[CodeQuality] Skip SingularSwitchToIfRector on nested break or continue in case body (#8500)

Author: samsonasik

rules-tests/CodeQuality/Rector/Switch_/SingularSwitchToIfRector/Fixture/closure_with_break.php.inc

@@ -0,0 +1,41 @@
+<?php
+
+namespace Rector\Tests\CodeQuality\Rector\Switch_\SingularSwitchToIfRector\Fixture;
+
+final class ClosureWithBreak
+{
+    public function run($value, array $items)
+    {
+        switch ($value) {
+            case 100:
+                $callback = function () use ($items) {
+                    foreach ($items as $item) {
+                        break;
+                    }
+                };
+                break;
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodeQuality\Rector\Switch_\SingularSwitchToIfRector\Fixture;
+
+final class ClosureWithBreak
+{
+    public function run($value, array $items)
+    {
+        if ($value === 100) {
+            $callback = function () use ($items) {
+                foreach ($items as $item) {
+                    break;
+                }
+            };
+        }
+    }
+}
+
+?>

rules-tests/CodeQuality/Rector/Switch_/SingularSwitchToIfRector/Fixture/skip_nested_break.php.inc

@@ -0,0 +1,21 @@
+<?php
+
+namespace Rector\Tests\CodeQuality\Rector\Switch_\SingularSwitchToIfRector\Fixture;
+
+final class SkipNestedBreak
+{
+    public function run($a, $b, $else, $value)
+    {
+        switch ($a) {
+            case $b:
+                $something = $else;
+                if (! $something) {
+                    break;
+                }
+                $another = $value;
+                break;
+        }
+    }
+}
+
+?>

rules/CodeQuality/Rector/Switch_/SingularSwitchToIfRector.php

@@ -7,10 +7,14 @@
 use PhpParser\Node;
 use PhpParser\Node\Expr;
 use PhpParser\Node\Expr\BinaryOp\Identical;
+use PhpParser\Node\FunctionLike;
 use PhpParser\Node\Stmt;
 use PhpParser\Node\Stmt\Break_;
+use PhpParser\Node\Stmt\Class_;
+use PhpParser\Node\Stmt\Continue_;
 use PhpParser\Node\Stmt\If_;
 use PhpParser\Node\Stmt\Switch_;
+use PhpParser\NodeVisitor;
 use Rector\Rector\AbstractRector;
 use Rector\Renaming\NodeManipulator\SwitchManipulator;
 use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
@@ -85,6 +89,11 @@ public function refactor(Node $node): array|If_|null
 
         $onlyCase = $node->cases[0];
 
+        // nested break/continue would lose the switch to target and cause a fatal error
+        if ($this->hasNestedBreakOrContinue($onlyCase->stmts)) {
+            return null;
+        }
+
         // only default → basically unwrap
         if (! $onlyCase->cond instanceof Expr) {
             // remove default clause because it cause syntax error
@@ -96,4 +105,34 @@ public function refactor(Node $node): array|If_|null
 
         return $if;
     }
+
+    /**
+     * @param Stmt[] $stmts
+     */
+    private function hasNestedBreakOrContinue(array $stmts): bool
+    {
+        $hasNested = false;
+
+        foreach ($stmts as $stmt) {
+            // top level break is removed by SwitchManipulator
+            if ($stmt instanceof Break_) {
+                continue;
+            }
+
+            $this->traverseNodesWithCallable($stmt, static function (Node $subNode) use (&$hasNested): ?int {
+                if ($subNode instanceof Class_ || $subNode instanceof FunctionLike) {
+                    return NodeVisitor::DONT_TRAVERSE_CURRENT_AND_CHILDREN;
+                }
+
+                if ($subNode instanceof Break_ || $subNode instanceof Continue_) {
+                    $hasNested = true;
+                    return NodeVisitor::STOP_TRAVERSAL;
+                }
+
+                return null;
+            });
+        }
+
+        return $hasNested;
+    }
 }