[Sass] [SCSS] Support expression() and calc().

lib/sass/scss/parser.rb

@@ -520,7 +520,12 @@ MESSAGE
 
       def function
         return unless name = tok(FUNCTION)
-        [name, str{ss}, expr, tok!(/\)/)]
+        if name == "expression(" || name == "calc("
+          str, _ = Haml::Shared.balance(@scanner, ?(, ?), 1)
+          [name, str]
+        else
+          [name, str{ss}, expr, tok!(/\)/)]
+        end
       end
 
       def interpolation

test/sass/scss/css_test.rb

@@ -332,6 +332,20 @@ foo {
 SCSS
   end
 
+  def test_expression_function
+    assert_parses <<SCSS
+foo {
+  a: 12px expression(1 + (3 / Foo.bar("baz" + "bang") + function() {return 12;}) % 12); }
+SCSS
+  end
+
+  def test_calc_function
+    assert_parses <<SCSS
+foo {
+  a: 12px calc(100%/3 - 2*1em - 2*1px); }
+SCSS
+  end
+
   ## Directives
 
   def test_charset_directive