Add support for requiring a platform-specific stylesheet

Add a getPlatform method to the native object that
is used for requiring the platform stylesheet from
within window.coffee after the atom.css is required.

This is used to provide non-native scrollbars on Linux
for an improved look and feel.

Atom-Linux/native_handler.cpp

@@ -57,7 +57,8 @@ NativeHandler::NativeHandler() :
       "absolute", "list", "isFile", "isDirectory", "remove", "asyncList",
       "open", "openDialog", "quit", "writeToPasteboard", "readFromPasteboard",
       "showDevTools", "newWindow", "saveDialog", "exit", "watchPath",
-      "unwatchPath", "makeDirectory", "move", "moveToTrash", "md5ForPath" };
+      "unwatchPath", "makeDirectory", "move", "moveToTrash", "md5ForPath",
+      "getPlatform" };
   int arrayLength = sizeof(functionNames) / sizeof(const char *);
   for (int i = 0; i < arrayLength; i++) {
     const char *functionName = functionNames[i];
@@ -513,6 +514,8 @@ bool NativeHandler::Execute(const CefString& name, CefRefPtr<CefV8Value> object,
     UnwatchPath(name, object, arguments, retval, exception);
   else if (name == "md5ForPath")
     Digest(name, object, arguments, retval, exception);
+  else if (name == "getPlatform")
+    retval = CefV8Value::CreateString("linux");
   else
     cout << "Unhandled -> " + name.ToString() << " : "
         << arguments[0]->GetStringValue().ToString() << endl;

Atom/src/native_handler.mm

@@ -33,7 +33,7 @@ void throwException(const CefRefPtr<CefV8Value>& global, CefRefPtr<CefV8Exceptio
 NativeHandler::NativeHandler() : CefV8Handler() {  
   std::string extensionCode =  "var $native = {}; (function() {";
   
-  const char *functionNames[] = {"exists", "alert", "read", "write", "absolute", "list", "isFile", "isDirectory", "remove", "asyncList", "open", "openDialog", "quit", "writeToPasteboard", "readFromPasteboard", "showDevTools", "toggleDevTools", "newWindow", "saveDialog", "exit", "watchPath", "unwatchPath", "makeDirectory", "move", "moveToTrash", "reload", "lastModified", "md5ForPath", "exec"};
+  const char *functionNames[] = {"exists", "alert", "read", "write", "absolute", "list", "isFile", "isDirectory", "remove", "asyncList", "open", "openDialog", "quit", "writeToPasteboard", "readFromPasteboard", "showDevTools", "toggleDevTools", "newWindow", "saveDialog", "exit", "watchPath", "unwatchPath", "makeDirectory", "move", "moveToTrash", "reload", "lastModified", "md5ForPath", "exec", "getPlatform"};
   NSUInteger arrayLength = sizeof(functionNames) / sizeof(const char *);
   for (NSUInteger i = 0; i < arrayLength; i++) {
     std::string functionName = std::string(functionNames[i]);
@@ -525,5 +525,11 @@ bool NativeHandler::Execute(const CefString& name,
     
     return true;
   }
+  else if (name == "getPlatform") {
+    NSString *platform = @"mac";
+    retval = CefV8Value::CreateString([platform UTF8String]);
+
+    return true;
+  }
   return false;
 };

spec/app/native-spec.coffee

@@ -0,0 +1,7 @@
+describe 'Native', ->
+
+  describe '$native.getPlatform()', ->
+    it 'returns a non-empty value', ->
+      platform = $native.getPlatform()
+      expect(platform).not.toBe ''
+      expect(platform.length).toBeGreaterThan(0)

src/app/window.coffee

@@ -56,6 +56,7 @@ windowAdditions =
 
   requireStylesheet: (path) ->
     fullPath = require.resolve(path)
+    return unless fs.isFile(fullPath)
     window.applyStylesheet(fullPath, fs.read(fullPath))
 
   applyStylesheet: (id, text) ->
@@ -106,3 +107,4 @@ require 'underscore-extensions'
 
 requireStylesheet 'reset.css'
 requireStylesheet 'atom.css'
+requireStylesheet "#{$native.getPlatform()}.css"

static/linux.css

@@ -0,0 +1,13 @@
+::-webkit-scrollbar-corner {
+  background-color: transparent;
+}
+
+::-webkit-scrollbar {
+  width: 10px;
+  height: 10px;
+}
+
+::-webkit-scrollbar-thumb {
+  -webkit-border-radius: 2px;
+  background: rgba(150, 150, 150, .33);
+}