diff --git a/lib/Internal/Producer.php b/lib/Internal/Producer.php
index fdd51b5..e1656c7 100644
--- a/lib/Internal/Producer.php
+++ b/lib/Internal/Producer.php
@@ -124,7 +124,6 @@ trait Producer {
         return $deferred->promise();
     }
 
-
     /**
      * Resolves the stream with the given value.
      *
diff --git a/lib/Loop/UvDriver.php b/lib/Loop/UvDriver.php
index 1be8001..01ba592 100644
--- a/lib/Loop/UvDriver.php
+++ b/lib/Loop/UvDriver.php
@@ -255,8 +255,8 @@ class UvDriver extends Driver {
                 unset($this->watchers[$eventId][$id]);
 
                 if (empty($this->watchers[$eventId])) {
-                    unset($this->watchers[$eventId]);
-                    unset($this->io[(int) $watcher->value]);
+                    unset($this->watchers[$eventId], $this->io[(int) $watcher->value]);
+
                     if (\uv_is_active($event)) {
                         \uv_poll_stop($event);
                     }
diff --git a/lib/functions.php b/lib/functions.php
index b90ca32..02954d2 100644
--- a/lib/functions.php
+++ b/lib/functions.php
@@ -74,8 +74,8 @@ namespace Amp {
 }
 
 namespace Amp\Promise {
-    use Amp\Loop;
     use Amp\Deferred;
+    use Amp\Loop;
     use Amp\MultiReasonException;
     use Amp\Promise;
     use Amp\Success;
@@ -474,12 +474,12 @@ namespace Amp\Promise {
 namespace Amp\Stream {
     use Amp\Coroutine;
     use Amp\Emitter;
-    use Amp\StreamIterator;
     use Amp\Loop;
     use Amp\Pause;
     use Amp\Producer;
     use Amp\Promise;
     use Amp\Stream;
+    use Amp\StreamIterator;
     use Amp\UnionTypeError;
 
     /**
diff --git a/test/AdaptTest.php b/test/AdaptTest.php
index c4b78a1..13c9e56 100644
--- a/test/AdaptTest.php
+++ b/test/AdaptTest.php
@@ -3,8 +3,8 @@
 namespace Amp\Test;
 
 use Amp\Failure;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 
 class PromiseMock {
     /** @var \Amp\Promise */
diff --git a/test/AllTest.php b/test/AllTest.php
index be8812c..6e1fcd7 100644
--- a/test/AllTest.php
+++ b/test/AllTest.php
@@ -2,10 +2,10 @@
 
 namespace Amp\Test;
 
+use Amp\Loop;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Success;
-use Amp\Loop;
 
 class AllTest extends \PHPUnit\Framework\TestCase {
     public function testEmptyArray() {
diff --git a/test/AnyTest.php b/test/AnyTest.php
index 765b65e..de7f5bc 100644
--- a/test/AnyTest.php
+++ b/test/AnyTest.php
@@ -3,10 +3,10 @@
 namespace Amp\Test;
 
 use Amp\Failure;
+use Amp\Loop;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Success;
-use Amp\Loop;
 
 class AnyTest extends \PHPUnit\Framework\TestCase {
     public function testEmptyArray() {
diff --git a/test/CallTest.php b/test/CallTest.php
index b5ae5cd..d7e09c5 100644
--- a/test/CallTest.php
+++ b/test/CallTest.php
@@ -4,8 +4,8 @@ namespace Amp\Test;
 
 use Amp;
 use Amp\Coroutine;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use PHPUnit\Framework\TestCase;
 use React\Promise\FulfilledPromise as FulfilledReactPromise;
 
diff --git a/test/CaptureTest.php b/test/CaptureTest.php
index a80809c..1641aa5 100644
--- a/test/CaptureTest.php
+++ b/test/CaptureTest.php
@@ -3,8 +3,8 @@
 namespace Amp\Test;
 
 use Amp\Failure;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use function React\Promise\reject;
 
 class CaptureTest extends \PHPUnit\Framework\TestCase {
diff --git a/test/CoroutineTest.php b/test/CoroutineTest.php
index 5b754f7..ff1dd1c 100644
--- a/test/CoroutineTest.php
+++ b/test/CoroutineTest.php
@@ -7,8 +7,8 @@ use Amp\Failure;
 use Amp\InvalidYieldError;
 use Amp\Loop;
 use Amp\Pause;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use PHPUnit\Framework\TestCase;
 use React\Promise\FulfilledPromise as FulfilledReactPromise;
 use React\Promise\Promise as ReactPromise;
diff --git a/test/FilterTest.php b/test/FilterTest.php
index 257cebf..e5e3859 100644
--- a/test/FilterTest.php
+++ b/test/FilterTest.php
@@ -2,10 +2,10 @@
 
 namespace Amp\Test;
 
-use Amp\Producer;
-use Amp\Stream;
 use Amp\Emitter;
 use Amp\Loop;
+use Amp\Producer;
+use Amp\Stream;
 
 class FilterTest extends \PHPUnit\Framework\TestCase {
     public function testNoValuesEmitted() {
diff --git a/test/FirstTest.php b/test/FirstTest.php
index 9d7e067..b6664a8 100644
--- a/test/FirstTest.php
+++ b/test/FirstTest.php
@@ -2,13 +2,12 @@
 
 namespace Amp\Test;
 
-use Amp;
 use Amp\Failure;
+use Amp\Loop;
 use Amp\MultiReasonException;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Success;
-use Amp\Loop;
 
 class FirstTest extends \PHPUnit\Framework\TestCase {
     /**
diff --git a/test/LazyPromiseTest.php b/test/LazyPromiseTest.php
index 00d1fe5..dd36d10 100644
--- a/test/LazyPromiseTest.php
+++ b/test/LazyPromiseTest.php
@@ -2,7 +2,6 @@
 
 namespace Amp\Test;
 
-use Amp;
 use Amp\Failure;
 use Amp\LazyPromise;
 use Amp\Success;
diff --git a/test/Loop/DriverTest.php b/test/Loop/DriverTest.php
index 24a9f88..8ab8800 100644
--- a/test/Loop/DriverTest.php
+++ b/test/Loop/DriverTest.php
@@ -8,7 +8,6 @@ use Amp\Loop;
 use Amp\Loop\Driver;
 use Amp\Loop\InvalidWatcherError;
 use Amp\Loop\UnsupportedFeatureException;
-use Amp\Success;
 use PHPUnit\Framework\TestCase;
 use React\Promise\RejectedPromise as RejectedReactPromise;
 
@@ -231,7 +230,6 @@ abstract class DriverTest extends TestCase {
         });
     }
 
-
     function provideRegistrationArgs() {
         $args = [
             ["defer", [function () {
diff --git a/test/MapTest.php b/test/MapTest.php
index 90e2e3f..be71777 100644
--- a/test/MapTest.php
+++ b/test/MapTest.php
@@ -2,11 +2,10 @@
 
 namespace Amp\Test;
 
-use Amp;
-use Amp\Producer;
-use Amp\Stream;
 use Amp\Emitter;
 use Amp\Loop;
+use Amp\Producer;
+use Amp\Stream;
 
 class MapTest extends \PHPUnit\Framework\TestCase {
     public function testNoValuesEmitted() {
diff --git a/test/PauseTest.php b/test/PauseTest.php
index 042a94d..363954f 100644
--- a/test/PauseTest.php
+++ b/test/PauseTest.php
@@ -2,8 +2,8 @@
 
 namespace Amp\Test;
 
-use Amp\Pause;
 use Amp\Loop;
+use Amp\Pause;
 
 class PauseTest extends \PHPUnit\Framework\TestCase {
     public function testPause() {
diff --git a/test/PipeTest.php b/test/PipeTest.php
index 4f83d05..88b6f9a 100644
--- a/test/PipeTest.php
+++ b/test/PipeTest.php
@@ -3,8 +3,8 @@
 namespace Amp\Test;
 
 use Amp\Failure;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use function React\Promise\resolve;
 
 class PipeTest extends \PHPUnit\Framework\TestCase {
diff --git a/test/ProducerTest.php b/test/ProducerTest.php
index 228a437..20da971 100644
--- a/test/ProducerTest.php
+++ b/test/ProducerTest.php
@@ -4,9 +4,9 @@ namespace Amp\Test;
 
 use Amp;
 use Amp\Deferred;
-use Amp\Producer;
-use Amp\Pause;
 use Amp\Loop;
+use Amp\Pause;
+use Amp\Producer;
 use PHPUnit\Framework\TestCase;
 use React\Promise\Promise as ReactPromise;
 
diff --git a/test/ProducerTraitTest.php b/test/ProducerTraitTest.php
index 6166f4f..e9ac6dd 100644
--- a/test/ProducerTraitTest.php
+++ b/test/ProducerTraitTest.php
@@ -5,8 +5,8 @@ namespace Amp\Test;
 use Amp\Deferred;
 use Amp\Failure;
 use Amp\Loop;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use PHPUnit\Framework\TestCase;
 use React\Promise\FulfilledPromise as FulfilledReactPromise;
 
diff --git a/test/SomeTest.php b/test/SomeTest.php
index e822bac..612d06b 100644
--- a/test/SomeTest.php
+++ b/test/SomeTest.php
@@ -3,11 +3,11 @@
 namespace Amp\Test;
 
 use Amp\Failure;
+use Amp\Loop;
 use Amp\MultiReasonException;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Success;
-use Amp\Loop;
 
 class SomeTest extends \PHPUnit\Framework\TestCase {
     public function testEmptyArray() {
diff --git a/test/StreamFromIterableTest.php b/test/StreamFromIterableTest.php
index b2ec20f..7d39dc2 100644
--- a/test/StreamFromIterableTest.php
+++ b/test/StreamFromIterableTest.php
@@ -3,11 +3,11 @@
 namespace Amp\Test;
 
 use Amp\Failure;
+use Amp\Loop;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Stream;
 use Amp\Success;
-use Amp\Loop;
 
 class StreamFromIterableTest extends \PHPUnit\Framework\TestCase {
     const TIMEOUT = 10;
diff --git a/test/StreamIteratorTest.php b/test/StreamIteratorTest.php
index f096fdf..fbfe952 100644
--- a/test/StreamIteratorTest.php
+++ b/test/StreamIteratorTest.php
@@ -2,12 +2,11 @@
 
 namespace Amp\Test;
 
-use Amp;
-use Amp\Producer;
-use Amp\StreamIterator;
-use Amp\Pause;
 use Amp\Emitter;
 use Amp\Loop;
+use Amp\Pause;
+use Amp\Producer;
+use Amp\StreamIterator;
 use PHPUnit\Framework\TestCase;
 
 class StreamIteratorTest extends TestCase {
diff --git a/test/SuccessTest.php b/test/SuccessTest.php
index 3e65826..f8b46f8 100644
--- a/test/SuccessTest.php
+++ b/test/SuccessTest.php
@@ -3,8 +3,8 @@
 namespace Amp\Test;
 
 use Amp\Loop;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use React\Promise\RejectedPromise as RejectedReactPromise;
 
 class SuccessTest extends \PHPUnit\Framework\TestCase {
diff --git a/test/TimeoutTest.php b/test/TimeoutTest.php
index 12c91de..153fe4a 100644
--- a/test/TimeoutTest.php
+++ b/test/TimeoutTest.php
@@ -5,8 +5,8 @@ namespace Amp\Test;
 use Amp\Failure;
 use Amp\Loop;
 use Amp\Pause;
-use Amp\Success;
 use Amp\Promise;
+use Amp\Success;
 use function React\Promise\resolve;
 
 class TimeoutTest extends \PHPUnit\Framework\TestCase {
diff --git a/test/WaitTest.php b/test/WaitTest.php
index 39915a2..62d9d48 100644
--- a/test/WaitTest.php
+++ b/test/WaitTest.php
@@ -4,10 +4,10 @@ namespace Amp\Test;
 
 use Amp\Deferred;
 use Amp\Failure;
+use Amp\Loop;
 use Amp\Pause;
 use Amp\Promise;
 use Amp\Success;
-use Amp\Loop;
 use PHPUnit\Framework\TestCase;
 use function React\Promise\resolve;