Open folders and plain text files dropped dock icon

Closes #103

native/atom_application.mm

@@ -81,6 +81,7 @@
 
   if (cleanArgc > 0) {
     NSString *path = [NSString stringWithUTF8String:cleanArgv[0]];
+    path = [self standardizePathToOpen:path withArguments:arguments];
     NSString *executedFromPath =[arguments objectForKey:@"executed-from"];
     if (![path isAbsolutePath] && executedFromPath) {
       path = [executedFromPath stringByAppendingPathComponent:path];
@@ -93,6 +94,16 @@
   return arguments;
 }
 
++ (NSString *)standardizePathToOpen:(NSString *)path withArguments:(NSDictionary *)arguments {
+  NSString *standardizedPath = path;
+  NSString *executedFromPath = [arguments objectForKey:@"executed-from"];
+  if (![standardizedPath isAbsolutePath] && executedFromPath) {
+    standardizedPath = [executedFromPath stringByAppendingPathComponent:standardizedPath];
+  }
+  standardizedPath = [standardizedPath stringByStandardizingPath];
+  return standardizedPath;
+}
+
 + (NSString *)supportDirectory {
   NSString *cachePath = [NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES) objectAtIndex:0];
   NSString *executableName = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleExecutable"];
@@ -166,6 +177,14 @@
 
 # pragma mark NSApplicationDelegate
 
+- (void)application:(NSApplication *)sender openFiles:(NSArray *)filenames {
+  for (int i = 0; i < [filenames count]; i++) {
+    NSString *path = [filenames objectAtIndex:i];
+    path = [[self class] standardizePathToOpen:path withArguments:self.arguments];
+    [self open:path];
+  }
+}
+
 - (void)applicationWillFinishLaunching:(NSNotification *)notification {
   _backgroundWindowController = [[AtomWindowController alloc] initInBackground];
 

native/mac/info.plist

@@ -20,6 +20,16 @@
 	<string>????</string>
 	<key>CFBundleVersion</key>
 	<string>1.0</string>
+	<key>CFBundleDocumentTypes</key>
+	<array>
+		<dict>
+			<key>LSItemContentTypes</key>
+			<array>
+				<string>public.folder</string>
+				<string>public.plain-text</string>
+			</array>
+		</dict>
+	</array>
 	<key>NSMainNibFile</key>
 	<string>MainMenu</string>
 	<key>NSPrincipalClass</key>