Add PHPStan to test environment

Author: clue

.gitattributes

@@ -1,5 +1,6 @@
 /.gitattributes export-ignore
 /.github/ export-ignore
 /.gitignore export-ignore
+/phpstan.neon.dist export-ignore
 /phpunit.xml.dist export-ignore
 /tests/ export-ignore

.github/workflows/ci.yml

@@ -22,3 +22,20 @@ jobs:
           ini-file: development
       - run: composer install
       - run: vendor/bin/phpunit --coverage-text
+
+  PHPStan:
+    name: PHPStan (PHP ${{ matrix.php }})
+    runs-on: ubuntu-22.04
+    strategy:
+      matrix:
+        php:
+          - 8.2
+          - 8.1
+    steps:
+      - uses: actions/checkout@v3
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          coverage: none
+      - run: composer install
+      - run: vendor/bin/phpstan

README.md

@@ -659,6 +659,12 @@ To run the test suite, go to the project root and run:
 vendor/bin/phpunit
 ```
 
+On top of this, we use PHPStan on level 3 to ensure type safety across the project:
+
+```bash
+vendor/bin/phpstan
+```
+
 ## License
 
 MIT, see [LICENSE file](LICENSE).

composer.json

@@ -31,6 +31,7 @@
         "react/promise": "^3.0 || ^2.8 || ^1.2.1"
     },
     "require-dev": {
+        "phpstan/phpstan": "1.10.18",
         "phpunit/phpunit": "^9.5"
     },
     "autoload": {

phpstan.neon.dist

@@ -0,0 +1,11 @@
+parameters:
+    level: 3
+
+    paths:
+        - src/
+        - tests/
+
+    reportUnmatchedIgnoredErrors: false
+    ignoreErrors:
+        # ignore generic usage like `PromiseInterface<T>` until fixed upstream
+        - '/^PHPDoc .* contains generic type React\\Promise\\PromiseInterface<.+> but interface React\\Promise\\PromiseInterface is not generic\.$/'

src/functions.php

@@ -177,7 +177,7 @@
  * ```
  *
  * @param callable(mixed ...$args):mixed $function
- * @return callable(): PromiseInterface<mixed>
+ * @return callable(mixed ...$args): PromiseInterface<mixed>
  * @since 4.0.0
  * @see coroutine()
  */
@@ -587,7 +587,7 @@ function delay(float $seconds): void
  * });
  * ```
  *
- * @param callable(...$args):\Generator<mixed,PromiseInterface,mixed,mixed> $function
+ * @param callable(mixed ...$args):\Generator<mixed,PromiseInterface,mixed,mixed> $function
  * @param mixed ...$args Optional list of additional arguments that will be passed to the given `$function` as is
  * @return PromiseInterface<mixed>
  * @since 3.0.0
@@ -730,9 +730,9 @@ function series(iterable $tasks): PromiseInterface
         assert($tasks instanceof \Iterator);
     }
 
-    /** @var callable():void $next */
     $taskCallback = function ($result) use (&$results, &$next) {
         $results[] = $result;
+        assert($next instanceof \Closure);
         $next();
     };
 

tests/AsyncTest.php

@@ -194,6 +194,7 @@ public function testCancelAsyncWillReturnRejectedPromiseWhenCancellingPendingPro
             }));
         })();
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then(null, $this->expectCallableOnceWith(new \RuntimeException('Operation cancelled')));
@@ -211,6 +212,7 @@ public function testCancelAsyncWillReturnFulfilledPromiseWhenCancellingPendingPr
             }
         })();
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then($this->expectCallableOnceWith(42));
@@ -230,6 +232,7 @@ public function testCancelAsycWillReturnPendigPromiseWhenCancellingFirstPromiseR
             }
         })();
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then($this->expectCallableNever(), $this->expectCallableNever());
@@ -259,6 +262,7 @@ public function testCancelAsyncWillCancelNestedAwait()
             return time();
         })();
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
         await($promise);
     }

tests/AwaitTest.php

@@ -361,7 +361,7 @@ public function testNestedAwaits(callable $await)
             $resolve($await(new Promise(function ($resolve) use ($await) {
                 $resolve($await(new Promise(function ($resolve) use ($await) {
                     $resolve($await(new Promise(function ($resolve) use ($await) {
-                        $resolve($await(new Promise(function ($resolve) use ($await) {
+                        $resolve($await(new Promise(function ($resolve) {
                             Loop::addTimer(0.01, function () use ($resolve) {
                                 $resolve(true);
                             });

tests/CoroutineTest.php

@@ -114,6 +114,7 @@ public function testCancelCoroutineWillReturnRejectedPromiseWhenCancellingPendin
             });
         });
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then(null, $this->expectCallableOnceWith(new \RuntimeException('Operation cancelled')));
@@ -131,6 +132,7 @@ public function testCancelCoroutineWillReturnFulfilledPromiseWhenCancellingPendi
             }
         });
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then($this->expectCallableOnceWith(42));
@@ -150,6 +152,7 @@ public function testCancelCoroutineWillReturnPendigPromiseWhenCancellingFirstPro
             }
         });
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $promise->then($this->expectCallableNever(), $this->expectCallableNever());
@@ -209,6 +212,7 @@ public function testCoroutineShouldNotCreateAnyGarbageReferencesForPromiseReject
             });
         });
 
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
         unset($promise);
 

tests/ParallelTest.php

@@ -193,6 +193,7 @@ function () use (&$cancelled) {
         );
 
         $promise = React\Async\parallel($tasks);
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $this->assertSame(2, $cancelled);