Show file colours for symlink targets

This requires the dir field to store a reference to the path that
created it, so that path can be used to join onto the filename so it can
be properly statted.

dir.rs

@@ -8,13 +8,15 @@ use file::File;
 // differently if a certain other file exists.
 
 pub struct Dir<'a> {
-    contents: Vec<Path>,
+    pub contents: Vec<Path>,
+    pub path: Path,
 }
 
 impl<'a> Dir<'a> {
     pub fn readdir(path: Path) -> IoResult<Dir<'a>> {
         fs::readdir(&path).map(|paths| Dir {
             contents: paths,
+            path: path.clone(),
         })
     }
 

file.rs

@@ -110,11 +110,11 @@ impl<'a> File<'a> {
         let displayed_name = self.file_colour().paint(self.name);
         if self.stat.kind == io::TypeSymlink {
             match fs::readlink(self.path) {
-                Ok(path) => format!("{} {} {}", displayed_name, Fixed(244).paint("=>"), path.display()),
-                Err(e) => {
-                    println!("{}", e);
-                    displayed_name
-                },
+                Ok(path) => {
+                    let target_path = if path.is_absolute() { path } else { self.dir.path.join(path) };
+                    format!("{} {}", displayed_name, self.target_file_name_and_arrow(target_path))
+                }
+                Err(_) => displayed_name,
             }
         }
         else {
@@ -122,6 +122,29 @@ impl<'a> File<'a> {
         }
     }
 
+    fn target_file_name_and_arrow(&self, target_path: Path) -> String {
+        let filename = target_path.as_str().unwrap();
+        let link_target = fs::stat(&target_path).map(|stat| File {
+            path:  &target_path,
+            dir:   self.dir,
+            stat:  stat,
+            name:  filename,
+            ext:   File::ext(filename),
+            parts: vec![],  // not needed
+        });
+
+        // Statting a path usually fails because the file at the other
+        // end doesn't exist. Show this by highlighting the target
+        // file in red instead of displaying an error, because the
+        // error would be shown out of context and it's almost always
+        // that reason anyway.
+
+        match link_target {
+            Ok(file) => format!("{} {}", Fixed(244).paint("=>"), file.file_colour().paint(filename)),
+            Err(_)   => format!("{} {}", Red.paint("=>"), Red.underline().paint(filename)),
+        }
+    }
+
     fn file_size(&self, use_iec_prefixes: bool) -> String {
         // Don't report file sizes for directories. I've never looked
         // at one of those numbers and gained any information from it.