toHaveNoOtherSpyInteractions implementation

src/core/CallTracker.js

@@ -125,6 +125,16 @@ getJasmineRequireObj().CallTracker = function(j$) {
     this.saveArgumentsByValue = function() {
       opts.cloneArgs = true;
     };
+
+    /**
+     * Get the number of unverified invocations of this spy.
+     * @name Spy#calls#unverifiedCount
+     * @function
+     * @return {Integer}
+     */
+    this.unverifiedCount = function() {
+      return calls.reduce((count, call) => count + (call.verified ? 0 : 1), 0);
+    };
   }
 
   return CallTracker;