Add PHPStan to test environment

Author: clue

.gitattributes

@@ -1,6 +1,7 @@
 /.gitattributes export-ignore
 /.github/ export-ignore
 /.gitignore export-ignore
+/phpstan.neon.dist export-ignore
 /phpunit.xml.dist export-ignore
 /phpunit.xml.legacy export-ignore
 /tests/ export-ignore

.github/workflows/ci.yml

@@ -30,3 +30,25 @@ jobs:
         if: ${{ matrix.php >= 7.3 }}
       - run: vendor/bin/phpunit --coverage-text -c phpunit.xml.legacy
         if: ${{ matrix.php < 7.3 }}
+
+  PHPStan:
+    name: PHPStan (PHP ${{ matrix.php }})
+    runs-on: ubuntu-22.04
+    strategy:
+      matrix:
+        php:
+          - 8.2
+          - 8.1
+          - 8.0
+          - 7.4
+          - 7.3
+          - 7.2
+          - 7.1
+    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

@@ -426,6 +426,12 @@ 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 || 1.4.10",
         "phpunit/phpunit": "^9.5 || ^7.5"
     },
     "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

@@ -294,7 +294,7 @@ 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
@@ -437,9 +437,9 @@ 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/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);

tests/SeriesTest.php

@@ -185,6 +185,7 @@ function () use (&$cancelled) {
         );
 
         $promise = React\Async\series($tasks);
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $this->assertSame(1, $cancelled);

tests/WaterfallTest.php

@@ -199,6 +199,7 @@ function () use (&$cancelled) {
         );
 
         $promise = React\Async\waterfall($tasks);
+        assert(method_exists($promise, 'cancel'));
         $promise->cancel();
 
         $this->assertSame(1, $cancelled);