Handling selectors that begin with a combinator, since nesting makes them valid and meaningful.

document_parser.cpp

@@ -48,6 +48,11 @@ namespace Sass {
   Node Document::parse_selector()
   {
     Node selector(line_number, Node::selector, 1);
+    if (lex< exactly<'+'> >() ||
+        lex< exactly<'~'> >() ||
+        lex< exactly<'>'> >()) {
+      selector << Node(line_number, Node::selector_combinator, lexed);
+    }
     selector << parse_simple_selector_sequence();
     while (lex< exactly<'+'> >() ||
            lex< exactly<'~'> >() ||

node.hpp

@@ -121,7 +121,13 @@ namespace Sass {
     
     operator string() {
       if (type == selector) {
-        string result(string(children->at(0)));
+        string result;
+        if (children->at(0).type == selector_combinator) {
+          result += string(children->at(0).token) + ' ';
+        }
+        else {
+          result += string(children->at(0));
+        }
         for (int i = 1; i < children->size(); ++i) {
           result += string(children->at(i));
         }
@@ -131,6 +137,9 @@ namespace Sass {
         if (std::isspace(token.begin[0])) return string(" ");
         else return string(" ") += string(token) += string(" ");
       }
+      // else if (type == simple_selector_sequence) {
+      //   return string(" ") += string(token);
+      // }
       else {
         return string(token);
       }

selector_groups_and_combinators.scss

+a + b, c {
+  blah: blah;
+  bleh: bleh;
+  d e, f ~ g + h, > i {
+    bloo: bloo;
+    blee: blee;
+  }
+}
\ No newline at end of file

spec/basic/09_selector_groups_and_combinators/input.scss

 a + b, c {
   blah: blah;
   bleh: bleh;
-  d e, f ~ g + h {
+  d e, f ~ g + h, > i {
     bloo: bloo;
     blee: blee;
   }

spec/basic/09_selector_groups_and_combinators/output.css

 a + b, c {
   blah: blah;
   bleh: bleh; }
-  a + b d e, a + b f ~ g + h, c d e, c f ~ g + h {
+  a + b d e, a + b f ~ g + h, a + b > i, c d e, c f ~ g + h, c > i {
     bloo: bloo;
     blee: blee; }