step fourty five: compare working tree to a commit

src/base.rs

@@ -2,6 +2,7 @@ use std::collections::{HashMap, HashSet, VecDeque};
 use std::fs;
 use std::io;
 use std::path::Path;
+use walkdir::WalkDir;
 #[path = "data.rs"]
 mod data;
 
@@ -304,6 +305,25 @@ pub fn get_tree(oid: String, base_path: String) -> HashMap<String, String> {
     result
 }
 
+pub fn get_working_tree() -> HashMap<String, String> {
+    let mut result = HashMap::new();
+
+    for entry in WalkDir::new(".") {
+        let item = entry.unwrap();
+        let relative_path = item.path().strip_prefix("./").unwrap();
+        let metadata = item.metadata().unwrap();
+        let path = item.path().to_str().unwrap().to_owned();
+        if metadata.is_file() && !is_ignored(&path.clone()) {
+            let content = fs::read(path.clone()).unwrap();
+            result.insert(
+                relative_path.to_str().unwrap().to_owned(),
+                data::hash_object(&content, "blob".to_owned()),
+            );
+        }
+    }
+    return result;
+}
+
 fn empty_current_directory(dir: &str) -> io::Result<()> {
     // Delete current directory, except the ignored directories and files
     for entry in fs::read_dir(dir)? {

src/main.rs

@@ -76,6 +76,11 @@ fn main() {
                 .about("Show diff from a commit")
                 .arg(Arg::with_name("oid").index(1).default_value("@")),
         )
+        .subcommand(
+            SubCommand::with_name("diff")
+                .about("Compare the working tree with the given commit")
+                .arg(Arg::with_name("commit").index(1).default_value("@")),
+        )
         .get_matches();
 
     match matches.subcommand_name() {
@@ -93,6 +98,7 @@ fn main() {
         Some("status") => status(),
         Some("reset") => reset(matches),
         Some("show") => show(matches),
+        Some("diff") => difference(matches),
         _ => println!("unknown sub command"),
     }
 }
@@ -280,6 +286,18 @@ fn show(matches: ArgMatches) {
     }
 }
 
+fn difference(matches: ArgMatches) {
+    if let Some(cmd_matches) = matches.subcommand_matches("diff") {
+        let oid = base::get_oid(cmd_matches.value_of("commit").unwrap().to_owned());
+        let commit = base::get_commit(oid);
+        let result = diff::diff_trees(
+            base::get_tree(commit.tree, "".to_owned()),
+            base::get_working_tree(),
+        );
+        println!("{}", result);
+    }
+}
+
 fn print_commit(oid: String, commit: &base::Commit, mut refs: HashMap<String, Vec<String>>) {
     let ref_str = if refs.contains_key(&oid) {
         refs.get_mut(&oid).unwrap().join(", ")