Improve state scope check, see #193

phetsims · Aug 18, 2020 · 4b92a38 · 4b92a38
1 parent a8574eb
commit 4b92a38
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/js/Tandem.js b/js/Tandem.js
@@ -164,6 +164,16 @@ class Tandem {
     }
   }
 
+  /**
+   * Returns true if this Tandem has the specified ancestor Tandem.
+   * @param ancestor
+   * @returns {boolean}
+   * @public
+   */
+  hasAncestor( ancestor ) {
+    return this.parentTandem === ancestor || ( this.parentTandem && this.parentTandem.hasAncestor( ancestor ) );
+  }
+
   /**
    * Removes a PhetioObject and signifies to listeners that it has been removed.
    * @param {PhetioObject} phetioObject