diff --git a/src/main.rs b/src/main.rs
index ef83311..09ee348 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -100,7 +100,7 @@ fn main() {
     if !args.is_present("no-vcs-ignore") {
         let gitignore_path = cwd.join(".gitignore");
         if gitignore_path.exists() {
-            debug!("Found .gitignore file: {}", gitignore_path.to_str().unwrap());
+            debug!("Found .gitignore file: {:?}", gitignore_path);
 
             gitignore_file = gitignore::parse(&gitignore_path).ok();
         }
diff --git a/src/notification_filter.rs b/src/notification_filter.rs
index a09b910..15eef73 100644
--- a/src/notification_filter.rs
+++ b/src/notification_filter.rs
@@ -19,18 +19,6 @@ pub enum NotificationError {
     Io(io::Error)
 }
 
-impl From<io::Error> for NotificationError {
-    fn from(err: io::Error) -> NotificationError {
-        NotificationError::Io(err)
-    }
-}
-
-impl From<PatternError> for NotificationError {
-    fn from(err: PatternError) -> NotificationError {
-        NotificationError::BadPattern(err)
-    }
-}
-
 impl NotificationFilter {
     pub fn new(current_dir: &Path, ignore_file: Option<gitignore::PatternSet>) -> Result<NotificationFilter, io::Error> {
         let canonicalized = try!(current_dir.canonicalize());
@@ -43,18 +31,14 @@ impl NotificationFilter {
         })
     }
 
-    pub fn add_extension(&mut self, extension: &str) -> Result<(), NotificationError> {
-        let mut pattern = String::new();
-
-        for ext in extension.split(",") {
-            pattern.clear();
-            pattern.push_str("*");
-
-            if !ext.starts_with(".") {
-                pattern.push_str(".");
-            }
-            pattern.push_str(ext);
+    pub fn add_extension(&mut self, extensions: &str) -> Result<(), NotificationError> {
+        let patterns: Vec<String> = extensions
+            .split(",")
+            .filter(|ext| !ext.is_empty())
+            .map(|ext| format!("*.{}", ext.replace(".", "")))
+            .collect();
 
+        for pattern in patterns {
             try!(self.add_filter(&pattern));
         }
 
@@ -65,6 +49,8 @@ impl NotificationFilter {
         let compiled = try!(self.pattern_for(pattern));
         self.filters.push(compiled);
 
+        debug!("Adding filter: {}", pattern);
+
         Ok(())
     }
 
@@ -72,6 +58,8 @@ impl NotificationFilter {
         let compiled = try!(self.pattern_for(pattern));
         self.ignores.push(compiled);
 
+        debug!("Adding ignore: {}", pattern);
+
         Ok(())
     }
 
@@ -114,3 +102,15 @@ impl NotificationFilter {
         self.filters.len() > 0
     }
 }
+
+impl From<io::Error> for NotificationError {
+    fn from(err: io::Error) -> NotificationError {
+        NotificationError::Io(err)
+    }
+}
+
+impl From<PatternError> for NotificationError {
+    fn from(err: PatternError) -> NotificationError {
+        NotificationError::BadPattern(err)
+    }
+}