[DowngradePhp81] Fix algo not on list on DowngradeHashAlgorithmXxHashRector (#200)

* [DowngradePhp81] Fix algo not on list on DowngradeHashAlgorithmXxHashRector

* skip first class callable

* fix exists

* ad test

* [ci-review] Rector Rectify

* Fix phpstan

---------

Co-authored-by: GitHub Action <[email protected]>

Author: samsonasik

rules-tests/DowngradePhp81/Rector/FuncCall/DowngradeHashAlgorithmXxHash/Fixture/skip_hash_not_on_list.php.inc

@@ -0,0 +1,11 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp81\Rector\FuncCall\DowngradeHashAlgorithmXxHash\Fixture;
+
+class SkipHashNotOnList
+{
+    public function run($arg)
+    {
+        return hash($arg, 'some-data-to-hash');
+    }
+}

rules/DowngradePhp81/Rector/FuncCall/DowngradeHashAlgorithmXxHashRector.php

@@ -9,7 +9,6 @@
 use PhpParser\Node\Expr\ConstFetch;
 use PhpParser\Node\Expr\FuncCall;
 use PhpParser\Node\Scalar\String_;
-use Rector\Core\Exception\ShouldNotHappenException;
 use Rector\Core\NodeAnalyzer\ArgsAnalyzer;
 use Rector\Core\PhpParser\Node\Value\ValueResolver;
 use Rector\Core\Rector\AbstractRector;
@@ -88,31 +87,34 @@ public function refactor(Node $node): ?Node
         $this->argNamedKey = 0;
 
         $algorithm = $this->getHashAlgorithm($node->getArgs());
-
-        if (! array_key_exists($algorithm, self::HASH_ALGORITHMS_TO_DOWNGRADE)) {
+        if ($algorithm === null || ! array_key_exists($algorithm, self::HASH_ALGORITHMS_TO_DOWNGRADE)) {
             return null;
         }
 
-        $arg = $node->args[$this->argNamedKey];
-
-        if (! $arg instanceof Arg) {
-            throw new ShouldNotHappenException();
+        $args = $node->getArgs();
+        if (! isset($args[$this->argNamedKey])) {
+            return null;
         }
 
+        $arg = $args[$this->argNamedKey];
         $arg->value = new String_(self::REPLACEMENT_ALGORITHM);
 
         return $node;
     }
 
     private function shouldSkip(FuncCall $funcCall): bool
     {
+        if ($funcCall->isFirstClassCallable()) {
+            return true;
+        }
+
         return ! $this->nodeNameResolver->isName($funcCall, 'hash');
     }
 
     /**
      * @param Arg[] $args
      */
-    private function getHashAlgorithm(array $args): string
+    private function getHashAlgorithm(array $args): ?string
     {
         $arg = null;
 
@@ -137,7 +139,7 @@ private function getHashAlgorithm(array $args): string
             $algorithmNode instanceof ConstFetch => $this->mapConstantToString(
                 $this->valueResolver->getValue($algorithmNode)
             ),
-            default => throw new ShouldNotHappenException(),
+            default => null,
         };
     }