Added writing capabilities

src/command/dedupe.rs

@@ -21,6 +21,7 @@ pub fn get_command<'a>() -> Command<'a, str>{
                     for path in playlists {
                         let playlist = Playlist::read(path)?;
                         println!("{:?}", playlist);
+                        playlist.write(path)?
                     }
                     Ok(())
                 },

src/lib/m3u.rs

@@ -1,11 +1,11 @@
 use std::fs::File;
-use std::io::{self, BufRead};
+use std::io::{self, BufRead, Write};
 use std::path::Path;
 use std::string::String;
 
-fn read_lines<P>(filename: P) -> io::Result<io::Lines<io::BufReader<File>>>
+fn read_lines<P>(path: P) -> io::Result<io::Lines<io::BufReader<File>>>
     where P: AsRef<Path>, {
-    let file = File::open(filename)?;
+    let file = File::open(path)?;
     Ok(io::BufReader::new(file).lines())
 }
 
@@ -16,8 +16,14 @@ pub struct Playlist {
 }
 
 impl Playlist {
+    pub fn new(path: &str, tracks: Vec<String>) -> Playlist {
+        Playlist {
+            path: String::from(path),
+            tracks: Box::new(tracks)
+        }
+    }
+
     pub fn read(path: &str) -> Result<Playlist, io::Error> {
-        let playlist_path: String = String::from(path);
         let mut playlist_tracks: Vec<String> = Vec::new();
         let lines = read_lines(path)?;
         lines.for_each(|read_line| {
@@ -28,6 +34,16 @@ impl Playlist {
                 }
             }
         });
-        Ok(Playlist { path: playlist_path, tracks: Box::new(playlist_tracks) })
+        Ok(Playlist::new(path, playlist_tracks))
+    }
+
+    pub fn write(&self, path: &str) -> Result<(), io::Error> {
+        let mut file = File::create(path)?;
+        file.write("#EXTM3U\n".as_bytes())?;
+        for track in &*self.tracks {
+            file.write(track.as_bytes())?;
+            file.write("\n".as_bytes())?;
+        }
+        Ok(())
     }
 }