check for return type hints with interfaces

analyse.php

<?php

require __DIR__.'/test.file.php';

$class = new ReflectionClass(Some\TheThing::class);

////
// Better way to find if the class has strict_type enabled
////
$tokens = token_get_all(file_get_contents(__DIR__.'/test.file.php'));

foreach ($tokens as $key => $token) {

	if (is_array($token)) {
		$foundKey = array_search('strict_types', $token);
		if (is_bool($foundKey) === false) {
			if ((bool) $tokens[$key+2][1] === false) {
				throw new \RuntimeException('File is not strict, no need');
			}
		}

	}

}
////
// End of strict_type check
////

foreach ($class->getMethods() as $method) {

	if (strpos($method->getDocComment(), '@inheritdoc') !== false) {

		foreach ($class->getInterfaces() as $interface) {

			if ($interface->hasMethod($method->getName())) {

				$intMeth = $interface->getMethod(
					$method->getName()
				);

				if (strpos($intMeth->getDocComment(), '@return')) {

					if (preg_match('/(string|array|float|int)/', $intMeth->getDocComment(), $match)) {

						if (
							$method->hasReturnType()
							&& (string) $method->getReturnType() === $match[0]
						) {
							continue;
						}


						$log[] = sprintf(
							"%s#%s should have a return type of [%s]\n(as per %s#%s)",
							$class->getName(),
							$method->getName(),
							$match[0],
							$interface->getName(),
							$intMeth->getName()
						);
					}

				}
			}

		}
	}

}

var_dump($log);

test.file.php

<?php
declare(strict_types=1);
namespace Some;
interface Something
{
	/** @return string */
	function getString();
	/** @return int */
	function getInt();
	/** @return float */
	function getFloat();
	/** @return null */
	function getNull();
}

final class TheThing implements Something
{
	/** @inheritdoc */
	function getString() :string { return 'string'; }
	/** @inheritdoc */
	function getInt() { return 1; }
	/** @inheritdoc */
	function getFloat() { return 3.14; }
	/** @inheritdoc */
	function getNull() { return null; }
}