Try

Author: VincentLanglet

src/Rules/Arrays/NonexistentOffsetInArrayDimFetchCheck.php

@@ -12,7 +12,9 @@
 use PHPStan\Rules\RuleLevelHelper;
 use PHPStan\Type\BenevolentUnionType;
 use PHPStan\Type\ErrorType;
+use PHPStan\Type\MixedType;
 use PHPStan\Type\Type;
+use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\TypeUtils;
 use PHPStan\Type\VerbosityLevel;
 use function count;
@@ -44,11 +46,18 @@ public function check(
 		Type $dimType,
 	): array
 	{
+		if (!$dimType instanceof MixedType) {
+			// Non allowed array keys will already be reported by InvalidKeyInArrayItemRule
+			$dimTypeToCheck = TypeCombinator::intersect($dimType, AllowedArrayKeysTypes::getType());
+		} else {
+			$dimTypeToCheck = $dimType;
+		}
+
 		$typeResult = $this->ruleLevelHelper->findTypeToCheck(
 			$scope,
 			NullsafeOperatorHelper::getNullsafeShortcircuitedExprRespectingScope($scope, $var),
 			$unknownClassPattern,
-			static fn (Type $type): bool => $type->hasOffsetValueType($dimType)->yes(),
+			static fn (Type $type): bool => $type->hasOffsetValueType($dimTypeToCheck)->yes(),
 		);
 		$type = $typeResult->getType();
 		if ($type instanceof ErrorType) {
@@ -61,7 +70,7 @@ public function check(
 
 		if ($type->hasOffsetValueType($dimType)->no()) {
 			return [
-				RuleErrorBuilder::message(sprintf('Offset %s does not exist on %s.', $dimType->describe(count($dimType->getConstantStrings()) > 0 ? VerbosityLevel::precise() : VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))
+				RuleErrorBuilder::message(sprintf('Offset %s does not exist on %s.', $dimTypeToCheck->describe(count($dimTypeToCheck->getConstantStrings()) > 0 ? VerbosityLevel::precise() : VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))
 					->identifier('offsetAccess.notFound')
 					->build(),
 			];
@@ -76,7 +85,6 @@ public function check(
 				$flattenedTypes = TypeUtils::flattenTypes($type);
 			}
 
-			$allowedArrayKeysTypes = AllowedArrayKeysTypes::getType();
 			foreach ($flattenedTypes as $innerType) {
 				if (
 					$this->reportPossiblyNonexistentGeneralArrayOffset
@@ -95,6 +103,7 @@ public function check(
 					$report = true;
 					break;
 				}
+
 				if ($dimType instanceof BenevolentUnionType) {
 					$flattenedInnerTypes = [$dimType];
 				} else {
@@ -112,7 +121,7 @@ public function check(
 
 			if ($report) {
 				return [
-					RuleErrorBuilder::message(sprintf('Offset %s might not exist on %s.', $dimType->describe(count($dimType->getConstantStrings()) > 0 ? VerbosityLevel::precise() : VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))
+					RuleErrorBuilder::message(sprintf('Offset %s might not exist on %s.', $dimTypeToCheck->describe(count($dimTypeToCheck->getConstantStrings()) > 0 ? VerbosityLevel::precise() : VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))
 						->identifier('offsetAccess.notFound')
 						->build(),
 				];