let version fail gracefully

src/game.rs

@@ -55,13 +55,19 @@ pub struct Version {
     pub minor: u8,
 }
 
+#[derive(Debug)]
+pub struct InvalidVersion;
+
 impl Version {
-    fn from(str: &str) -> Version {
+    fn from(str: &str) -> Result<Version, InvalidVersion> {
         let parts: Vec<&str> = str.split(".").collect();
-        assert_eq!(parts.len(), 2);
-        Version {
-            major: parts[0].parse().unwrap(),
-            minor: parts[1].parse().unwrap(),
+        if parts.len() == 2 {
+            Ok(Version {
+                major: parts[0].parse().unwrap(),
+                minor: parts[1].parse().unwrap(),
+            })
+        } else {
+            Err (InvalidVersion)
         }
     }
 }
@@ -142,7 +148,10 @@ impl Game {
         for segment in segments {
             if segment.starts_with("# BITSY VERSION") {
                 let segment = segment.replace("# BITSY VERSION ", "");
-                version = Some(Version::from(&segment));
+                let segment = Version::from(&segment);
+                if segment.is_ok() {
+                    version = Some(segment.unwrap());
+                }
             } else if segment.starts_with("! ROOM_FORMAT") {
                 let segment = segment.replace("! ROOM_FORMAT ", "");
                 room_format = Some(RoomFormat::from(&segment).unwrap());