Phpstan to max level

phpstan.neon

@@ -1,10 +1,10 @@
+includes:
+    - /composer/vendor/phpstan/phpstan-mockery/extension.neon
+    - /composer/vendor/phpstan/phpstan-webmozart-assert/extension.neon
+
 parameters:
     ignoreErrors:
         # false positive
-        - '#Call to an undefined method object::getDocComment\(\)#'
+        - '#Method phpDocumentor\Reflection\DocBlock\Tags\Method::filterArguments() should return array<array> but returns array<array|string>#'
+        - "~Parameter #1 $function of function call_user_func_array expects callable(): mixed, array(string, 'create') given.~"
         - '#Cannot call method render\(\) on phpDocumentor\\Reflection\\DocBlock\\Description\|string#'
-        - '#Calling method create\(\) on possibly null value of type phpDocumentor\\Reflection\\DocBlock\\DescriptionFactory\|null#'
-        - '#Calling method resolve\(\) on possibly null value of type phpDocumentor\\Reflection\\(TypeResolver|FqsenResolver)\|null#'
-
-        # nested parents
-        - '#Calling method render\(\) on possibly null value of type phpDocumentor\\Reflection\\DocBlock\\Description\|string\|null#'

src/DocBlock/DescriptionFactory.php

@@ -14,6 +14,7 @@ declare(strict_types=1);
 namespace phpDocumentor\Reflection\DocBlock;
 
 use phpDocumentor\Reflection\Types\Context as TypeContext;
+use Webmozart\Assert\Assert;
 use const PREG_SPLIT_DELIM_CAPTURE;
 use function count;
 use function explode;
@@ -62,9 +63,28 @@ class DescriptionFactory
      */
     public function create(string $contents, ?TypeContext $context = null) : Description
     {
-        [$text, $tags] = $this->parse($this->lex($contents), $context);
+        $tokens   = $this->lex($contents);
+        $count    = count($tokens);
+        $tagCount = 0;
+        $tags     = [];
 
-        return new Description($text, $tags);
+        for ($i = 1; $i < $count; $i += 2) {
+            $tag = $this->tagFactory->create($tokens[$i], $context);
+            if ($tag !== null) {
+                $tags[] = $tag;
+            }
+            $tokens[$i] = '%' . ++$tagCount . '$s';
+        }
+
+        //In order to allow "literal" inline tags, the otherwise invalid
+        //sequence "{@}" is changed to "@", and "{}" is changed to "}".
+        //"%" is escaped to "%%" because of vsprintf.
+        //See unit tests for examples.
+        for ($i = 0; $i < $count; $i += 2) {
+            $tokens[$i] = str_replace(['{@}', '{}', '%'], ['@', '}', '%%'], $tokens[$i]);
+        }
+
+        return new Description(implode('', $tokens), $tags);
     }
 
     /**
@@ -81,7 +101,7 @@ class DescriptionFactory
             return [$contents];
         }
 
-        return preg_split(
+        $parts =  preg_split(
             '/\{
                 # "{@}" is not a valid inline tag. This ensures that we do not treat it as one, but treat it literally.
                 (?!@\})
@@ -110,35 +130,8 @@ class DescriptionFactory
             0,
             PREG_SPLIT_DELIM_CAPTURE
         );
-    }
-
-    /**
-     * Parses the stream of tokens in to a new set of tokens containing Tags.
-     *
-     * @param string[] $tokens
-     *
-     * @return string[]|Tag[]
-     */
-    private function parse(array $tokens, ?TypeContext $context = null) : array
-    {
-        $count    = count($tokens);
-        $tagCount = 0;
-        $tags     = [];
-
-        for ($i = 1; $i < $count; $i += 2) {
-            $tags[]     = $this->tagFactory->create($tokens[$i], $context);
-            $tokens[$i] = '%' . ++$tagCount . '$s';
-        }
-
-        //In order to allow "literal" inline tags, the otherwise invalid
-        //sequence "{@}" is changed to "@", and "{}" is changed to "}".
-        //"%" is escaped to "%%" because of vsprintf.
-        //See unit tests for examples.
-        for ($i = 0; $i < $count; $i += 2) {
-            $tokens[$i] = str_replace(['{@}', '{}', '%'], ['@', '}', '%%'], $tokens[$i]);
-        }
-
-        return [implode('', $tokens), $tags];
+        Assert::isArray($parts);
+        return $parts;
     }
 
     /**

src/DocBlock/ExampleFinder.php

@@ -96,8 +96,10 @@ class ExampleFinder
      * 2. Checks the source folder for the given filename
      * 3. Checks the 'examples' folder in the current working directory for examples
      * 4. Checks the path relative to the current working directory for the given filename
+     *
+     * @return string[] all lines of the example file
      */
-    private function getExampleFileContents(string $filename) : ?string
+    private function getExampleFileContents(string $filename) : ?array
     {
         $normalizedPath = null;
 
@@ -119,7 +121,8 @@ class ExampleFinder
             }
         }
 
-        return $normalizedPath && is_readable($normalizedPath) ? file($normalizedPath) : null;
+        $lines = $normalizedPath && is_readable($normalizedPath) ? file($normalizedPath) : false;
+        return  $lines !== false ? $lines : null;
     }
 
     /**

src/DocBlock/StandardTagFactory.php

@@ -28,6 +28,23 @@ use function count;
 use function get_class;
 use function preg_match;
 use function strpos;
+use phpDocumentor\Reflection\DocBlock\Tags\Author;
+use phpDocumentor\Reflection\DocBlock\Tags\Covers;
+use phpDocumentor\Reflection\DocBlock\Tags\Deprecated;
+use phpDocumentor\Reflection\DocBlock\Tags\Link;
+use phpDocumentor\Reflection\DocBlock\Tags\Method;
+use phpDocumentor\Reflection\DocBlock\Tags\Param;
+use phpDocumentor\Reflection\DocBlock\Tags\PropertyRead;
+use phpDocumentor\Reflection\DocBlock\Tags\Property;
+use phpDocumentor\Reflection\DocBlock\Tags\PropertyWrite;
+use phpDocumentor\Reflection\DocBlock\Tags\Return_;
+use phpDocumentor\Reflection\DocBlock\Tags\See;
+use phpDocumentor\Reflection\DocBlock\Tags\Since;
+use phpDocumentor\Reflection\DocBlock\Tags\Source;
+use phpDocumentor\Reflection\DocBlock\Tags\Throws;
+use phpDocumentor\Reflection\DocBlock\Tags\Uses;
+use phpDocumentor\Reflection\DocBlock\Tags\Var_;
+use phpDocumentor\Reflection\DocBlock\Tags\Version;
 
 /**
  * Creates a Tag object given the contents of a tag.
@@ -56,25 +73,25 @@ final class StandardTagFactory implements TagFactory
      *      FQCN to a class that handles it as an array value.
      */
     private $tagHandlerMappings = [
-        'author' => '\phpDocumentor\Reflection\DocBlock\Tags\Author',
-        'covers' => '\phpDocumentor\Reflection\DocBlock\Tags\Covers',
-        'deprecated' => '\phpDocumentor\Reflection\DocBlock\Tags\Deprecated',
+        'author' => Author::class,
+        'covers' => Covers::class,
+        'deprecated' => Deprecated::class,
         // 'example'        => '\phpDocumentor\Reflection\DocBlock\Tags\Example',
-        'link' => '\phpDocumentor\Reflection\DocBlock\Tags\Link',
-        'method' => '\phpDocumentor\Reflection\DocBlock\Tags\Method',
-        'param' => '\phpDocumentor\Reflection\DocBlock\Tags\Param',
-        'property-read' => '\phpDocumentor\Reflection\DocBlock\Tags\PropertyRead',
-        'property' => '\phpDocumentor\Reflection\DocBlock\Tags\Property',
-        'property-write' => '\phpDocumentor\Reflection\DocBlock\Tags\PropertyWrite',
-        'return' => '\phpDocumentor\Reflection\DocBlock\Tags\Return_',
-        'see' => '\phpDocumentor\Reflection\DocBlock\Tags\See',
-        'since' => '\phpDocumentor\Reflection\DocBlock\Tags\Since',
-        'source' => '\phpDocumentor\Reflection\DocBlock\Tags\Source',
-        'throw' => '\phpDocumentor\Reflection\DocBlock\Tags\Throws',
-        'throws' => '\phpDocumentor\Reflection\DocBlock\Tags\Throws',
-        'uses' => '\phpDocumentor\Reflection\DocBlock\Tags\Uses',
-        'var' => '\phpDocumentor\Reflection\DocBlock\Tags\Var_',
-        'version' => '\phpDocumentor\Reflection\DocBlock\Tags\Version',
+        'link' => Link::class,
+        'method' => Method::class,
+        'param' => Param::class,
+        'property-read' => PropertyRead::class,
+        'property' => Property::class,
+        'property-write' => PropertyWrite::class,
+        'return' => Return_::class,
+        'see' => See::class,
+        'since' => Since::class,
+        'source' => Source::class,
+        'throw' => Throws::class,
+        'throws' => Throws::class,
+        'uses' => Uses::class,
+        'var' => Var_::class,
+        'version' => Version::class,
     ];
 
     /**
@@ -149,7 +166,7 @@ final class StandardTagFactory implements TagFactory
     /**
      * {@inheritDoc}
      */
-    public function addService($service, $alias = null) : void
+    public function addService(object $service, $alias = null) : void
     {
         $this->serviceLocator[$alias ?: get_class($service)] = $service;
     }
@@ -215,6 +232,8 @@ final class StandardTagFactory implements TagFactory
 
     /**
      * Determines the Fully Qualified Class Name of the Factory or Tag (containing a Factory Method `create`).
+     *
+     * @return
      */
     private function findHandlerClassName(string $tagName, TypeContext $context) : string
     {
@@ -245,7 +264,7 @@ final class StandardTagFactory implements TagFactory
     {
         $arguments = [];
         foreach ($parameters as $parameter) {
-            $typeHint = $parameter->getClass() ? $parameter->getClass()->getName() : null;
+            $typeHint = $parameter->getClass() !== null ? $parameter->getClass()->getName() : null;
             if (isset($locator[$typeHint])) {
                 $arguments[] = $locator[$typeHint];
                 continue;

src/DocBlock/Tags/Covers.php

@@ -51,8 +51,11 @@ final class Covers extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::notEmpty($body);
+        Assert::notNull($descriptionFactory);
+        Assert::notNull($resolver);
 
         $parts = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
 
         return new static(
             $resolver->resolve($parts[0], $context),

src/DocBlock/Tags/Deprecated.php

@@ -43,7 +43,7 @@ final class Deprecated extends BaseTag implements Factory\StaticMethod
         [^\s\:]+\:\s*\$[^\$]+\$
     )';
 
-    /** @var string The version vector. */
+    /** @var string|null The version vector. */
     private $version = '';
 
     public function __construct(?string $version = null, ?Description $description = null)
@@ -74,6 +74,7 @@ final class Deprecated extends BaseTag implements Factory\StaticMethod
             );
         }
 
+        Assert::notNull($descriptionFactory);
         return new static(
             $matches[1],
             $descriptionFactory->create($matches[2] ?? '', $context)

src/DocBlock/Tags/Generic.php

@@ -54,7 +54,7 @@ class Generic extends BaseTag implements Factory\StaticMethod
         Assert::stringNotEmpty($name);
         Assert::notNull($descriptionFactory);
 
-        $description = $descriptionFactory && $body !== '' ? $descriptionFactory->create($body, $context) : null;
+        $description = $body !== '' ? $descriptionFactory->create($body, $context) : null;
 
         return new static($name, $description);
     }

src/DocBlock/Tags/Link.php

@@ -50,6 +50,7 @@ final class Link extends BaseTag implements Factory\StaticMethod
         Assert::notNull($descriptionFactory);
 
         $parts       = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
         $description = isset($parts[1]) ? $descriptionFactory->create($parts[1], $context) : null;
 
         return new static($parts[0], $description);

src/DocBlock/Tags/Method.php

@@ -44,7 +44,7 @@ final class Method extends BaseTag implements Factory\StaticMethod
     /** @var string */
     private $methodName = '';
 
-    /** @var string[] */
+    /** @var string[][] */
     private $arguments = [];
 
     /** @var bool */
@@ -87,7 +87,8 @@ final class Method extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : ?self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         // 1. none or more whitespace
         // 2. optionally the keyword "static" followed by whitespace
@@ -184,7 +185,7 @@ final class Method extends BaseTag implements Factory\StaticMethod
     }
 
     /**
-     * @return string[]
+     * @return string[][]
      */
     public function getArguments() : array
     {
@@ -221,7 +222,7 @@ final class Method extends BaseTag implements Factory\StaticMethod
     }
 
     /**
-     * @param mixed[][] $arguments
+     * @param array<string|mixed[]> $arguments
      *
      * @return mixed[][]
      */

src/DocBlock/Tags/Param.php

@@ -66,32 +66,34 @@ final class Param extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        Assert::isArray($parts);
         $type         = null;
         $variableName = '';
         $isVariadic   = false;
 
         // if the first item that is encountered is not a variable; it is a type
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && ($parts[0][0] !== '$')) {
             $type = $typeResolver->resolve(array_shift($parts), $context);
             array_shift($parts);
         }
 
         // if the next item starts with a $ or ...$ it must be the variable name
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) &&
+        if (isset($parts[0]) && ($parts[0] !== '') &&
             (strpos($parts[0], '$') === 0 || strpos($parts[0], '...$') === 0)
         ) {
             $variableName = array_shift($parts);
             array_shift($parts);
 
-            if (substr($variableName, 0, 3) === '...') {
+            if ($variableName !== null && strpos($variableName, '...') === 0) {
                 $isVariadic   = true;
                 $variableName = substr($variableName, 3);
             }
 
-            if (substr($variableName, 0, 1) === '$') {
+            if ($variableName !== null && strpos($variableName, '$') === 0) {
                 $variableName = substr($variableName, 1);
             }
         }

src/DocBlock/Tags/Property.php

@@ -23,7 +23,7 @@ use const PREG_SPLIT_DELIM_CAPTURE;
 use function array_shift;
 use function implode;
 use function preg_split;
-use function strlen;
+use function strpos;
 use function substr;
 
 /**
@@ -57,24 +57,26 @@ class Property extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
-        $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        $parts = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        Assert::isArray($parts);
         $type         = null;
         $variableName = '';
 
         // if the first item that is encountered is not a variable; it is a type
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && ($parts[0][0] !== '$')) {
             $type = $typeResolver->resolve(array_shift($parts), $context);
             array_shift($parts);
         }
 
         // if the next item starts with a $ or ...$ it must be the variable name
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] === '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && (strpos($parts[0], '$') === 0)) {
             $variableName = array_shift($parts);
             array_shift($parts);
 
-            if (substr($variableName, 0, 1) === '$') {
+            if ($variableName !== null && strpos($variableName, '$') === 0) {
                 $variableName = substr($variableName, 1);
             }
         }

src/DocBlock/Tags/PropertyRead.php

@@ -57,24 +57,26 @@ class PropertyRead extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        Assert::isArray($parts);
         $type         = null;
         $variableName = '';
 
         // if the first item that is encountered is not a variable; it is a type
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && ($parts[0][0] !== '$')) {
             $type = $typeResolver->resolve(array_shift($parts), $context);
             array_shift($parts);
         }
 
         // if the next item starts with a $ or ...$ it must be the variable name
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] === '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && (strpos($parts[0], '$') === 0)) {
             $variableName = array_shift($parts);
             array_shift($parts);
 
-            if (substr($variableName, 0, 1) === '$') {
+            if ($variableName !== null && strpos($variableName, '$') === 0) {
                 $variableName = substr($variableName, 1);
             }
         }

src/DocBlock/Tags/PropertyWrite.php

@@ -24,6 +24,7 @@ use function array_shift;
 use function implode;
 use function preg_split;
 use function strlen;
+use function strpos;
 use function substr;
 
 /**
@@ -57,14 +58,16 @@ class PropertyWrite extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        Assert::isArray($parts);
         $type         = null;
         $variableName = '';
 
         // if the first item that is encountered is not a variable; it is a type
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && ($parts[0][0] !== '$')) {
             $type = $typeResolver->resolve(array_shift($parts), $context);
             array_shift($parts);
         }
@@ -74,7 +77,7 @@ class PropertyWrite extends BaseTag implements Factory\StaticMethod
             $variableName = array_shift($parts);
             array_shift($parts);
 
-            if (substr($variableName, 0, 1) === '$') {
+            if ($variableName !== null && strpos($variableName, '$') === 0) {
                 $variableName = substr($variableName, 1);
             }
         }

src/DocBlock/Tags/Return_.php

@@ -47,9 +47,11 @@ final class Return_ extends BaseTag implements Factory\StaticMethod
         ?DescriptionFactory $descriptionFactory = null,
         ?TypeContext $context = null
     ) : self {
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
 
         $type        = $typeResolver->resolve($parts[0] ?? '', $context);
         $description = $descriptionFactory->create($parts[1] ?? '', $context);

src/DocBlock/Tags/See.php

@@ -49,13 +49,15 @@ class See extends BaseTag implements Factory\StaticMethod
      */
     public static function create(
         string $body,
-        ?FqsenResolver $resolver = null,
+        ?FqsenResolver $typeResolver = null,
         ?DescriptionFactory $descriptionFactory = null,
         ?TypeContext $context = null
     ) : self {
-        Assert::allNotNull([$resolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts       = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
         $description = isset($parts[1]) ? $descriptionFactory->create($parts[1], $context) : null;
 
         // https://tools.ietf.org/html/rfc2396#section-3
@@ -63,7 +65,7 @@ class See extends BaseTag implements Factory\StaticMethod
             return new static(new Url($parts[0]), $description);
         }
 
-        return new static(new FqsenRef($resolver->resolve($parts[0], $context)), $description);
+        return new static(new FqsenRef($typeResolver->resolve($parts[0], $context)), $description);
     }
 
     /**

src/DocBlock/Tags/Since.php

@@ -43,7 +43,7 @@ final class Since extends BaseTag implements Factory\StaticMethod
         [^\s\:]+\:\s*\$[^\$]+\$
     )';
 
-    /** @var string The version vector. */
+    /** @var string|null The version vector. */
     private $version = '';
 
     public function __construct(?string $version = null, ?Description $description = null)
@@ -68,6 +68,7 @@ final class Since extends BaseTag implements Factory\StaticMethod
             return null;
         }
 
+        Assert::notNull($descriptionFactory);
         return new static(
             $matches[1],
             $descriptionFactory->create($matches[2] ?? '', $context)

src/DocBlock/Tags/Throws.php

@@ -47,9 +47,11 @@ final class Throws extends BaseTag implements Factory\StaticMethod
         ?DescriptionFactory $descriptionFactory = null,
         ?TypeContext $context = null
     ) : self {
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
 
         $type        = $typeResolver->resolve($parts[0] ?? '', $context);
         $description = $descriptionFactory->create($parts[1] ?? '', $context);

src/DocBlock/Tags/Uses.php

@@ -50,9 +50,12 @@ final class Uses extends BaseTag implements Factory\StaticMethod
         ?DescriptionFactory $descriptionFactory = null,
         ?TypeContext $context = null
     ) : self {
-        Assert::allNotNull([$resolver, $descriptionFactory]);
+        Assert::notNull($resolver);
+        Assert::notNull($descriptionFactory);
 
         $parts = preg_split('/\s+/Su', $body, 2);
+        Assert::isArray($parts);
+        Assert::allString($parts);
 
         return new static(
             $resolver->resolve($parts[0], $context),

src/DocBlock/Tags/Var_.php

@@ -57,24 +57,29 @@ class Var_ extends BaseTag implements Factory\StaticMethod
         ?TypeContext $context = null
     ) : self {
         Assert::stringNotEmpty($body);
-        Assert::allNotNull([$typeResolver, $descriptionFactory]);
+        Assert::notNull($typeResolver);
+        Assert::notNull($descriptionFactory);
 
         $parts        = preg_split('/(\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
+        Assert::isArray($parts);
+        Assert::allString($parts);
         $type         = null;
         $variableName = '';
 
         // if the first item that is encountered is not a variable; it is a type
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] !== '$')) {
-            $type = $typeResolver->resolve(array_shift($parts), $context);
+        if (isset($parts[0]) && ($parts[0] !== '') && ($parts[0][0] !== '$')) {
+            if ($typeResolver !== null) {
+                $type = $typeResolver->resolve(array_shift($parts), $context);
+            }
             array_shift($parts);
         }
 
         // if the next item starts with a $ or ...$ it must be the variable name
-        if (isset($parts[0]) && (strlen($parts[0]) > 0) && ($parts[0][0] === '$')) {
+        if (isset($parts[0]) && ($parts[0] !== '') && (strpos($parts[0], '$') === 0)) {
             $variableName = array_shift($parts);
             array_shift($parts);
 
-            if (substr($variableName, 0, 1) === '$') {
+            if ($variableName !== null && strpos($variableName, '$') === 0) {
                 $variableName = substr($variableName, 1);
             }
         }

src/DocBlock/Tags/Version.php

@@ -43,7 +43,7 @@ final class Version extends BaseTag implements Factory\StaticMethod
         [^\s\:]+\:\s*\$[^\$]+\$
     )';
 
-    /** @var string The version vector. */
+    /** @var string|null The version vector. */
     private $version = '';
 
     public function __construct(?string $version = null, ?Description $description = null)
@@ -68,9 +68,14 @@ final class Version extends BaseTag implements Factory\StaticMethod
             return null;
         }
 
+        $description = null;
+        if ($descriptionFactory !== null) {
+            $description = $descriptionFactory->create($matches[2] ?? '', $context);
+        }
+
         return new static(
             $matches[1],
-            $descriptionFactory->create($matches[2] ?? '', $context)
+            $description
         );
     }
 

src/DocBlockFactory.php

@@ -230,7 +230,7 @@ final class DocBlockFactory implements DocBlockFactoryInterface
      * @param string        $tags    Tag block to parse.
      * @param Types\Context $context Context of the parsed Tag
      *
-     * @return DocBlock\Tag[]|string[]|null[]
+     * @return DocBlock\Tag[]
      */
     private function parseTagBlock(string $tags, Types\Context $context) : array
     {
@@ -239,9 +239,13 @@ final class DocBlockFactory implements DocBlockFactoryInterface
             return [];
         }
 
-        $result = $this->splitTagBlockIntoTagLines($tags);
-        foreach ($result as $key => $tagLine) {
-            $result[$key] = $this->tagFactory->create(trim($tagLine), $context);
+        $result = [];
+        $lines = $this->splitTagBlockIntoTagLines($tags);
+        foreach ($lines as $key => $tagLine) {
+            $tag = $this->tagFactory->create(trim($tagLine), $context);
+            if ($tag instanceof Tag) {
+                $result[$key] = $tag;
+            }
         }
 
         return $result;