add test case for #2

Signed-off-by: Yoshua Wuyts <i@yoshuawuyts.com>

Author: ahdinosaur

test/fixture-out.css

@@ -10,6 +10,9 @@
   --color-green: #0f0;
 }
 
+#hello-world { color: green; }
+#hello-world:hover { color: blue; }
+
 #hello-world h1 {}
 #hello-world h1.title {}
 #hello-world h2#thing {}

test/fixture.css

@@ -10,6 +10,9 @@
   --color-green: #0f0;
 }
 
+:host { color: green; }
+:host(:hover) { color: blue; }
+
 h1 {}
 h1.title {}
 h2#thing {}