initial commit

app/javascript/elements/files_list.js

@@ -0,0 +1,16 @@
+import { actionable } from '@github/catalyst/lib/actionable'
+import { targets, targetable } from '@github/catalyst/lib/targetable'
+
+export default actionable(targetable(class extends HTMLElement {
+  static [targets.static] = [
+    'items'
+  ]
+
+  add (e) {
+    const elem = document.createElement('input')
+    elem.value = e.detail.uuid
+    elem.name = `values[${this.dataset.fieldUuid}][]`
+
+    this.prepend(elem)
+  }
+}))