Update tests

tests/advanced6.rs

@@ -0,0 +1,35 @@
+extern crate rustijvm;
+
+use std::sync::{Arc, Mutex};
+use std::io::{Cursor, Seek, SeekFrom, Read};
+
+fn run_calc(input: &'static str, expected: &str) {
+    let rc = Arc::new(Mutex::new(Cursor::new(Vec::new())));
+    let mut machine = rustijvm::Machine::new_from_file("files/advanced/SimpleCalc.ijvm").unwrap();
+    machine.set_input(Box::new(input.as_bytes()));
+    machine.set_output(rc.clone());
+    machine.run().unwrap();
+
+    let mut out = rc.lock().unwrap();
+    let mut output = String::new();
+
+    out.seek(SeekFrom::Start(0)).unwrap();
+    out.read_to_string(&mut output).unwrap();
+
+    assert_eq!(output, expected);
+}
+
+#[test]
+fn advanced6_recurse1() {
+    run_calc("2!?.", "2\n");
+}
+
+#[test]
+fn advanced6_recurse2() {
+    run_calc("7!?.", "5040\n");
+}
+
+#[test]
+fn advanced6_recurse3() {
+    run_calc("8!?.", "40320\n");
+}