Add phpstan

Author: adriansuter

.gitattributes

@@ -11,4 +11,5 @@
 /.gitignore         export-ignore
 /.travis.yml        export-ignore
 /phpcs.xml.dist     export-ignore
+/phpstan.neon.dist  export-ignore
 /phpunit.xml.dist   export-ignore

composer.json

@@ -38,15 +38,21 @@
     "nikic/php-parser": "^4.4"
   },
   "require-dev": {
+    "phpstan/phpstan": "^0.12.25",
     "phpunit/phpunit": "^7.5",
     "squizlabs/php_codesniffer": "^3.5"
   },
   "scripts": {
     "test": [
       "@phpunit",
-      "@phpcs"
+      "@phpcs",
+      "@phpstan"
     ],
     "phpunit": "phpunit",
-    "phpcs": "phpcs"
+    "phpcs": "phpcs",
+    "phpstan": "phpstan analyse src --memory-limit=-1"
+  },
+  "config": {
+    "sort-packages": true
   }
 }

phpstan.neon.dist

@@ -0,0 +1,6 @@
+parameters:
+    level: max
+    ignoreErrors:
+      - message: '/Parameter \#3 \$microseconds of function stream_set_timeout expects int, int\|null given./'
+        path: src/FileStreamWrapper.php
+        count: 1