Add `File.exists?` to MRuby

This also enables file checking to the `Image` class for MRI and MRuby
(on the web, a “failed to load resource” already appears). Also, all
exceptions will now be printed in MRuby, yay!

2 files changed, 5 insertions, 15 deletions

diff --git a/lib/ruby2d/exceptions.rb b/lib/ruby2d/exceptions.rb
index 84880e1..687ab11 100644
--- a/lib/ruby2d/exceptions.rb
+++ b/lib/ruby2d/exceptions.rb
@@ -2,14 +2,5 @@
 
 module Ruby2D
   class Error < StandardError
-    def colorize(msg, c); "\e[#{c}m#{msg}\e[0m" end
-    def error(msg); colorize(msg, '4;31') end
-    def bold(msg); colorize(msg, '1') end
-    
-    def initialize(msg)
-      super(msg)
-      puts error("\nRuby 2D Error:") << " #{msg}" <<
-      bold("\nOccurred in:\n  #{caller.last}\n")
-    end
   end
 end
diff --git a/lib/ruby2d/image.rb b/lib/ruby2d/image.rb
index 7938bea..587a3c0 100644
--- a/lib/ruby2d/image.rb
+++ b/lib/ruby2d/image.rb
@@ -9,12 +9,11 @@ module Ruby2D
     
     def initialize(x, y, path)
       
-      # TODO: Check if file exists
-      #   `File.exists?` is not available in MRuby
-      #   Ideally would do:
-      #     unless File.exists? path
-      #       raise Error, "Cannot find image file `#{path}`"
-      #     end
+      unless RUBY_ENGINE == 'opal'
+        unless File.exists? path
+          raise Error, "Cannot find image file `#{path}`"
+        end
+      end
       
       @type_id = 3
       @x, @y, @path = x, y, path