would have more overhead.
self.current_exercise_ind = self
.exercises
.iter()
.position(|exercise| exercise.name == name)
.with_context(|| format!("No exercise found for '{name}'!"))?;
self.write()
}
pub fn set_pending(&mut self, ind: usize) -> Result<()> {
let exercise = self.exercises.get_mut(ind).context(BAD_INDEX_ERR)?;
if exercise.done {
exercise.done = false;
self.n_done -= 1;
self.write()?;
}
Ok(())
}
fn reset(&self, ind: usize, dir_name: Option<&str>, path: &str) -> Result<()> {
if self.official_exercises {
return EMBEDDED_FILES
.write_exercise_to_disk(
ind,
dir_name.context(
"Official exercises must be nested in the `exercises` directory",
)?,
path,
)
.with_context(|| format!("Failed to reset the exercise {path}"));
}
let output = Command::new("git")
.arg("stash")
.arg("push")
.arg("--")
.arg(path)
.stdin(Stdio::null())
.stdout(Stdio::null())
.output()
.with_context(|| format!("Failed to run `git stash push -- {path}`"))?;
if !output.status.success() {
bail!(
"`git stash push -- {path}` didn't run successfully: {}",
String::from_utf8_lossy(&output.stderr),
);
}
Ok(())
}
pub fn reset_current_exercise(&mut self) -> Result<&'static str> {
self.set_pending(self.current_exercise_ind)?;
let exercise = self.current_exercise();
self.reset(self.current_exercise_ind, exercise.dir, exercise.path)?;
Ok(exercise.path)
}
pub fn reset_exercise_by_ind(&mut self, exercise_ind: usize) -> Result<&'static str> {
if exercise_ind >= self.exercises.len() {
bail!(BAD_INDEX_ERR);
}
self.set_pending(exercise_ind)?;
let exercise = &self.exercises[exercise_ind];
self.reset(exercise_ind, exercise.dir, exercise.path)?;
Ok(exercise.path)
}
fn next_pending_exercise_ind(&self) -> Option<usize> {
if self.current_exercise_ind == self.exercises.len() - 1 {
// The last exercise is done.
// Search for exercises not done from the start.
return self.exercises[..self.current_exercise_ind]
.iter()
.position(|exercise| !exercise.done);
}
// The done exercise isn't the last one.
// Search for a pending exercise after the current one and then from the start.
match self.exercises[self.current_exercise_ind + 1..]
.iter()
.position(|exercise| !exercise.done)
{
Some(ind) => Some(self.current_exercise_ind + 1 + ind),
None => self.exercises[..self.current_exercise_ind]
.iter()
.position(|exercise| !exercise.done),
}
}
pub fn current_solution_path(&self) -> Result<Option<String>> {
if DEBUG_PROFILE {
return Ok(None);
}
let current_exercise = self.current_exercise();
if self.official_exercises {
let dir_name = current_exercise
.dir
.context("Official exercises must be nested in the `exercises` directory")?;
let solution_path = format!("solutions/{dir_name}/{}.rs", current_exercise.name);
EMBEDDED_FILES.write_solution_to_disk(
self.current_exercise_ind,
dir_name,
&solution_path,
)?;
Ok(Some(solution_path))
} else {
let solution_path = if let Some(dir) = current_exercise.dir {
format!("solutions/{dir}/{}.rs", current_exercise.name)
} else {
format!("solutions/{}.rs", current_exercise.name)
};
if Path::new(&solution_path).exists() {
return Ok(Some(solution_path));
}
Ok(None)
}
}
pub fn done_current_exercise(&mut self, writer: &mut StdoutLock) -> Result<ExercisesProgress> {
let exercise = &mut self.exercises[self.current_exercise_ind];
if !exercise.done {
exercise.done = true;
self.n_done += 1;
}
let Some(ind) = self.next_pending_exercise_ind() else {
writer.write_all(RERUNNING_ALL_EXERCISES_MSG)?;
let mut output = Vec::with_capacity(OUTPUT_CAPACITY);
for (exercise_ind, exercise) in self.exercises().iter().enumerate() {
write!(writer, "Running {exercise} ... ")?;
writer.flush()?;
let success = exercise.run(&mut output, &self.target_dir)?;
if !success {
writeln!(writer, "{}\n", "FAILED".red())?;
self.current_exercise_ind = exercise_ind;
// No check if the exercise is done before setting it to pending
// because no pending exercise was found.
self.exercises[exercise_ind].done = false;
self.n_done -= 1;
self.write()?;
return Ok(ExercisesProgress::Pending);
}
writeln!(writer, "{}", "ok".green())?;
}
writer.execute(Clear(ClearType::All))?;
writer.write_all(FENISH_LINE.as_bytes())?;
let final_message = self.final_message.trim();
if !final_message.is_empty() {
writer.write_all(final_message.as_bytes())?;
writer.write_all(b"\n")?;
}
return Ok(ExercisesProgress::AllDone);
};
self.set_current_exercise_ind(ind)?;
Ok(ExercisesProgress::Pending)
}
// Write the state file.
// The file's format is very simple:
// - The first line is a comment.
// - The second line is an empty line.
// - The third line is the name of the current exercise. It must end with `\n` even if there
// are no done exercises.
// - The fourth line is an empty line.
// - All remaining lines are the names of done exercises.
fn write(&mut self) -> Result<()> {
self.file_buf.clear();
self.file_buf
.extend_from_slice(b"DON'T EDIT THIS FILE!\n\n");
self.file_buf
.extend_from_slice(self.current_exercise().name.as_bytes());
self.file_buf.push(b'\n');
for exercise in &self.exercises {
if exercise.done {
self.file_buf.push(b'\n');
self.file_buf.extend_from_slice(exercise.name.as_bytes());
}
}
fs::write(STATE_FILE_NAME, &self.file_buf)
.with_context(|| format!("Failed to write the state file {STATE_FILE_NAME}"))?;
Ok(())
}
}
const CARGO_METADATA_ERR: &str = "Failed to run the command `cargo metadata …`
Did you already install Rust?
Try running `cargo --version` to diagnose the problem.";
const RERUNNING_ALL_EXERCISES_MSG: &[u8] = b"
All exercises seem to be done.
Recompiling and running all exercises to make sure that all of them are actually done.
";
const FENISH_LINE: &str = "+----------------------------------------------------+
| You made it to the Fe-nish line! |
+-------------------------- ------------------------+
\\/\x1b[31m
▒▒ ▒▒▒▒▒▒▒▒ ▒▒▒▒▒▒▒▒ ▒▒
▒▒▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒▒▒
▒▒▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒▒▒
░░▒▒▒▒░░▒▒ ▒▒ ▒▒ ▒▒ ▒▒░░▒▒▒▒
▓▓▓▓▓▓▓▓ ▓▓ ▓▓██ ▓▓ ▓▓██ ▓▓ ▓▓▓▓▓▓▓▓
▒▒▒▒ ▒▒ ████ ▒▒ ████ ▒▒░░ ▒▒▒▒
▒▒ ▒▒▒▒▒▒ ▒▒▒▒▒▒ ▒▒▒▒▒▒ ▒▒
▒▒▒▒▒▒▒▒▒▒▓▓▓▓▓▓▒▒▒▒▒▒▒▒▓▓▓▓▓▓▒▒▒▒▒▒▒▒
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
▒▒▒▒▒▒▒▒▒▒██▒▒▒▒▒▒██▒▒▒▒▒▒▒▒▒▒
▒▒ ▒▒▒▒▒▒▒▒▒▒██████▒▒▒▒▒▒▒▒▒▒ ▒▒
▒▒ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ ▒▒
▒▒ ▒▒ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ ▒▒ ▒▒
▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒
▒▒ ▒▒ ▒▒ ▒▒\x1b[0m
";