Don't make style names that start with -

Can happen under advanced compilation if the fn's name starts with _

src/spade/util.cljc

@@ -4,7 +4,8 @@
 (defn factory->name [factory]
   (-> (.-name factory)
       (str/replace "_factory$" "")
-      (str/replace #"[_$]" "-")))
+      (str/replace #"[_$]" "-")
+      (str/replace #"^-" "_")))
 
 (defn sanitize [s]
   (-> s

test/spade/runner.cljs

@@ -1,5 +1,6 @@
 (ns spade.runner
-  (:require [doo.runner :refer-macros [doo-tests doo-all-tests]]
-            [spade.core-test]))
+  (:require [doo.runner :refer-macros [doo-all-tests]]
+            [spade.core-test]
+            [spade.util-test]))
 
 (doo-all-tests #"spade\..*-test")

test/spade/util_test.cljs

@@ -0,0 +1,11 @@
+(ns spade.util-test
+  (:require [cljs.test :refer-macros [deftest testing is]]
+            [spade.util :refer [factory->name]]))
+
+(deftest factory->name-test
+  (testing "Never prefix with illegal characters"
+    ; simulate a fn under advanced compilation having
+    ; a name that starts with _
+    (is (= "_advanced-compile"
+           (factory->name #js {:name "_advanced_compile"})))))
+