1 files changed, 138 insertions, 0 deletions
diff --git a/src/info_file.rs b/src/info_file.rs
new file mode 100644
index 0000000..f27d018
--- /dev/null
+++ b/src/info_file.rs
@@ -0,0 +1,138 @@
+use anyhow::{bail, Context, Error, Result};
+use serde::Deserialize;
+use std::{fs, io::ErrorKind};
+
+use crate::{embedded::EMBEDDED_FILES, exercise::RunnableExercise};
+
+/// Deserialized from the `info.toml` file.
+#[derive(Deserialize)]
+pub struct ExerciseInfo {
+    /// Exercise's unique name.
+    pub name: String,
+    /// Exercise's directory name inside the `exercises/` directory.
+    pub dir: Option<String>,
+    /// Run `cargo test` on the exercise.
+    #[serde(default = "default_true")]
+    pub test: bool,
+    /// Deny all Clippy warnings.
+    #[serde(default)]
+    pub strict_clippy: bool,
+    /// The exercise's hint to be shown to the user on request.
+    pub hint: String,
+    /// The exercise is already solved. Ignore it when checking that all exercises are unsolved.
+    #[serde(default)]
+    pub skip_check_unsolved: bool,
+}
+#[inline(always)]
+const fn default_true() -> bool {
+    true
+}
+
+impl ExerciseInfo {
+    /// Path to the exercise file starting with the `exercises/` directory.
+    pub fn path(&self) -> String {
+        let mut path = if let Some(dir) = &self.dir {
+            // 14 = 10 + 1 + 3
+            // exercises/ + / + .rs
+            let mut path = String::with_capacity(14 + dir.len() + self.name.len());
+            path.push_str("exercises/");
+            path.push_str(dir);
+            path.push('/');
+            path
+        } else {
+            // 13 = 10 + 3
+            // exercises/ + .rs
+            let mut path = String::with_capacity(13 + self.name.len());
+            path.push_str("exercises/");
+            path
+        };
+
+        path.push_str(&self.name);
+        path.push_str(".rs");
+
+        path
+    }
+
+    /// Path to the solution file starting with the `solutions/` directory.
+    pub fn sol_path(&self) -> String {
+        let mut path = if let Some(dir) = &self.dir {
+            // 14 = 10 + 1 + 3
+            // solutions/ + / + .rs
+            let mut path = String::with_capacity(14 + dir.len() + self.name.len());
+            path.push_str("solutions/");
+            path.push_str(dir);
+            path.push('/');
+            path
+        } else {
+            // 13 = 10 + 3
+            // solutions/ + .rs
+            let mut path = String::with_capacity(13 + self.name.len());
+            path.push_str("solutions/");
+            path
+        };
+
+        path.push_str(&self.name);
+        path.push_str(".rs");
+
+        path
+    }
+}
+
+impl RunnableExercise for ExerciseInfo {
+    #[inline]
+    fn name(&self) -> &str {
+        &self.name
+    }
+
+    #[inline]
+    fn strict_clippy(&self) -> bool {
+        self.strict_clippy
+    }
+
+    #[inline]
+    fn test(&self) -> bool {
+        self.test
+    }
+}
+
+/// The deserialized `info.toml` file.
+#[derive(Deserialize)]
+pub struct InfoFile {
+    /// For possible breaking changes in the future for third-party exercises.
+    pub format_version: u8,
+    /// Shown to users when starting with the exercises.
+    pub welcome_message: Option<String>,
+    /// Shown to users after finishing all exercises.
+    pub final_message: Option<String>,
+    /// List of all exercises.
+    pub exercises: Vec<ExerciseInfo>,
+}
+
+impl InfoFile {
+    /// Official exercises: Parse the embedded `info.toml` file.
+    /// Third-party exercises: Parse the `info.toml` file in the current directory.
+    pub fn parse() -> Result<Self> {
+        // Read a local `info.toml` if it exists.
+        let slf = match fs::read_to_string("info.toml") {
+            Ok(file_content) => toml_edit::de::from_str::<Self>(&file_content)
+                .context("Failed to parse the `info.toml` file")?,
+            Err(e) => {
+                if e.kind() == ErrorKind::NotFound {
+                    return toml_edit::de::from_str(EMBEDDED_FILES.info_file)
+                        .context("Failed to parse the embedded `info.toml` file");
+                }
+
+                return Err(Error::from(e).context("Failed to read the `info.toml` file"));
+            }
+        };
+
+        if slf.exercises.is_empty() {
+            bail!("{NO_EXERCISES_ERR}");
+        }
+
+        Ok(slf)
+    }
+}
+
+const NO_EXERCISES_ERR: &str = "There are no exercises yet!
+If you are developing third-party exercises, add at least one exercise before testing.";