Add maximum number of recursivity for normalization

src/transforms/normalize.js

@@ -1,6 +1,9 @@
 import warning from '../utils/warning'
 import { default as defaultSchema } from '../plugins/schema'
 
+// Maximum recursive calls for normalization
+const MAX_CALLS = 50
+
 /**
  * Refresh a reference to a node that have been modified in a transform.
  * @param  {Transform} transform
@@ -82,7 +85,15 @@ function _normalizeNodeWith(transform, schema, node) {
  */
 
 export function normalizeNodeWith(transform, schema, node) {
-  // console.log(`normalize node key=${node.key}`)
+  let recursiveCount = 0
+
+  // Auxiliary function, called recursively, with a maximum calls safety net.
+  function _recur() {
+    recursiveCount++
+    if (recursiveCount > MAX_CALLS) {
+      warning('Unexpected number of successive normalizations. Aborting.')
+      return transform
+    }
     // Iterate over its children
     transform = _normalizeChildrenWith(transform, schema, node)
 
@@ -95,6 +106,9 @@ export function normalizeNodeWith(transform, schema, node) {
     return transform
   }
 
+  return _recur(transform, schema, node)
+}
+
 /**
  * Normalize a node its parents using a schema.
  *