diff --git a/addon/@ember/test-waiters/build-waiter.ts b/addon/@ember/test-waiters/build-waiter.ts
index 4d26c502..613056c7 100644
--- a/addon/@ember/test-waiters/build-waiter.ts
+++ b/addon/@ember/test-waiters/build-waiter.ts
@@ -89,9 +89,11 @@ class TestWaiterImpl<T extends object | Primitive = Token> implements TestWaiter
   private _getCompletedOperations(token: T) {
     let type = typeof token;
 
-    return token !== null || (type !== 'function' && type !== 'object')
-      ? this.completedOperationsForPrimitives
-      : this.completedOperationsForTokens;
+    let isFunction = type === 'function';
+    let isObject = token !== null && type === 'object';
+    let isPrimitive = !isFunction && !isObject;
+
+    return isPrimitive ? this.completedOperationsForPrimitives : this.completedOperationsForTokens;
   }
 }
 
diff --git a/tests/unit/build-waiter-test.ts b/tests/unit/build-waiter-test.ts
index 5b176bcb..4e7816ca 100644
--- a/tests/unit/build-waiter-test.ts
+++ b/tests/unit/build-waiter-test.ts
@@ -276,4 +276,16 @@ module('build-waiter', function(hooks) {
 
     assert.equal((waiter as any).items.size, 0);
   });
+
+  test('completed operations tracking does not leak non-primitive tokens', function(assert) {
+    let waiter = buildWaiter('@ember/test-waiters:my-waiter');
+
+    const tokens = [undefined, {}, function() {}, Promise.resolve()];
+
+    for (let token of tokens) {
+      waiter.endAsync(waiter.beginAsync(token));
+    }
+
+    assert.equal((waiter as any).completedOperationsForPrimitives.size, 0);
+  });
 });