Dynamic vars support

core/src/main.js

@@ -67,11 +67,9 @@ class Comms {
         BDIpc.on('bd-compileSass', o => {
             const { scss, path } = o.args;
             if (!scss && !path) return;
+            const data = scss ? `${scss} @import '${path}';` : `@import '${path}';`;
 
-            sass.render({
-                file: path,
-                data: scss
-            }, (err, result) => {
+            sass.render({ data }, (err, result) => {
                 if (err) {
                     o.reply({ err });
                     return;

tests/themes/Example/index.scss

@@ -5,5 +5,5 @@ div {
 }
 
 span {
-    border: 1px solid brown;
+    border: 1px solid rgba(20, 20, 20, $spanOpacity);
 }

tests/themes/Example/vars.scss

@@ -1 +1,2 @@
-$divBg: green;
+$divBg: green !default;
+$spanOpacity: 0.5 !default;