README

Resolve (fully-qualify) types from PHPStan's PHPDoc parser.

💾 Installation

This package can be installed with Composer, simply run the following:

composer require uuf6429/phpstan-phpdoc-type-resolver

Consider using --dev if you intend to use this library during development only.

🤔 Why?

Because phpstan/phpdoc-parser doesn't resolve types (it's not its responsibility) and phpdocument/type-resolver currently has some major limitations.

🚀 Usage

In principle the resolver needs two things:

1. The PHPStan-PHPDoc type (an instance of TypeNode).
2. 'Scope' information of where that type occurred.

There are two ways to retrieve that information, as shown below.

Important: The resolver will always convert some specific PHPStan types into something else as follows:

• *ThisTypeNode is converted into IdentifierTypeNode for the currently-passed class.
• *GenericTypeNode to either ConcreteGenericTypeNode or TemplateGenericTypeNode based on if the received instance contains unresolved generic/template types.
• PHPStan locally-defined or imported-types, a TypeDefTypeNode will be provided (instead of an IdentifierTypeNode with just the type name).

(*) conversion is mandatory, failures will trigger some sort of exception (meaning: the original type should never be returned).

😎 Via Reflection

Let's assume we have a \My\Project\Greeter class with a greet method, here's how we can resolve that method's return type:

<?php

// Reflect our class method
$reflector = new \ReflectionMethod(\My\Project\Greeter::class, 'greet');

// Use the provided factory to easily parse the PHPDoc, which additionally automatically resolves the types
$docBlock = \uuf6429\PHPStanPHPDocTypeResolver\PhpDoc\Factory::createInstance()
    ->createFromReflector($reflector);

// And finally, retrieve the resolved type of the return tag
/** @var \PHPStan\PhpDocParser\Ast\PhpDoc\ReturnTagValueNode $returnTag */
$returnTag = $docBlock->getTag('@return');
$finalReturnType = $returnTag->type;

🙈 Without Factory/DocBlock Wrapper

Assuming as before that we have a \My\Project\Greeter class with a greet method, here's the longer way to resolve the method's return type:

<?php

// Reflect our class method
$reflector = new \ReflectionMethod(\My\Project\Greeter::class, 'greet');

// Use the scope resolver to get information about that method
$scopeResolver = new \uuf6429\PHPStanPHPDocTypeResolver\PhpDoc\ReflectorScopeResolver();
$scope = $scopeResolver->resolve($reflector);

// Parse the PHPDoc block with PHPStan PHPDoc parser
$lexer = new \PHPStan\PhpDocParser\Lexer\Lexer();
$constExprParser = new \PHPStan\PhpDocParser\Parser\ConstExprParser();
$typeParser = new \PHPStan\PhpDocParser\Parser\TypeParser($constExprParser);
$parser = new \PHPStan\PhpDocParser\Parser\PhpDocParser($typeParser, $constExprParser);
$docBlock = $parser->parse(
    new \PHPStan\PhpDocParser\Parser\TokenIterator(
        $lexer->tokenize($scope->comment)   // 👈 note that the scope resolver also retrieves the PHPDoc block for us
    )
);

// Finally, we initialize the type resolver and resolve the first return type of the doc block
$typeResolver = new \uuf6429\PHPStanPHPDocTypeResolver\TypeResolver();
$finalReturnType = $typeResolver->resolve($scope, $docBlock->getReturnTagValues()[0]->type);

🤪 Via Source Strings

It's also possible to resolve the type without actually loading the PHP source code (which is a requirement for reflection). However, this will take more work - the main difference is that you will need to set up the scope yourself.

Let's assume we want to resolve a type in a PHP source code string:

<?php

$source = <<<'PHP'
<?php

namespace My\Project\Services;

use My\Project\PersonEntity as Person;

class Greeter {
    /**
     * @param Person|object{name: string} $person
     */
    public function greet($person): void {
        echo "Hello, {$person->name}!";
    }
}

PHP;

// Construct the scope manually - automating this will take some work
$scope = new \uuf6429\PHPStanPHPDocTypeResolver\PhpDoc\Scope(
    // In-memory file; you could also use php memory streams etc
    file: 'data:base64,' . base64_encode($source),
    // approximate line where the type has occurred - everything else below has to be specified manually
    line: 73,
    class: 'My\Project\Services\Greeter',
    comment: <<<'PHP'
        /**
         * @param Person|object{name: string} $person
         */
        PHP
);

// The factory can also be used with a custom scope
$docBlock = \uuf6429\PHPStanPHPDocTypeResolver\PhpDoc\Factory::createInstance()
    ->createFromScope($scope);

// And as before, retrieve the resolved type of the return tag
/** @var \PHPStan\PhpDocParser\Ast\PhpDoc\ReturnTagValueNode $returnTag */
$returnTag = $docBlock->getTag('@return');
$finalReturnType = $returnTag->type;