Add noop plugin as detached plugin (#2824)

packages/slate-react/src/plugins/debug/noop.js

@@ -0,0 +1,45 @@
+import EVENT_HANDLERS from '../../constants/event-handlers'
+
+/**
+ * This plugin prevents events from going any further and is useful in dev.
+ *
+ * The purpose is to see how the editor events and mutations behave without
+ * the noise of the editor also adding its own events and mutations.
+ *
+ * IMPORTANT:
+ *
+ * This plugin is detached (i.e. there is no way to turn it on in Slate).
+ * You must hard code it into `plugins/react/index`.
+ *
+ * @return {Object}
+ */
+
+function NoopPlugin() {
+  /**
+   * Plugin Object
+   *
+   * @type {Object}
+   */
+
+  const plugin = {}
+
+  for (const eventName of EVENT_HANDLERS) {
+    plugin[eventName] = function(event, editor, next) {}
+  }
+
+  /**
+   * Return the plugin.
+   *
+   * @type {Object}
+   */
+
+  return plugin
+}
+
+/**
+ * Export.
+ *
+ * @type {Function}
+ */
+
+export default NoopPlugin