From 92f438b1465245e8da633bb7140f5b2cb212e809 Mon Sep 17 00:00:00 2001
From: IanDelMar <42134098+IanDelMar@users.noreply.github.com>
Date: Fri, 24 Feb 2023 10:22:27 +0100
Subject: [PATCH] remove deprecated instanceof ConstantStringType

See https://phpstan.org/blog/why-is-instanceof-type-wrong-and-getting-deprecated
---
 src/phpstan/GetThemeModReturnType.php | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/phpstan/GetThemeModReturnType.php b/src/phpstan/GetThemeModReturnType.php
index 1278d1aa..886436aa 100644
--- a/src/phpstan/GetThemeModReturnType.php
+++ b/src/phpstan/GetThemeModReturnType.php
@@ -54,14 +54,20 @@ class GetThemeModReturnType implements DynamicFunctionReturnTypeExtension {
 			$functionReflection->getVariants()
 		)->getReturnType();
 
-		if (!$argType instanceof ConstantStringType) {
-			return $defaultType;
+		if (count($argType->getConstantStrings()) === 0) {
+			return null;
 		}
 
-		// Return the default value if it is not an Understrap specific theme mod.
-		if (!in_array($argType->getValue(), self::$themeMods, true)) {
-			return $defaultType;
+		$returnType = [];
+		foreach ($argType->getConstantStrings() as $constantString) {
+			if (in_array($constantString->getValue(), self::$themeMods, true)) {
+				$returnType[] = new StringType();
+			} else {
+				$returnType[] = $defaultType;
+			}
 		}
+		$returnType = TypeCombinator::union(...$returnType);
+
 
 		// Without second argument the default value is false, but can be filtered.
 		$defaultType = new MixedType();
@@ -69,6 +75,6 @@ class GetThemeModReturnType implements DynamicFunctionReturnTypeExtension {
 			$defaultType = $scope->getType($functionCall->getArgs()[1]->value);
 		}
 
-		return TypeCombinator::union(new StringType(), $defaultType);
+		return TypeCombinator::union($returnType, $defaultType);
 	}
 }