fail with a meaningful error when a needed package is missing

Author: xabbuh

src/Symfony/Component/PropertyInfo/Extractor/PhpDocExtractor.php

@@ -60,7 +60,7 @@ class PhpDocExtractor implements PropertyDescriptionExtractorInterface, Property
     public function __construct(DocBlockFactoryInterface $docBlockFactory = null, array $mutatorPrefixes = null, array $accessorPrefixes = null, array $arrayMutatorPrefixes = null)
     {
         if (!class_exists(DocBlockFactory::class)) {
-            throw new \LogicException(sprintf('Unable to use the "%s" class as the "phpdocumentor/reflection-docblock" package is not installed.', __CLASS__));
+            throw new \LogicException(sprintf('Unable to use the "%s" class as the "phpdocumentor/reflection-docblock" package is not installed. Try running composer require "phpdocumentor/reflection-docblock".', __CLASS__));
         }
 
         $this->docBlockFactory = $docBlockFactory ?: DocBlockFactory::createInstance();

src/Symfony/Component/PropertyInfo/Extractor/PhpStanExtractor.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\PropertyInfo\Extractor;
 
+use phpDocumentor\Reflection\Types\ContextFactory;
 use PHPStan\PhpDocParser\Ast\PhpDoc\InvalidTagValueNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\ParamTagValueNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\PhpDocNode;
@@ -59,6 +60,10 @@ final class PhpStanExtractor implements PropertyTypeExtractorInterface, Construc
      */
     public function __construct(array $mutatorPrefixes = null, array $accessorPrefixes = null, array $arrayMutatorPrefixes = null)
     {
+        if (!class_exists(ContextFactory::class)) {
+            throw new \LogicException(sprintf('Unable to use the "%s" class as the "phpdocumentor/type-resolver" package is not installed. Try running composer require "phpdocumentor/type-resolver".', __CLASS__));
+        }
+
         $this->phpStanTypeHelper = new PhpStanTypeHelper();
         $this->mutatorPrefixes = $mutatorPrefixes ?? ReflectionExtractor::$defaultMutatorPrefixes;
         $this->accessorPrefixes = $accessorPrefixes ?? ReflectionExtractor::$defaultAccessorPrefixes;