Add rust file/dir usertest (#65)

usertest/src/main.rs

@@ -111,6 +111,40 @@ fn test_write() {
     println!(" OK");
 }
 
+fn test_rust_file() {
+    print!("Testing rust file operations ...");
+    use std::fs::{self, File};
+    use std::io::{Read, Write};
+
+    let path = "/tmp/rust_fs_test.txt";
+    {
+        let mut file = File::create(path).expect("Failed to create file");
+        file.write_all(b"Hello, Rust!")
+            .expect("Failed to write to file");
+    }
+    {
+        let mut file = File::open(path).expect("Failed to open file");
+        let mut contents = String::new();
+        file.read_to_string(&mut contents)
+            .expect("Failed to read from file");
+        assert_eq!(contents, "Hello, Rust!");
+    }
+    fs::remove_file(path).expect("Failed to delete file");
+    println!(" OK");
+}
+
+fn test_rust_dir() {
+    print!("Testing rust directory operations ...");
+    use std::fs;
+    use std::path::Path;
+
+    let dir_path = "/tmp/rust_dir_test";
+    fs::create_dir(dir_path).expect("Failed to create directory");
+    assert!(Path::new(dir_path).exists());
+    fs::remove_dir(dir_path).expect("Failed to delete directory");
+    println!(" OK");
+}
+
 fn run_test(test_fn: fn()) {
     // Fork a new process to run the test
     unsafe {
@@ -142,6 +176,8 @@ fn main() {
     run_test(test_fork);
     run_test(test_read);
     run_test(test_write);
+    run_test(test_rust_file);
+    run_test(test_rust_dir);
     let end = std::time::Instant::now();
     println!("All tests passed in {} ms", (end - start).as_millis());
 }