Add support for the key-of<...> and value-of<...> types

* Add support for the `key-of<...>` type

* Add support for the `value-of` type and add bsaic tests

* Add more tests

Author: ste93cry

src/PhpDoc/TypeNodeResolver.php

@@ -505,6 +505,18 @@ private function resolveGenericTypeNode(GenericTypeNode $typeNode, NameScope $na
 
 				return IntegerRangeType::fromInterval($min, $max);
 			}
+		} elseif ($mainTypeName === 'key-of') {
+			if (count($genericTypes) === 1) { // key-of<ValueType>
+				return $genericTypes[0]->getIterableKeyType();
+			}
+
+			return new ErrorType();
+		} elseif ($mainTypeName === 'value-of') {
+			if (count($genericTypes) === 1) { // value-of<ValueType>
+				return $genericTypes[0]->getIterableValueType();
+			}
+
+			return new ErrorType();
 		}
 
 		$mainType = $this->resolveIdentifierTypeNode($typeNode->type, $nameScope);

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -55,6 +55,8 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/native-types.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/type-change-after-array-access-assignment.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/iterator_to_array.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/key-of.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/value-of.php');
 
 		if (self::$useStaticReflectionProvider || extension_loaded('ds')) {
 			yield from $this->gatherAssertTypes(__DIR__ . '/data/ext-ds.php');

tests/PHPStan/Analyser/data/key-of.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace KeyOfType;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+	public const JFK = 'jfk';
+	public const LGA = 'lga';
+
+	private const ALL = [
+		self::JFK => 'John F. Kennedy Airport',
+		self::LGA => 'La Guardia Airport',
+	];
+
+	/**
+	 * @param key-of<self::ALL> $code
+	 */
+	public static function foo(string $code): void
+	{
+		assertType('\'jfk\'|\'lga\'', $code);
+	}
+
+	/**
+	 * @param key-of<'jfk'> $code
+	 */
+	public static function bar(string $code): void
+	{
+		assertType('string', $code);
+	}
+
+	/**
+	 * @param key-of<'jfk'|'lga'> $code
+	 */
+	public static function baz(string $code): void
+	{
+		assertType('string', $code);
+	}
+}

tests/PHPStan/Analyser/data/value-of.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace ValueOfType;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+	private const ALL = [
+		'jfk',
+		'lga',
+	];
+
+	/**
+	 * @param value-of<self::ALL> $code
+	 */
+	public static function foo(string $code): void
+	{
+		assertType('\'jfk\'|\'lga\'', $code);
+	}
+
+	/**
+	 * @param value-of<'jfk'> $code
+	 */
+	public static function bar(string $code): void
+	{
+		assertType('string', $code);
+	}
+
+	/**
+	 * @param value-of<'jfk'|'lga'> $code
+	 */
+	public static function baz(string $code): void
+	{
+		assertType('string', $code);
+	}
+}

tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php

@@ -500,6 +500,14 @@ public function testCallMethods(): void
 				1751,
 				'See: https://phpstan.org/blog/solving-phpstan-error-unable-to-resolve-template-type',
 			],
+			[
+				'Parameter #1 $code of method Test\\KeyOfParam::foo() expects \'jfk\'|\'lga\', \'sfo\' given.',
+				1777,
+			],
+			[
+				'Parameter #1 $code of method Test\\ValueOfParam::foo() expects \'John F. Kennedy…\'|\'La Guardia Airport\', \'Newark Liberty…\' given.',
+				1802,
+			],
 		]);
 	}
 
@@ -787,6 +795,14 @@ public function testCallMethodsOnThisOnly(): void
 				1751,
 				'See: https://phpstan.org/blog/solving-phpstan-error-unable-to-resolve-template-type',
 			],
+			[
+				'Parameter #1 $code of method Test\\KeyOfParam::foo() expects \'jfk\'|\'lga\', \'sfo\' given.',
+				1777,
+			],
+			[
+				'Parameter #1 $code of method Test\\ValueOfParam::foo() expects \'John F. Kennedy…\'|\'La Guardia Airport\', \'Newark Liberty…\' given.',
+				1802,
+			],
 		]);
 	}
 

tests/PHPStan/Rules/Methods/data/call-methods.php

@@ -1752,3 +1752,53 @@ public function doBar()
 	}
 
 }
+
+class KeyOfParam
+{
+	public const JFK = 'jfk';
+	public const LGA = 'lga';
+
+	private const ALL = [
+		self::JFK => 'John F. Kennedy Airport',
+		self::LGA => 'La Guardia Airport',
+	];
+
+	/**
+	 * @param key-of<self::ALL> $code
+	 */
+	public function foo(string $code): void
+	{
+	}
+
+	public function test(): void
+	{
+		$this->foo(KeyOfParam::JFK);
+		$this->foo('jfk');
+		$this->foo('sfo');
+	}
+}
+
+class ValueOfParam
+{
+	public const JFK = 'jfk';
+	public const LGA = 'lga';
+
+	public const ALL = [
+		self::JFK => 'John F. Kennedy Airport',
+		self::LGA => 'La Guardia Airport',
+	];
+
+	/**
+	 * @param value-of<self::ALL> $code
+	 */
+	public function foo(string $code): void
+	{
+	}
+
+	public function test(): void
+	{
+		$this->foo(ValueOfParam::ALL[ValueOfParam::JFK]);
+		$this->foo('John F. Kennedy Airport');
+		$this->foo('Newark Liberty International');
+	}
+}