Raise if Class#native_alias is used on undef meth

elia · elia · commit 3538cf4eb1f1 · 2015-01-26T22:32:47.000+01:00
fixes #692
diff --git a/spec/opal/stdlib/native/native_alias_spec.rb b/spec/opal/stdlib/native/native_alias_spec.rb
@@ -0,0 +1,19 @@
+require 'native'
+
+describe "Class#native_alias" do
+  it "exposes a method to javascript without the '$' prefix" do
+    klass = Class.new {
+      def a
+        2
+      end
+
+      native_alias :a, :a
+    }
+    instance = klass.new
+    `instance.a()`.should == 2
+  end
+
+  it "raises if the aliased method isn't defined" do
+    lambda { Class.new { native_alias :a, :not_a_method } }.should raise_error(NameError)
+  end
+end
diff --git a/spec/opal/stdlib/native/native_module_spec.rb b/spec/opal/stdlib/native/native_module_spec.rb
diff --git a/stdlib/native.rb b/stdlib/native.rb
@@ -538,8 +538,14 @@ def native_module
 end
 
 class Class
-  def native_alias(jsid, mid)
-    `#{self}.$$proto[#{jsid}] = #{self}.$$proto['$' + #{mid}]`
+  def native_alias(new_jsid, existing_mid)
+    %x{
+      var aliased = #{self}.$$proto['$' + #{existing_mid}];
+      if (!aliased) {
+        #{raise NameError, "undefined method `#{existing_mid}' for class `#{inspect}'"};
+      }
+      #{self}.$$proto[#{new_jsid}] = aliased;
+    }
   end
 
   alias native_class native_module
