fix(overmind): ensure flush callbacks are run even though disposing

Author: christianalfoni

packages/node_modules/proxy-state-tree/src/index.ts

@@ -192,8 +192,16 @@ export class ProxyStateTree<T extends object> implements IProxyStateTree<T> {
       callback(changes.mutations, sortedPaths, flushId, isAsync)
     }
 
-    for (let callback of this.flushCallbacks) {
-      callback(changes.mutations, sortedPaths, flushId, isAsync)
+    // We have to ensure that we iterate all callbacks. One flush might
+    // lead to a change of the array (disposing), which means something
+    // might be skipped. But we still want to allow removal of callbacks,
+    // we just do not want to skip any, which is why we still check if it
+    // exists in the original array
+    const flushCallbacks = this.flushCallbacks.slice()
+    for (let callback of flushCallbacks) {
+      if (this.flushCallbacks.includes(callback)) {
+        callback(changes.mutations, sortedPaths, flushId, isAsync)
+      }
     }
 
     paths.clear()