Fix calling implode() with array<string> on level 9

src/PhpDoc/TypeNodeResolver.php

@@ -429,7 +429,7 @@ private function resolveIntersectionTypeNode(IntersectionTypeNode $typeNode, Nam
 	private function resolveArrayTypeNode(ArrayTypeNode $typeNode, NameScope $nameScope): Type
 	{
 		$itemType = $this->resolve($typeNode->type, $nameScope);
-		return new ArrayType(new MixedType(), $itemType);
+		return new ArrayType(new BenevolentUnionType([new IntegerType(), new StringType()]), $itemType);
 	}
 
 	private function resolveGenericTypeNode(GenericTypeNode $typeNode, NameScope $nameScope): Type
@@ -439,7 +439,7 @@ private function resolveGenericTypeNode(GenericTypeNode $typeNode, NameScope $na
 
 		if ($mainTypeName === 'array' || $mainTypeName === 'non-empty-array') {
 			if (count($genericTypes) === 1) { // array<ValueType>
-				$arrayType = new ArrayType(new MixedType(true), $genericTypes[0]);
+				$arrayType = new ArrayType(new BenevolentUnionType([new IntegerType(), new StringType()]), $genericTypes[0]);
 			} elseif (count($genericTypes) === 2) { // array<KeyType, ValueType>
 				$keyType = TypeCombinator::intersect($genericTypes[0], new UnionType([
 					new IntegerType(),

tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php

@@ -870,4 +870,10 @@ public function testBug2782(): void
 		]);
 	}
 
+	public function testBug5661(): void
+	{
+		$this->checkExplicitMixed = true;
+		$this->analyse([__DIR__ . '/data/bug-5661.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Functions/data/bug-5661.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Bug5661;
+
+class Foo
+{
+
+	/**
+	 * @param array<string> $array
+	 */
+	function sayHello(array $array): void
+	{
+		echo join(', ', $array) . PHP_EOL;
+	}
+
+	/**
+	 * @param string[] $array
+	 */
+	function sayHello2(array $array): void
+	{
+		echo join(', ', $array) . PHP_EOL;
+	}
+
+}