Correctly infer template type from various callables

Author: ondrejmirtes

src/Type/CallableType.php

@@ -18,6 +18,7 @@
 use PHPStan\Reflection\Native\NativeParameterReflection;
 use PHPStan\Reflection\ParameterReflection;
 use PHPStan\Reflection\ParametersAcceptor;
+use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Reflection\PassedByReference;
 use PHPStan\Reflection\Php\DummyParameter;
 use PHPStan\ShouldNotHappenException;
@@ -405,10 +406,12 @@ public function inferTemplateTypes(Type $receivedType): TemplateTypeMap
 
 	private function inferTemplateTypesOnParametersAcceptor(ParametersAcceptor $parametersAcceptor): TemplateTypeMap
 	{
-		$typeMap = TemplateTypeMap::createEmpty();
+		$parameterTypes = array_map(static fn ($parameter) => $parameter->getType(), $this->getParameters());
+		$parametersAcceptor = ParametersAcceptorSelector::selectFromTypes($parameterTypes, [$parametersAcceptor], false);
 		$args = $parametersAcceptor->getParameters();
 		$returnType = $parametersAcceptor->getReturnType();
 
+		$typeMap = TemplateTypeMap::createEmpty();
 		foreach ($this->getParameters() as $i => $param) {
 			$paramType = $param->getType();
 			if (isset($args[$i])) {

src/Type/ClosureType.php

@@ -23,6 +23,7 @@
 use PHPStan\Reflection\Native\NativeParameterReflection;
 use PHPStan\Reflection\ParameterReflection;
 use PHPStan\Reflection\ParametersAcceptor;
+use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Reflection\PassedByReference;
 use PHPStan\Reflection\Php\ClosureCallUnresolvedMethodPrototypeReflection;
 use PHPStan\Reflection\Php\DummyParameter;
@@ -524,10 +525,12 @@ public function inferTemplateTypes(Type $receivedType): TemplateTypeMap
 
 	private function inferTemplateTypesOnParametersAcceptor(ParametersAcceptor $parametersAcceptor): TemplateTypeMap
 	{
-		$typeMap = TemplateTypeMap::createEmpty();
+		$parameterTypes = array_map(static fn ($parameter) => $parameter->getType(), $this->getParameters());
+		$parametersAcceptor = ParametersAcceptorSelector::selectFromTypes($parameterTypes, [$parametersAcceptor], false);
 		$args = $parametersAcceptor->getParameters();
 		$returnType = $parametersAcceptor->getReturnType();
 
+		$typeMap = TemplateTypeMap::createEmpty();
 		foreach ($this->getParameters() as $i => $param) {
 			$paramType = $param->getType();
 			if (isset($args[$i])) {

tests/PHPStan/Analyser/nsrt/bug-12691.php

@@ -0,0 +1,74 @@
+<?php declare(strict_types = 1);
+
+namespace Bug12691;
+
+use Closure;
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template T
+ */
+class Option
+{
+	/**
+	 * @param T $value
+	 */
+	public function __construct(
+		public mixed $value,
+	) {
+	}
+
+	/**
+	 * @template S
+	 * @param callable(T): S $callable
+	 * @return self<S>
+	 */
+	public function map($callable): self
+	{
+		return new self($callable($this->value));
+	}
+
+	/**
+	 * @template S
+	 * @param Closure(T): S $callable
+	 * @return self<S>
+	 */
+	public function mapClosure($callable): self
+	{
+		return new self($callable($this->value));
+	}
+}
+
+/**
+ * @param Option<non-empty-array<int>> $ints
+ */
+function doFoo(Option $ints): void {
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->map(array_values(...)));
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->map('array_values'));
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->map(static fn ($value) => array_values($value)));
+};
+
+/**
+ * @param Option<non-empty-array<int>> $ints
+ */
+function doFooClosure(Option $ints): void {
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->mapClosure(array_values(...)));
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->mapClosure(static fn ($value) => array_values($value)));
+};
+
+/**
+ * @template T
+ * @param array<T> $a
+ * @return ($a is non-empty-array ? non-empty-list<T> : list<T>)
+ */
+function myArrayValues(array $a): array {
+
+}
+
+/**
+ * @param Option<non-empty-array<int>> $ints
+ */
+function doBar(Option $ints): void {
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->mapClosure(myArrayValues(...)));
+	assertType('Bug12691\\Option<non-empty-list<int>>', $ints->mapClosure(static fn ($value) => myArrayValues($value)));
+};