step six: add types to objects

src/data.rs

@@ -10,22 +10,33 @@ pub fn init() -> std::io::Result<()> {
     Ok(())
 }
 
-pub fn hash_object(content: &Vec<u8>) -> String {
+pub fn hash_object(content: &Vec<u8>, _type: String) -> String {
+    let mut raw = format!("{}\u{0}", _type).into_bytes();
+    let mut data = content.clone();
+    raw.append(&mut data);
+
     let mut hasher = Sha1::new();
-    hasher.update(content);
+    hasher.update(&raw);
     let digest = &hasher.finalize();
     let s = format!("{:x}", digest);
 
-    fs::write(
-        format!("{}/{}/{}", RGIT_DIR, "objects", s),
-        content.as_slice(),
-    )
-    .expect("Failed to write object");
+    fs::write(format!("{}/{}/{}", RGIT_DIR, "objects", s), raw.as_slice())
+        .expect("Failed to write object");
 
     return s;
 }
 
-pub fn get_object(hash: String) -> String {
-    return fs::read_to_string(format!("{}/{}/{}", RGIT_DIR, "objects", hash))
+pub fn get_object(hash: String, expected: String) -> String {
+    let mut content = fs::read_to_string(format!("{}/{}/{}", RGIT_DIR, "objects", hash))
         .expect("Could not find a matching object");
+
+    let index = content.find(char::from(0)).expect("object type missing");
+    let data = content.split_off(index + 1);
+
+    if expected != "".to_owned() {
+        // Compare the type
+        assert_eq!(expected, content);
+    }
+
+    return data;
 }

src/main.rs

@@ -39,14 +39,17 @@ fn hash_object(matches: ArgMatches) {
     if let Some(cmd_matches) = matches.subcommand_matches("hash-object") {
         let content = fs::read(cmd_matches.value_of("file").unwrap())
             .expect("Something went wrong reading the provided file");
-        let hash = data::hash_object(&content);
+        let hash = data::hash_object(&content, "blob".to_owned());
         println!("{}", hash);
     }
 }
 
 fn cat_file(matches: ArgMatches) {
     if let Some(cmd_matches) = matches.subcommand_matches("cat-file") {
-        let file_contents = data::get_object(cmd_matches.value_of("hash").unwrap().to_owned());
+        let file_contents = data::get_object(
+            cmd_matches.value_of("hash").unwrap().to_owned(),
+            "".to_owned(),
+        );
         println!("{}", file_contents)
     }
 }