Additional tests to avoid future garbage cycle regressions

Author: clue

tests/DeferredTest.php

@@ -76,4 +76,37 @@ public function shouldRejectWithoutCreatingGarbageCyclesIfCancellerHoldsReferenc
 
         $this->assertSame(0, gc_collect_cycles());
     }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToPendingDeferred()
+    {
+        gc_collect_cycles();
+        $deferred = new Deferred();
+        $deferred->promise();
+        unset($deferred);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToPendingDeferredWithUnusedCanceller()
+    {
+        gc_collect_cycles();
+        $deferred = new Deferred(function () { });
+        $deferred->promise();
+        unset($deferred);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToPendingDeferredWithNoopCanceller()
+    {
+        gc_collect_cycles();
+        $deferred = new Deferred(function () { });
+        $deferred->promise()->cancel();
+        unset($deferred);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
 }

tests/FulfilledPromiseTest.php

@@ -47,4 +47,30 @@ public function shouldThrowExceptionIfConstructedWithAPromise()
 
         return new FulfilledPromise(new FulfilledPromise());
     }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToFulfilledPromiseWithAlwaysFollowers()
+    {
+        gc_collect_cycles();
+        $promise = new FulfilledPromise(1);
+        $promise->always(function () {
+            throw new \RuntimeException();
+        });
+        unset($promise);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToFulfilledPromiseWithThenFollowers()
+    {
+        gc_collect_cycles();
+        $promise = new FulfilledPromise(1);
+        $promise = $promise->then(function () {
+            throw new \RuntimeException();
+        });
+        unset($promise);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
 }

tests/RejectedPromiseTest.php

@@ -47,4 +47,30 @@ public function shouldThrowExceptionIfConstructedWithAPromise()
 
         return new RejectedPromise(new RejectedPromise());
     }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToRejectedPromiseWithAlwaysFollowers()
+    {
+        gc_collect_cycles();
+        $promise = new RejectedPromise(1);
+        $promise->always(function () {
+            throw new \RuntimeException();
+        });
+        unset($promise);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
+
+    /** @test */
+    public function shouldNotLeaveGarbageCyclesWhenRemovingLastReferenceToRejectedPromiseWithThenFollowers()
+    {
+        gc_collect_cycles();
+        $promise = new RejectedPromise(1);
+        $promise = $promise->then(null, function () {
+            throw new \RuntimeException();
+        });
+        unset($promise);
+
+        $this->assertSame(0, gc_collect_cycles());
+    }
 }