Check for iterator initialization

src/Observable/Exception/UninitializedError.php

@@ -0,0 +1,12 @@
+<?php
+
+/*
+ * This file is part of Icicle, a library for writing asynchronous code in PHP using promises and coroutines.
+ *
+ * @copyright 2014-2015 Aaron Piotrowski. All rights reserved.
+ * @license MIT See the LICENSE file that was distributed with this source code for more information.
+ */
+
+namespace Icicle\Observable\Exception;
+
+class UninitializedError extends Error {}

src/Observable/Internal/Placeholder.php

@@ -50,7 +50,6 @@ public function __construct(PromiseInterface $promise, $backPressure)
     public function getPromise()
     {
         ++$this->waiting;
-
         return $this->promise;
     }
 

src/Observable/ObservableIterator.php

@@ -12,6 +12,7 @@
 use Exception;
 use Icicle\Observable\Exception\CompletedError;
 use Icicle\Observable\Exception\SynchronousIterationError;
+use Icicle\Observable\Exception\UninitializedError;
 use Icicle\Promise;
 
 class ObservableIterator implements ObservableIteratorInterface
@@ -59,9 +60,9 @@ public function __destruct()
      */
     public function wait()
     {
-        if (null !== $this->promise && $this->promise->isPending()) {
+        if (null !== $this->promise) {
             throw new SynchronousIterationError(
-                'The returned promise should be resolved before calling this method again.'
+                'The coroutine created from this method should be resolved before calling this method again.'
             );
         }
 
@@ -100,6 +101,10 @@ public function getCurrent()
             throw new CompletedError('The observable has completed and the iterator is invalid.');
         }
 
+        if (null === $this->placeholder) {
+            throw new UninitializedError('wait() must be called before calling this method.');
+        }
+
         return $this->current;
     }