resolves feedback

Addresses phpstan#3613 (comment)

Author: pmjones

src/Reflection/InitializerExprTypeResolver.php

@@ -482,7 +482,13 @@ public function resolveConcatType(Type $left, Type $right): Type
 			$accessoryTypes[] = new AccessoryLiteralStringType();
 		}
 
-		$this->appendAccessoryCasedStringTypes($leftStringType, $rightStringType, $accessoryTypes);
+		if ($leftStringType->isLowercaseString()->and($rightStringType->isLowercaseString())->yes()) {
+			$accessoryTypes[] = new AccessoryLowercaseStringType();
+		}
+
+		if ($leftStringType->isUppercaseString()->and($rightStringType->isUppercaseString())->yes()) {
+			$accessoryTypes[] = new AccessoryUppercaseStringType();
+		}
 
 		$leftNumericStringNonEmpty = TypeCombinator::remove($leftStringType, new ConstantStringType(''));
 		if ($leftNumericStringNonEmpty->isNumericString()->yes()) {
@@ -518,26 +524,6 @@ public function resolveConcatType(Type $left, Type $right): Type
 		return new StringType();
 	}
 
-	protected function appendAccessoryCasedStringTypes($leftStringType, $rightStringType, array &$accessoryTypes): void
-	{
-		$lower = $leftStringType->isLowercaseString()->and($rightStringType->isLowercaseString())->yes();
-		$upper = $leftStringType->isUppercaseString()->and($rightStringType->isUppercaseString())->yes();
-
-		if ($lower && $upper) {
-			return;
-		}
-
-		if ($lower) {
-			$accessoryTypes[] = new AccessoryLowercaseStringType();
-			return;
-		}
-
-		if ($upper) {
-			$accessoryTypes[] = new AccessoryUppercaseStringType();
-			return;
-		}
-	}
-
 	/**
 	 * @param callable(Expr): Type $getTypeCallback
 	 */

tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php

@@ -636,7 +636,7 @@ public function testArrayUdiffCallback(): void
 				6,
 			],
 			[
-				'Parameter #3 $data_comp_func of function array_udiff expects callable(1|2|3|4|5|6, 1|2|3|4|5|6): int, Closure(int, int): (literal-string&non-falsy-string&numeric-string) given.',
+				'Parameter #3 $data_comp_func of function array_udiff expects callable(1|2|3|4|5|6, 1|2|3|4|5|6): int, Closure(int, int): (literal-string&lowercase-string&non-falsy-string&numeric-string&uppercase-string) given.',
 				14,
 			],
 			[