Index: src/UploadTest.vue
===================================================================
--- src/UploadTest.vue	(revision 64249d67d46154f425d75b148c215f53466b90e0)
+++ src/UploadTest.vue	(revision d45005e5b50b98b5f612846d824b31699c9366b4)
@@ -31,4 +31,8 @@
 const abort = (): void => {
   (inst as any).refs.uploader.abort()
+}
+
+const log = (code: string, args: any[]) => {
+  console.log.apply(null, ['>', code].concat(args))
 }
 
@@ -59,5 +63,6 @@
                @update:canStart='(flag: boolean) => can_start = flag'
                @update:canAbort='(flag: boolean) => can_abort = flag'
-               @update:canReset='(flag: boolean) => can_reset = flag'>
+               @update:canReset='(flag: boolean) => can_reset = flag'
+               @debug='(code: string, args: any[]) => log(code, args)'>
       <template #idle='{ pick }'>
         <div class='idle'>