Adding a new (passing) test case to check comment preservation and removal.

spec/basic/06_nesting_and_comments/input.scss

+$blah: bloo blee;
+$blip: "a 'red' and \"blue\" value";
+
+/* top level comment -- should be preserved */
+div {
+  /* another comment that should be preserved */
+  color: red;
+  background: blue;
+  $blux: hux; // gone!
+  span {
+    font-weight: bold;
+    a {
+      text-decoration: none; /* where will this comment go? */
+      color: green;
+      /* what about this comment? */ border: 1px $blah red;
+    }
+    /* yet another comment that should be preserved */
+    display: inline-block;
+  }  // gone!
+  /* the next selector should be indented two spaces */
+  empty {
+    not_empty {
+      blah: blah; // gone!
+      bloo: bloo;
+    }
+  }
+  p {
+    padding: 10px 8%;
+    -webkit-box-sizing: $blux;
+  }
+  margin: 10px 5px;
+  h1 {
+    color: $blip;
+  }
+}
+/* last comment, top level again --
+   compare the indentation! */
+   
+div {
+  f: g;
+  empty {
+    span {
+      a: b;
+    }
+  }
+  empty_with_comment {
+    /* hey now */
+    span {
+      c: d;
+    }
+  }
+}
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spec/basic/06_nesting_and_comments/output.css

+/* top level comment -- should be preserved */
+div {
+  /* another comment that should be preserved */
+  color: red;
+  background: blue;
+  /* the next selector should be indented two spaces */
+  margin: 10px 5px; }
+  div span {
+    font-weight: bold;
+    /* yet another comment that should be preserved */
+    display: inline-block; }
+    div span a {
+      text-decoration: none;
+      /* where will this comment go? */
+      color: green;
+      /* what about this comment? */
+      border: 1px bloo blee red; }
+  div empty not_empty {
+    blah: blah;
+    bloo: bloo; }
+  div p {
+    padding: 10px 8%;
+    -webkit-box-sizing: hux; }
+  div h1 {
+    color: "a 'red' and \"blue\" value"; }
+
+/* last comment, top level again --
+   compare the indentation! */
+div {
+  f: g; }
+  div empty span {
+    a: b; }
+  div empty_with_comment {
+    /* hey now */ }
+    div empty_with_comment span {
+      c: d; }

test.scss

@@ -10,10 +10,9 @@ div {
   span {
     font-weight: bold;
     a {
-      text-decoration: none;
+      text-decoration: none; /* where will this comment go? */
       color: green;
-      content: "▲";
-      border: 1px $blah red;
+      /* what about this comment? */ border: 1px $blah red;
     }
     /* yet another comment that should be preserved */
     display: inline-block;
@@ -44,4 +43,10 @@ div {
       a: b;
     }
   }
+  empty_with_comment {
+    /* hey now */
+    span {
+      c: d;
+    }
+  }
 }
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