Add psalm

Author: kelunik

.github/workflows/ci.yml

@@ -64,6 +64,9 @@ jobs:
       - name: Run tests
         run: vendor/bin/phpunit ${{ matrix.phpunit-flags }}
 
+      - name: Run static analysis
+        run: vendor/bin/psalm.phar
+
       - name: Run style fixer
         env:
           PHP_CS_FIXER_IGNORE_ENV: 1

composer.json

@@ -19,7 +19,8 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^9",
-        "amphp/php-cs-fixer-config": "^2-dev"
+        "amphp/php-cs-fixer-config": "^2-dev",
+        "psalm/phar": "^4.24"
     },
     "autoload": {
         "psr-4": {

psalm.xml

@@ -0,0 +1,51 @@
+<?xml version="1.0"?>
+<psalm
+        errorLevel="2"
+        resolveFromConfigFile="true"
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xmlns="https://getpsalm.org/schema/config"
+        xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+>
+    <projectFiles>
+        <directory name="examples"/>
+        <directory name="src"/>
+        <ignoreFiles>
+            <directory name="vendor"/>
+        </ignoreFiles>
+    </projectFiles>
+
+    <issueHandlers>
+        <StringIncrement>
+            <errorLevel type="suppress">
+                <directory name="examples"/>
+                <directory name="src"/>
+            </errorLevel>
+        </StringIncrement>
+
+        <RedundantConditionGivenDocblockType>
+            <errorLevel type="suppress">
+                <directory name="src"/>
+            </errorLevel>
+        </RedundantConditionGivenDocblockType>
+
+        <DocblockTypeContradiction>
+            <errorLevel type="suppress">
+                <directory name="src"/>
+            </errorLevel>
+        </DocblockTypeContradiction>
+
+        <MissingClosureParamType>
+            <errorLevel type="suppress">
+                <directory name="examples"/>
+                <directory name="src"/>
+            </errorLevel>
+        </MissingClosureParamType>
+
+        <MissingClosureReturnType>
+            <errorLevel type="suppress">
+                <directory name="examples"/>
+                <directory name="src"/>
+            </errorLevel>
+        </MissingClosureReturnType>
+    </issueHandlers>
+</psalm>

src/ReactAdapter.php

@@ -20,6 +20,7 @@ class ReactAdapter implements LoopInterface
 
     public static function get(): LoopInterface
     {
+        /** @psalm-suppress RedundantPropertyInitializationCheck */
         self::$instances ??= new \WeakMap();
 
         $driver = EventLoop::getDriver();
@@ -31,6 +32,7 @@ public function __construct(?Driver $driver = null)
     {
         $this->driver = $driver ?? EventLoop::getDriver();
 
+        /** @psalm-suppress RedundantPropertyInitializationCheck */
         self::$instances ??= new \WeakMap();
         self::$instances[$this->driver] = $this;
     }