Fix PHP 7.4 and 8.0 CI

Pass the shallow flag positionally: the downgrader cannot resolve the
callee through Container::getByType() and left the named argument in.

Move the string-key unpack case into its own test file gated at PHP 8.1,
where string keys in array unpacking exist - below that the keys are
renumbered and T resolves to 0|'foo'.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YDUM2MMMRcgYQ7rLyeeyQZ

Author: canvural

src/Analyser/NodeScopeResolver.php

@@ -2516,7 +2516,7 @@ private function getStructuralArgType(MutatingScope $scope, Expr $expr): ?Type
 	private function getStructuralItemType(MutatingScope $scope, Expr $expr): Type
 	{
 		if ($expr instanceof Expr\Closure || $expr instanceof Expr\ArrowFunction) {
-			return $this->container->getByType(ClosureTypeResolver::class)->getClosureType($scope, $expr, shallow: true);
+			return $this->container->getByType(ClosureTypeResolver::class)->getClosureType($scope, $expr, true);
 		}
 
 		if (!$this->argConsumesResolvedParameterType($expr)) {

tests/PHPStan/Analyser/nsrt/closure-passed-to-type-nested-unpack.php

@@ -0,0 +1,23 @@
+<?php // lint >= 8.1
+
+declare(strict_types = 1);
+
+namespace ClosurePassedToTypeNestedUnpack;
+
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template T
+ * @param array<T, \Closure(T): void> $callbacks
+ */
+function acceptKeyedGenericWithUnpack(array $callbacks): void {}
+
+/** @param array<'z', \Closure('z'): void> $more */
+function withUnpack(array $more): void {
+	acceptKeyedGenericWithUnpack([
+		...$more,
+		'foo' => function ($value): void {
+			assertType("'foo'|'z'", $value);
+		},
+	]);
+};

tests/PHPStan/Analyser/nsrt/closure-passed-to-type-nested.php

@@ -149,19 +149,3 @@ function acceptNestedGeneric(array $callbacks): void {}
 		assertType("'x'", $value);
 	}],
 ]);
-
-/**
- * @template T
- * @param array<T, \Closure(T): void> $callbacks
- */
-function acceptKeyedGenericWithUnpack(array $callbacks): void {}
-
-/** @param array<'z', \Closure('z'): void> $more */
-function withUnpack(array $more): void {
-	acceptKeyedGenericWithUnpack([
-		...$more,
-		'foo' => function ($value): void {
-			assertType("'foo'|'z'", $value);
-		},
-	]);
-};