sfp-psalm-typed-local-variable-plugin

Installation

$ composer require --dev struggle-for-php/sfp-psalm-typed-local-variable-plugin
$ vendor/bin/psalm-plugin enable struggle-for-php/sfp-psalm-typed-local-variable-plugin

Demo

<?php
class Entity{}
interface Repository
{
 public function findOneById(int $id): ?Entity;
}
interface Mock{}
/** @return \DateTimeInterface&Mock */
function date_mock() {
 return new class('now') extends \DateTime implements Mock{};
}
class Demo
{
 /** @var Repository */
 private $repository;
 function typed_by_phpdoc() : void
 {
 /** @var string|null $nullable_string */
 $nullable_string = null;
 $nullable_string = "a";
 $nullable_string = true; // ERROR
 }
 function typed_by_assignement() : void
 {
 $date = new \DateTimeImmutable('now');
 if (\rand() % 2 === 0) {
 $date = new \DateTime('tomorrow'); // ERROR
 }
 $bool = true; //direct typed without doc-block
 $bool = false; // ok (currently, this plugin treats true|false as bool)
 $bool = 1; // ERROR
 }
 function mismatch_by_return() : void
 {
 /** @var Entity $entity */
 $entity = $this->repository->findOneById(1); // ERROR
 }
 function works_with_intersection() : void
 {
 /** @var \DateTimeInterface&Mock $date */
 $date = new \DateTime('now'); // ERROR
 $date = date_mock(); // success
 }
}

$ ./vendor/bin/psalm -c demo.psalm.xml
Scanning files...
Analyzing files...
E
ERROR: InvalidScalarTypedLocalVariableIssue - demo/demo.php:23:28 - Type true should be a subtype of null|string
 $nullable_string = true; // ERROR
ERROR: InvalidTypedLocalVariableIssue - demo/demo.php:30:21 - Type DateTime should be a subtype of DateTimeImmutable
 $date = new \DateTime('tomorrow'); // ERROR
ERROR: InvalidScalarTypedLocalVariableIssue - demo/demo.php:35:17 - Type 1 should be a subtype of bool
 $bool = 1; // ERROR
ERROR: InvalidTypedLocalVariableIssue - demo/demo.php:41:19 - Type Entity|null should be a subtype of Entity
 $entity = $this->repository->findOneById(1); // ERROR
ERROR: InvalidTypedLocalVariableIssue - demo/demo.php:47:17 - Type DateTime should be a subtype of DateTimeInterface&Mock
 $date = new \DateTime('now'); // ERROR
------------------------------
5 errors found
------------------------------

Plugin Issues

function foo(array $a) : void {
 /** @var string[] $x */
 $x = $a;
}

class A {}
class B extends A {}
function takesA(A $a) : void {
 /** @var B $b */
 $b = $a;
}

<issueHandlers>
 <PluginIssue name="MixedTypeCoercionTypedLocalVariableIssue">
 <errorLevel type="suppress">
 <file name="src/Foo.php"/>
 </errorLevel>
 </PluginIssue>
</issueHandlers>

Disclaimer

Limitation

/** @var string $var1 */
/** @var bool $var2 */
$var1 = 'string'; // cannot determine type for $var1
// should fix like below
/** @var string $var1 */
$var1 = 'string';
/** @var bool $var2 */
$var2 = true;

Todo