step fourty one: reset move HEAD

src/base.rs

@@ -247,6 +247,17 @@ pub fn iter_branch_names() -> Vec<String> {
     branches
 }
 
+pub fn reset(oid: String) {
+    data::update_ref(
+        "HEAD".to_owned(),
+        data::RefValue {
+            symbolic: false,
+            value: oid,
+        },
+        true,
+    )
+}
+
 fn is_ignored(path: &String) -> bool {
     if path.contains(".rgit") {
         true

src/main.rs

@@ -65,6 +65,11 @@ fn main() {
                 .arg(Arg::with_name("start_point").index(2).default_value("@")),
         )
         .subcommand(SubCommand::with_name("status").about("check current branch"))
+        .subcommand(
+            SubCommand::with_name("reset")
+                .about("Move the current content and HEAD to given commit with dereferencing")
+                .arg(Arg::with_name("commit").index(1).required(true)),
+        )
         .get_matches();
 
     match matches.subcommand_name() {
@@ -80,6 +85,7 @@ fn main() {
         Some("k") => k(),
         Some("branch") => branch(matches),
         Some("status") => status(),
+        Some("reset") => reset(matches),
         _ => println!("unknown sub command"),
     }
 }
@@ -247,3 +253,10 @@ fn status() {
         println!("HEAD detached at {}", &base::get_oid("@".to_owned())[1..10])
     }
 }
+
+fn reset(matches: ArgMatches) {
+    if let Some(cmd_matches) = matches.subcommand_matches("reset") {
+        let oid = base::get_oid(cmd_matches.value_of("commit").unwrap().to_owned());
+        base::reset(oid);
+    }
+}