don't prefix if selector *starts with* :root

also, update to work with comma-separated selectors

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

Author: ahdinosaur

index.js

@@ -7,8 +7,11 @@ function postcssPrefix (prefix, options) {
 
   return function (root) {
     root.walkRules(function (rule) {
-      if (rule.selector === ':root') return
-      rule.selector = prefix + rule.selector
+      rule.selectors = rule.selectors.map(function (selector) {
+        if (rule.selector.indexOf(':root') === 0) return selector
+        return prefix + selector
+      })
+      rule.selector = rule.selectors.join(', ')
     })
   }
 }

test/fixture-out.css

@@ -1,8 +1,15 @@
 :root {
   --color-red: #f00;
+}
+
+:root a {
   --color-blue: #00f;
 }
 
+:root ul, :root li {
+  --color-green: #0f0;
+}
+
 #hello-world h1 {}
 #hello-world h1.title {}
 #hello-world h2#thing {}

test/fixture.css

@@ -1,8 +1,15 @@
 :root {
   --color-red: #f00;
+}
+
+:root a {
   --color-blue: #00f;
 }
 
+:root ul, :root li {
+  --color-green: #0f0;
+}
+
 h1 {}
 h1.title {}
 h2#thing {}