[DeadCode] Add RemoveDuplicatedCaseInSwitchRector

config/set/dead-code/dead-code.yaml

@@ -23,3 +23,4 @@ services:
     Rector\DeadCode\Rector\Plus\RemoveZeroAndOneBinaryRector: ~
     Rector\DeadCode\Rector\ClassMethod\RemoveDelegatingParentCallRector: ~
     Rector\DeadCode\Rector\Instanceof_\RemoveDuplicatedInstanceOfRector: ~
+    Rector\DeadCode\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector: ~

packages/DeadCode/src/Rector/Switch_/RemoveDuplicatedCaseInSwitchRector.php

@@ -0,0 +1,89 @@
+<?php declare(strict_types=1);
+
+namespace Rector\DeadCode\Rector\Switch_;
+
+use PhpParser\Node;
+use PhpParser\Node\Stmt\Switch_;
+use Rector\Rector\AbstractRector;
+use Rector\RectorDefinition\CodeSample;
+use Rector\RectorDefinition\RectorDefinition;
+
+/**
+ * @see \Rector\DeadCode\Tests\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector\RemoveDuplicatedCaseInSwitchRectorTest
+ */
+final class RemoveDuplicatedCaseInSwitchRector extends AbstractRector
+{
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('2 following switch keys with identical  will be reduced to one result', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function run()
+    {
+        switch ($name) {
+             case 'clearHeader':
+                 return $this->modifyHeader($node, 'remove');
+             case 'clearAllHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case 'clearRawHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case '...':
+                 return 5;
+        }
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function run()
+    {
+        switch ($name) {
+             case 'clearHeader':
+                 return $this->modifyHeader($node, 'remove');
+             case 'clearAllHeaders':
+             case 'clearRawHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case '...':
+                 return 5;
+        }
+    }
+}
+CODE_SAMPLE
+            ),
+        ]);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNodeTypes(): array
+    {
+        return [Switch_::class];
+    }
+
+    /**
+     * @param Switch_ $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (count($node->cases) < 2) {
+            return null;
+        }
+
+        /** @var Node\Stmt\Case_|null $previousCase */
+        $previousCase = null;
+        foreach ($node->cases as $case) {
+            if ($previousCase && $this->areNodesEqual($case->stmts, $previousCase->stmts)) {
+                $previousCase->stmts = [];
+            }
+
+            $previousCase = $case;
+        }
+
+        return $node;
+    }
+}

packages/DeadCode/tests/Rector/Switch_/RemoveDuplicatedCaseInSwitchRector/Fixture/fixture.php.inc

@@ -0,0 +1,44 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector\Fixture;
+
+class SomeClass
+{
+    public function run()
+    {
+        switch ($name) {
+             case 'clearHeader':
+                 return $this->modifyHeader($node, 'remove');
+             case 'clearAllHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case 'clearRawHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case '...':
+                 return 5;
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector\Fixture;
+
+class SomeClass
+{
+    public function run()
+    {
+        switch ($name) {
+             case 'clearHeader':
+                 return $this->modifyHeader($node, 'remove');
+             case 'clearAllHeaders':
+             case 'clearRawHeaders':
+                 return $this->modifyHeader($node, 'replace');
+             case '...':
+                 return 5;
+        }
+    }
+}
+
+?>

packages/DeadCode/tests/Rector/Switch_/RemoveDuplicatedCaseInSwitchRector/RemoveDuplicatedCaseInSwitchRectorTest.php

@@ -0,0 +1,19 @@
+<?php declare(strict_types=1);
+
+namespace Rector\DeadCode\Tests\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector;
+
+use Rector\DeadCode\Rector\Switch_\RemoveDuplicatedCaseInSwitchRector;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class RemoveDuplicatedCaseInSwitchRectorTest extends AbstractRectorTestCase
+{
+    public function test(): void
+    {
+        $this->doTestFiles([__DIR__ . '/Fixture/fixture.php.inc']);
+    }
+
+    protected function getRectorClass(): string
+    {
+        return RemoveDuplicatedCaseInSwitchRector::class;
+    }
+}