Fix PHPStan build

composer.json

@@ -48,7 +48,7 @@
         }
     },
     "scripts": {
-        "phpstan": "vendor/bin/phpstan analyse src test --level 7 -c phpstan.neon",
+        "phpstan": "vendor/bin/phpstan analyse",
         "cs-check": "vendor/bin/php-cs-fixer fix --verbose --diff --dry-run",
         "cs-fix": "vendor/bin/php-cs-fixer fix --verbose --diff"
     },

phpstan.neon

@@ -1,4 +1,8 @@
 parameters:
+    level: 7
+    paths:
+        - src/
+        - test/
     ignoreErrors:
          - '/Symfony\\Component\\Console\\Event\\ConsoleExceptionEvent/'
          - '/Call to an undefined method Symfony\\Component\\Console\\Event\\ConsoleEvent::getExitCode\(\)\./'

src/ErrorTypesParser.php

@@ -55,6 +55,10 @@ private function convertErrorConstants(string $expression): string
             return $errorConstant[0];
         }, $expression);
 
+        if (null === $output) {
+            throw new \InvalidArgumentException('Unable to parse error types string: ' . $expression);
+        }
+
         return $output;
     }
 

test/ErrorTypesParserTest.php

@@ -20,4 +20,12 @@ public function test_error_types_parser_throws_exception_for_unwanted_values()
         $this->expectException(\InvalidArgumentException::class);
         $ex->parse();
     }
+
+    public function test_error_types_parser_throws_exception_for_unparsable_values()
+    {
+        $ex = new ErrorTypesParser('something-wrong');
+
+        $this->expectException(\InvalidArgumentException::class);
+        $ex->parse();
+    }
 }