From 0ac5412aa05c9bac128abf2c1dab6d453e1f9ce1 Mon Sep 17 00:00:00 2001
From: Abdul Malik Ikhsan <samsonasik@gmail.com>
Date: Sun, 25 Apr 2021 14:07:36 +0700
Subject: [PATCH] [Php80] Add default case when variable initialized on
 ChangeSwitchToMatchRector (#6230)

* Add failing test fixture for ChangeSwitchToMatchRector

# Failing Test for ChangeSwitchToMatchRector

Based on https://getrector.org/demo/f7f2ba48-3c19-4fdb-bc0a-e956e037eefd

It's important to add the default case to prevent this error when passing another code:
```
Fatal error: Uncaught UnhandledMatchError: Unhandled match value of type int
```

https://3v4l.org/E64Um

* Closes #6216

* phpstan

* phpstan

Co-authored-by: Ruud Kamphuis <ruudk@users.noreply.github.com>
---
 ..._case_when_variable_is_initialized.php.inc | 40 +++++++++++++++++++
 .../Switch_/ChangeSwitchToMatchRector.php     | 27 ++++++++++++-
 2 files changed, 66 insertions(+), 1 deletion(-)
 create mode 100644 rules-tests/Php80/Rector/Switch_/ChangeSwitchToMatchRector/Fixture/add_default_case_when_variable_is_initialized.php.inc

diff --git a/rules-tests/Php80/Rector/Switch_/ChangeSwitchToMatchRector/Fixture/add_default_case_when_variable_is_initialized.php.inc b/rules-tests/Php80/Rector/Switch_/ChangeSwitchToMatchRector/Fixture/add_default_case_when_variable_is_initialized.php.inc
new file mode 100644
index 00000000000..76c93df0346
--- /dev/null
+++ b/rules-tests/Php80/Rector/Switch_/ChangeSwitchToMatchRector/Fixture/add_default_case_when_variable_is_initialized.php.inc
@@ -0,0 +1,40 @@
+<?php
+
+namespace Rector\Php80\Tests\Rector\Switch_\ChangeSwitchToMatchRector\Fixture;
+
+final class AddDefaultCaseWhenVariableIsInitialized
+{
+    public function getError(int $code) : ?string
+    {
+        $error = null;
+
+        switch ($code) {
+            case 10:
+                $error = 'code_10';
+                break;
+            case 11:
+                $error = 'code_11';
+                break;
+        }
+        return $error;
+    }
+}
+?>
+-----
+<?php
+
+namespace Rector\Php80\Tests\Rector\Switch_\ChangeSwitchToMatchRector\Fixture;
+
+final class AddDefaultCaseWhenVariableIsInitialized
+{
+    public function getError(int $code) : ?string
+    {
+        $error = match ($code) {
+            10 => 'code_10',
+            11 => 'code_11',
+            default => null,
+        };
+        return $error;
+    }
+}
+?>
diff --git a/rules/Php80/Rector/Switch_/ChangeSwitchToMatchRector.php b/rules/Php80/Rector/Switch_/ChangeSwitchToMatchRector.php
index 4ca19472b8f..1603ba0caf5 100644
--- a/rules/Php80/Rector/Switch_/ChangeSwitchToMatchRector.php
+++ b/rules/Php80/Rector/Switch_/ChangeSwitchToMatchRector.php
@@ -9,10 +9,12 @@ use PhpParser\Node\Expr;
 use PhpParser\Node\Expr\Assign;
 use PhpParser\Node\Expr\Match_;
 use PhpParser\Node\MatchArm;
+use PhpParser\Node\Name;
 use PhpParser\Node\Stmt\Expression;
 use PhpParser\Node\Stmt\Return_;
 use PhpParser\Node\Stmt\Switch_;
 use Rector\Core\Rector\AbstractRector;
+use Rector\NodeTypeResolver\Node\AttributeKey;
 use Rector\Php80\NodeAnalyzer\SwitchAnalyzer;
 use Rector\Php80\NodeResolver\SwitchExprsResolver;
 use Rector\Php80\ValueObject\CondAndExpr;
@@ -135,12 +137,35 @@ CODE_SAMPLE
         }
 
         if ($this->assignExpr) {
-            return new Assign($this->assignExpr, $match);
+            /** @var Expr $assignExpr */
+            $assignExpr = $this->assignExpr;
+            return $this->changeToAssign($node, $match, $assignExpr);
         }
 
         return $match;
     }
 
+    private function changeToAssign(Switch_ $switch, Match_ $match, Expr $assignExpr): Assign
+    {
+        $prevInitializedAssign = $this->betterNodeFinder->findFirstPreviousOfNode($switch, function (Node $node) use ($assignExpr): bool {
+            return $node instanceof Assign && $this->nodeComparator->areNodesEqual($node->var, $assignExpr);
+        });
+
+        $assign = new Assign($assignExpr, $match);
+        if ($prevInitializedAssign instanceof Assign) {
+            /** @var Match_ $expr */
+            $expr = $assign->expr;
+            $expr->arms[] = new MatchArm(null, $prevInitializedAssign->expr);
+
+            $parentAssign = $prevInitializedAssign->getAttribute(AttributeKey::PARENT_NODE);
+            if ($parentAssign instanceof Expression) {
+                $this->removeNode($parentAssign);
+            }
+        }
+
+        return $assign;
+    }
+
     private function shouldSkipSwitch(Switch_ $switch): bool
     {
         if (! $this->switchAnalyzer->hasEachCaseBreak($switch)) {