Extract exercise struct to encapsulate path logic

src/exercise.rs

@@ -0,0 +1,72 @@
+use std::fmt::{self, Display, Formatter};
+use std::fs::{remove_file};
+use std::path::{PathBuf};
+use std::process::{self, Command, Output};
+use serde::Deserialize;
+
+const RUSTC_COLOR_ARGS: &[&str] = &["--color", "always"];
+
+fn temp_file() -> String {
+    format!("./temp_{}", process::id())
+}
+
+#[derive(Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum Mode {
+    Compile,
+    Test,
+}
+
+#[derive(Deserialize)]
+pub struct ExerciseList {
+    pub exercises: Vec<Exercise>,
+}
+
+#[derive(Deserialize)]
+pub struct Exercise {
+    pub path: PathBuf,
+    pub mode: Mode,
+}
+
+impl Exercise {
+    pub fn compile(&self) -> Output {
+        match self.mode {
+            Mode::Compile => Command::new("rustc")
+                .args(&[self.path.to_str().unwrap(), "-o", &temp_file()])
+                .args(RUSTC_COLOR_ARGS)
+                .output(),
+            Mode::Test => Command::new("rustc")
+                .args(&["--test", self.path.to_str().unwrap(), "-o", &temp_file()])
+                .args(RUSTC_COLOR_ARGS)
+                .output(),
+        }
+        .expect("Failed to run 'compile' command.")
+    }
+
+    pub fn run(&self) -> Output {
+        Command::new(&temp_file())
+            .output()
+            .expect("Failed to run 'run' command")
+    }
+
+    pub fn clean(&self) {
+        let _ignored = remove_file(&temp_file());
+    }
+}
+
+impl Display for Exercise {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{}", self.path.to_str().unwrap())
+    }
+}
+
+#[test]
+fn test_clean() {
+    std::fs::File::create(&temp_file()).unwrap();
+    let exercise = Exercise {
+        path: PathBuf::from("example.rs"),
+        mode: Mode::Test,
+    };
+    exercise.clean();
+    assert!(!std::path::Path::new(&temp_file()).exists());
+}