Use argument types as parameter types for inline closures (#7798)

Author: leongersen

conf/config.neon

@@ -417,6 +417,16 @@ services:
 		tags:
 			- phpstan.parser.richParserNodeVisitor
 
+	-
+		class: PHPStan\Parser\ClosureArgVisitor
+		tags:
+			- phpstan.parser.richParserNodeVisitor
+
+	-
+		class: PHPStan\Parser\ArrowFunctionArgVisitor
+		tags:
+			- phpstan.parser.richParserNodeVisitor
+
 	-
 		class: PHPStan\Parser\NewAssignedToPropertyVisitor
 		tags:

src/Analyser/NodeScopeResolver.php

@@ -108,6 +108,7 @@
 use PHPStan\Reflection\InitializerExprTypeResolver;
 use PHPStan\Reflection\MethodReflection;
 use PHPStan\Reflection\Native\NativeMethodReflection;
+use PHPStan\Reflection\Native\NativeParameterReflection;
 use PHPStan\Reflection\ParametersAcceptor;
 use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Reflection\Php\PhpMethodReflection;
@@ -2960,21 +2961,42 @@ private function processClosureNode(
 
 		$byRefUses = [];
 
-		if ($passedToType !== null && !$passedToType->isCallable()->no()) {
+		$callableParameters = null;
+		$closureCallArgs = $expr->getAttribute('closureCallArgs');
+
+		if ($closureCallArgs !== null) {
+			$acceptors = $scope->getType($expr)->getCallableParametersAcceptors($scope);
+			if (count($acceptors) === 1) {
+				$callableParameters = $acceptors[0]->getParameters();
+
+				foreach ($callableParameters as $index => $callableParameter) {
+					if (!isset($closureCallArgs[$index])) {
+						continue;
+					}
+
+					$type = $scope->getType($closureCallArgs[$index]->value);
+					$callableParameters[$index] = new NativeParameterReflection(
+						$callableParameter->getName(),
+						$callableParameter->isOptional(),
+						$type,
+						$callableParameter->passedByReference(),
+						$callableParameter->isVariadic(),
+						$callableParameter->getDefaultValue(),
+					);
+				}
+			}
+		} elseif ($passedToType !== null && !$passedToType->isCallable()->no()) {
 			if ($passedToType instanceof UnionType) {
 				$passedToType = TypeCombinator::union(...array_filter(
 					$passedToType->getTypes(),
 					static fn (Type $type) => $type->isCallable()->yes(),
 				));
 			}
 
-			$callableParameters = null;
 			$acceptors = $passedToType->getCallableParametersAcceptors($scope);
 			if (count($acceptors) === 1) {
 				$callableParameters = $acceptors[0]->getParameters();
 			}
-		} else {
-			$callableParameters = null;
 		}
 
 		$useScope = $scope;
@@ -3101,21 +3123,42 @@ private function processArrowFunctionNode(
 			$nodeCallback($expr->returnType, $scope);
 		}
 
-		if ($passedToType !== null && !$passedToType->isCallable()->no()) {
+		$callableParameters = null;
+		$arrowFunctionCallArgs = $expr->getAttribute('arrowFunctionCallArgs');
+
+		if ($arrowFunctionCallArgs !== null) {
+			$acceptors = $scope->getType($expr)->getCallableParametersAcceptors($scope);
+			if (count($acceptors) === 1) {
+				$callableParameters = $acceptors[0]->getParameters();
+
+				foreach ($callableParameters as $index => $callableParameter) {
+					if (!isset($arrowFunctionCallArgs[$index])) {
+						continue;
+					}
+
+					$type = $scope->getType($arrowFunctionCallArgs[$index]->value);
+					$callableParameters[$index] = new NativeParameterReflection(
+						$callableParameter->getName(),
+						$callableParameter->isOptional(),
+						$type,
+						$callableParameter->passedByReference(),
+						$callableParameter->isVariadic(),
+						$callableParameter->getDefaultValue(),
+					);
+				}
+			}
+		} elseif ($passedToType !== null && !$passedToType->isCallable()->no()) {
 			if ($passedToType instanceof UnionType) {
 				$passedToType = TypeCombinator::union(...array_filter(
 					$passedToType->getTypes(),
 					static fn (Type $type) => $type->isCallable()->yes(),
 				));
 			}
 
-			$callableParameters = null;
 			$acceptors = $passedToType->getCallableParametersAcceptors($scope);
 			if (count($acceptors) === 1) {
 				$callableParameters = $acceptors[0]->getParameters();
 			}
-		} else {
-			$callableParameters = null;
 		}
 
 		$arrowFunctionScope = $scope->enterArrowFunction($expr, $callableParameters);

src/Parser/ArrowFunctionArgVisitor.php

@@ -0,0 +1,24 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Parser;
+
+use PhpParser\Node;
+use PhpParser\NodeVisitorAbstract;
+use function count;
+
+class ArrowFunctionArgVisitor extends NodeVisitorAbstract
+{
+
+	public function enterNode(Node $node): ?Node
+	{
+		if ($node instanceof Node\Expr\FuncCall && $node->name instanceof Node\Expr\ArrowFunction) {
+			$args = $node->getArgs();
+
+			if (count($args) > 0) {
+				$node->name->setAttribute('arrowFunctionCallArgs', $args);
+			}
+		}
+		return null;
+	}
+
+}

src/Parser/ClosureArgVisitor.php

@@ -0,0 +1,24 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Parser;
+
+use PhpParser\Node;
+use PhpParser\NodeVisitorAbstract;
+use function count;
+
+class ClosureArgVisitor extends NodeVisitorAbstract
+{
+
+	public function enterNode(Node $node): ?Node
+	{
+		if ($node instanceof Node\Expr\FuncCall && $node->name instanceof Node\Expr\Closure) {
+			$args = $node->getArgs();
+
+			if (count($args) > 0) {
+				$node->name->setAttribute('closureCallArgs', $args);
+			}
+		}
+		return null;
+	}
+
+}

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -971,6 +971,12 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Arrays/data/bug-7469.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Variables/data/bug-3391.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6901.php');
+
+		if (PHP_VERSION_ID >= 70400) {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/arrow-function-argument-type.php');
+		}
+
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/closure-argument-type.php');
 	}
 
 	/**

tests/PHPStan/Analyser/data/arrow-function-argument-type.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace ArrowFunctionArgumentType;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+	/**
+	 * @param array{a: int} $array
+	 */
+	public function doFoo(int $integer, array $array, ?string $nullableString)
+	{
+		(fn($context) => assertType('int', $context))($integer);
+
+		(fn($context) => assertType('array{a: int}', $context))($array);
+
+		(fn($context) => assertType('string|null', $context))($nullableString);
+
+		(fn($a, $b, $c) => assertType('array{int, array{a: int}, string|null}', [$a, $b, $c]))($integer, $array, $nullableString);
+
+		(fn($a, $b, $c = null) => assertType('array{int, array{a: int}, mixed}', [$a, $b, $c]))($integer, $array);
+	}
+
+}

tests/PHPStan/Analyser/data/closure-argument-type.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace ClosureArgumentType;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+	/**
+	 * @param array{a: int} $array
+	 */
+	public function doFoo(int $integer, array $array, ?string $nullableString)
+	{
+		(function($context) {
+			assertType('int', $context);
+		})($integer);
+
+		(function($context) {
+			assertType('array{a: int}', $context);
+		})($array);
+
+		(function($context) {
+			assertType('string|null', $context);
+		})($nullableString);
+
+		(function($context1, $context2, $context3) {
+			assertType('int', $context1);
+			assertType('array{a: int}', $context2);
+			assertType('string|null', $context3);
+		})($integer, $array, $nullableString);
+
+		(function($context1, $context2, $context3 = null) {
+			assertType('int', $context1);
+			assertType('array{a: int}', $context2);
+			assertType('mixed', $context3);
+		})($integer, $array);
+	}
+
+}