Throw InvalidArgumentException for invalid canceller

Author: clue

src/React/Promise/Deferred.php

@@ -16,6 +16,15 @@ class Deferred implements PromiseInterface, ResolverInterface, PromisorInterface
 
     public function __construct($canceller = null)
     {
+        if ($canceller !== null && !is_callable($canceller)) {
+            throw new \InvalidArgumentException(
+                sprintf(
+                    'The canceller argument must be null or of type callable, %s given.',
+                    gettype($canceller)
+                )
+            );
+        }
+
         $this->canceller = $canceller;
     }
 

tests/React/Promise/DeferredTest.php

@@ -201,4 +201,13 @@ public function shouldInvokeCancellationHandleWhenCancellingAllDerived()
         $p1->cancel();
         $p2->cancel();
     }
+
+    /**
+     * @test
+     * @expectedException InvalidArgumentException
+     */
+    public function shouldThrowIfCancellerIsNotACallable()
+    {
+        new Deferred(false);
+    }
 }

tests/React/Promise/PromiseTest.php

@@ -90,4 +90,13 @@ public function shouldInvokeCancellationHandlerAndStayPendingWhenCallingCancel()
 
         $promise->then($this->expectCallableNever(), $this->expectCallableNever());
     }
+
+    /**
+     * @test
+     * @expectedException InvalidArgumentException
+     */
+    public function shouldThrowIfCancellerIsNotACallable()
+    {
+        new Promise(function () { }, false);
+    }
 }