skip as array dim fetch dim

Author: samsonasik

rules-tests/DowngradePhp80/Rector/FuncCall/DowngradeSubstrFalsyRector/Fixture/skip_as_array_dim_fetch_dim.php.inc

@@ -0,0 +1,12 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp80\Rector\FuncCall\DowngradeSubstrFalsyRector\Fixture;
+
+class SkipAsArrayDimFetchDim
+{
+    public function run()
+    {
+        $data[substr('a', 2)] = 'foo';
+        var_dump($data);
+    }
+}

rules/DowngradePhp80/Rector/FuncCall/DowngradeSubstrFalsyRector.php

@@ -8,6 +8,7 @@
 use PhpParser\Node\Arg;
 use PhpParser\Node\ArrayItem;
 use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\ArrayDimFetch;
 use PhpParser\Node\Expr\AssignOp;
 use PhpParser\Node\Expr\BinaryOp\Concat;
 use PhpParser\Node\Expr\BinaryOp\Identical;
@@ -79,12 +80,13 @@ public function getNodeTypes(): array
             While_::class,
             Do_::class,
             ArrayItem::class,
+            ArrayDimFetch::class,
             FuncCall::class,
         ];
     }
 
     /**
-     * @param Cast|Empty_|BooleanNot|Ternary|Identical|Concat|MethodCall|StaticCall|AssignOp|If_|While_|Do_|ArrayItem|FuncCall $node
+     * @param Cast|Empty_|BooleanNot|Ternary|Identical|Concat|MethodCall|StaticCall|AssignOp|If_|While_|Do_|ArrayItem|ArrayDimFetch|FuncCall $node
      */
     public function refactor(Node $node): ?Node
     {
@@ -132,6 +134,14 @@ public function refactor(Node $node): ?Node
             return null;
         }
 
+        if ($node instanceof ArrayDimFetch) {
+            if ($node->dim instanceof Expr) {
+                $node->dim->setAttribute(self::IS_UNCASTABLE, true);
+            }
+
+            return null;
+        }
+
         if ($node instanceof CallLike) {
             if ($node->isFirstClassCallable()) {
                 return null;