Add more tests

src/main.rs

@@ -154,7 +154,7 @@ impl Program {
             'l' => self.add_var(arguments),
             'f' => self.add_func(arguments),
             '#' => {} // Do nothing for comments
-            _ => panic!("SyntaxError: No such opcode: {}", self.pc),
+            _ => panic!("SyntaxError at opcode {}: Unknown opcode {}", self.pc, opcode),
         }
     }
 
@@ -218,4 +218,38 @@ mod tests {
     fn test_undefined_variable() {
         make_program("p$v").run();
     }
+
+    #[test]
+    #[should_panic]
+    fn test_undefined_function() {
+        make_program("p*x").run();
+    }
+
+    #[test]
+    fn test_factory() {
+        let prog = make_program("lhHello\nlwWorld\np$h $w");
+        let vec_to_check: Vec<String> = vec!["lhHello", "lwWorld", "p$h $w"].into_iter().map(|s| s.to_string()).collect();
+
+        assert_eq!(prog.data, vec_to_check);
+    }
+
+    #[test]
+    fn test_args() {
+        let mut prog = make_program("lhHello\nlwWorld\np$h $w");
+        prog.run();
+
+        let args_to_check: HashMap<char, String> = [('h', String::from("Hello")), ('w', String::from("World"))].iter().cloned().collect();
+
+        assert_eq!(prog.vars, args_to_check);
+    }
+    
+    #[test]
+    fn test_funcs() {
+        let mut prog = make_program("fxa10-10\nfys10-5\np*x *y");
+        prog.run();
+
+        let funcs_to_check: HashMap<char, String> = [('x', String::from("a10-10")), ('y', String::from("s10-5"))].iter().cloned().collect();
+
+        assert_eq!(prog.funcs, funcs_to_check);
+    }
 }