Bail compact() enumeration for unsealed name arrays

`findConstantStrings` walked a constant array's explicit
`getValueTypes()` to collect the variable names, so an unsealed names
array — `compact(array{'foo', 'bar', ...<int, string>})` — produced a
sealed `array{foo: ..., bar: ...}`, ignoring that the unsealed extras
are further unknown variable names.

Return `null` (give up the precise shape) when the names array is
`isUnsealed()->yes()`, so the caller falls back to the general
`array<string, mixed>` signature.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: ondrejmirtes

src/Type/Php/CompactFunctionReturnTypeExtension.php

@@ -75,6 +75,13 @@ private function findConstantStrings(Type $type): ?array
 		}
 
 		if ($type instanceof ConstantArrayType) {
+			// Unsealed extras are unknown further variable names that can't
+			// be enumerated — bail so the caller falls back to the general
+			// `compact()` signature.
+			if ($type->isUnsealed()->yes()) {
+				return null;
+			}
+
 			$result = [];
 			foreach ($type->getValueTypes() as $valueType) {
 				$constantStrings = $this->findConstantStrings($valueType);

tests/PHPStan/Analyser/nsrt/compact.php

@@ -20,3 +20,15 @@ function (string $dolor): void {
 
 	assertType('array{}', compact([]));
 };
+
+/**
+ * @param array{'foo', 'bar', ...<int, string>} $names
+ */
+function unsealedNames(array $names): void {
+	$foo = 'x';
+	$bar = 'y';
+	// The unsealed `<int, string>` extras are unknown further variable
+	// names, so the result can't be enumerated as a sealed shape — it
+	// must widen to the general `compact()` signature.
+	assertType('array<string, mixed>', compact($names));
+};