remove unwrap from variable value parsing

src/parse/variable.rs

@@ -123,7 +123,9 @@ impl<'a> Parser<'a> {
                         }
                         Some(..) | None => {}
                     }
-                    val_toks.push(self.toks.next().unwrap());
+                    if let Some(tok) = self.toks.next() {
+                        val_toks.push(tok);
+                    }
                 }
                 '{' => break,
                 '}' => {

tests/variables.rs

@@ -143,3 +143,7 @@ error!(
     invalid_escape,
     "$\\110000: red;", "Error: Invalid escape sequence."
 );
+error!(
+    nothing_after_hash_in_variable_decl,
+    "$color: #", "Error: Expected identifier."
+);