Work-around for fatal error when using overloaded functions with vari…

…able parameters. #48

sass/chroma/_internals.scss

@@ -132,16 +132,16 @@
 
 // _safe-call()
 //
-// LibSass incorrectly throws an error when using call() with an overloaded
-// function; e.g. rgba(). To work-around this bug, we call rgba() directly
-// instead of with call().
+// LibSass incorrectly throws an error when using the variable argument
+// indicator, ..., with an overloaded function; e.g. rgba(). To work-around this
+// bug, we call rgba() with direct parameters.
 //
 // @TODO: Remove when the fix for https://github.com/sass/libsass/issues/2205 is released.
 //
 // Style guide: internals._safe-call
 @function _safe-call($function, $parameters...) {
   @if $function == rgba {
-    @return rgba($parameters...);
+    @return rgba(nth($parameters, 1), nth($parameters, 2));
   }
   @return call($function, $parameters...);
 }

test/fixtures/internals/_safe-call/input.scss

@@ -0,0 +1,8 @@
+@import 'chroma';
+
+$function: rgba;
+$parameters: #fff, .5;
+
+.test {
+  color: _safe-call($function, $parameters...);
+}

test/fixtures/internals/_safe-call/output.css

@@ -0,0 +1,2 @@
+.test {
+  color: rgba(255, 255, 255, 0.5); }

test/test_internals.js

@@ -68,4 +68,10 @@ describe('@import "chroma/internals";', function() {
       return sassyTest.renderFixture('_is-keyword-string');
     });
   });
+
+  describe('@function _safe-call()', function() {
+    it('should call an overloaded function without error with LibSass before libsass#2205', function() {
+      return sassyTest.renderFixture('_safe-call');
+    });
+  });
 });