From f8ebda92a8be264e2575d58b8bd83547d5da2c22 Mon Sep 17 00:00:00 2001
From: Max Hoogenbosch <mhoogenbosch@enrise.com>
Date: Fri, 3 Apr 2026 12:34:32 +0200
Subject: [PATCH 1/3] Add rule to convert phpunit methods to snake case

---
 .../Fixture/rename.php.inc                    | 37 +++++++
 .../PreferTestsWithSnakeCaseRectorTest.php    | 28 ++++++
 .../config/configured_rule.php                | 10 ++
 .../PreferTestsWithSnakeCaseRector.php        | 97 +++++++++++++++++++
 4 files changed, 172 insertions(+)
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php
 create mode 100644 rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php

diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
new file mode 100644
index 00000000..88f2c48c
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
@@ -0,0 +1,37 @@
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class RenameTest extends TestCase
+{
+    public function testMe()
+    {
+    }
+
+    public function testThisIsALongTestCase()
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class RenameTest extends TestCase
+{
+    public function test_me()
+    {
+    }
+
+    public function test_this_is_a_long_test_case()
+    {
+    }
+}
+
+?>
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
new file mode 100644
index 00000000..686af464
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector;
+
+use Iterator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class PreferTestsWithSnakeCaseRectorTest extends AbstractRectorTestCase
+{
+    #[DataProvider('provideData')]
+    public function test(string $filePath): void
+    {
+        $this->doTestFile($filePath);
+    }
+
+    public static function provideData(): Iterator
+    {
+        return self::yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    public function provideConfigFilePath(): string
+    {
+        return __DIR__ . '/config/configured_rule.php';
+    }
+}
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php
new file mode 100644
index 00000000..e7faaf99
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php
@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\PHPUnit\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->rule(PreferTestsWithSnakeCaseRector::class);
+};
diff --git a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php b/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php
new file mode 100644
index 00000000..2be20c1a
--- /dev/null
+++ b/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php
@@ -0,0 +1,97 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\PHPUnit\CodeQuality\Rector\ClassMethod;
+
+use PhpParser\Node;
+use PhpParser\Node\Stmt\ClassMethod;
+use Rector\PHPUnit\NodeAnalyzer\TestsNodeAnalyzer;
+use Rector\Rector\AbstractRector;
+use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
+use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
+
+/**
+ * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\PreferTestsWithSnakeCaseRectorTest
+ */
+final class PreferTestsWithSnakeCaseRector extends AbstractRector
+{
+    public function __construct(
+        private readonly TestsNodeAnalyzer $testsNodeAnalyzer,
+    ) {
+    }
+
+    public function getRuleDefinition(): RuleDefinition
+    {
+        return new RuleDefinition('Changes PHPUnit tests methods to snake case', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+use PHPUnit\Framework\TestCase;
+
+final class SomeClass extends TestCase
+{
+    public function testSomething()
+    {
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+use PHPUnit\Framework\TestCase;
+
+final class SomeClass extends TestCase
+{
+    public function test_something()
+    {
+    }
+}
+CODE_SAMPLE
+            ),
+        ]);
+    }
+
+    /**
+     * @return array<class-string<Node>>
+     */
+    public function getNodeTypes(): array
+    {
+        return [ClassMethod::class];
+    }
+
+    /**
+     * @param ClassMethod $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (! $this->testsNodeAnalyzer->isInTestClass($node)) {
+            return null;
+        }
+
+        if (! $this->testsNodeAnalyzer->isTestClassMethod($node)) {
+            return null;
+        }
+
+        $currentName = $node->name->toString();
+        $newName = $this->toSnakeCase($currentName);
+
+        if ($currentName === $newName) {
+            return null;
+        }
+
+        $node->name = new Node\Identifier($newName);
+
+        return $node;
+    }
+
+    public function toSnakeCase(string $value): string
+    {
+        if (ctype_lower($value)) {
+            return $value;
+        }
+
+        $value = (string) preg_replace('/\s+/u', '', ucwords($value));
+        $value = (string) preg_replace('/(.)(?=[A-Z])/u', '$1_', $value);
+
+        return strtolower($value);
+    }
+}

From cc3684d0ef6b9e62cf98a0230374bc2886e18bb8 Mon Sep 17 00:00:00 2001
From: Max Hoogenbosch <mhoogenbosch@enrise.com>
Date: Fri, 3 Apr 2026 12:48:10 +0200
Subject: [PATCH 2/3] Add rule to convert phpunit methods to camel case

---
 .../Fixture/rename.php.inc                    | 37 ++++++++
 .../PreferTestsWithCamelCaseRectorTest.php    | 28 ++++++
 .../config/configured_rule.php                | 10 ++
 .../PreferTestsWithCamelCaseRector.php        | 93 +++++++++++++++++++
 4 files changed, 168 insertions(+)
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
 create mode 100644 rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php
 create mode 100644 rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php

diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
new file mode 100644
index 00000000..2151c12c
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
@@ -0,0 +1,37 @@
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class RenameTest extends TestCase
+{
+    public function test_me()
+    {
+    }
+
+    public function test_this_is_a_long_test_case()
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class RenameTest extends TestCase
+{
+    public function testMe()
+    {
+    }
+
+    public function testThisIsALongTestCase()
+    {
+    }
+}
+
+?>
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
new file mode 100644
index 00000000..507409a0
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector;
+
+use Iterator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class PreferTestsWithCamelCaseRectorTest extends AbstractRectorTestCase
+{
+    #[DataProvider('provideData')]
+    public function test(string $filePath): void
+    {
+        $this->doTestFile($filePath);
+    }
+
+    public static function provideData(): Iterator
+    {
+        return self::yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    public function provideConfigFilePath(): string
+    {
+        return __DIR__ . '/config/configured_rule.php';
+    }
+}
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php
new file mode 100644
index 00000000..ac1d7c14
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php
@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\PHPUnit\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->rule(PreferTestsWithCamelCaseRector::class);
+};
diff --git a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php b/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php
new file mode 100644
index 00000000..a70e5062
--- /dev/null
+++ b/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php
@@ -0,0 +1,93 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\PHPUnit\CodeQuality\Rector\ClassMethod;
+
+use PhpParser\Node;
+use PhpParser\Node\Stmt\ClassMethod;
+use Rector\PHPUnit\NodeAnalyzer\TestsNodeAnalyzer;
+use Rector\Rector\AbstractRector;
+use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
+use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
+
+/**
+ * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\PreferTestsWithCamelCaseRectorTest
+ */
+final class PreferTestsWithCamelCaseRector extends AbstractRector
+{
+    public function __construct(
+        private readonly TestsNodeAnalyzer $testsNodeAnalyzer,
+    ) {
+    }
+
+    public function getRuleDefinition(): RuleDefinition
+    {
+        return new RuleDefinition('Changes PHPUnit tests methods to camel case', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+use PHPUnit\Framework\TestCase;
+
+final class SomeClass extends TestCase
+{
+    public function test_something()
+    {
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+use PHPUnit\Framework\TestCase;
+
+final class SomeClass extends TestCase
+{
+    public function testSomething()
+    {
+    }
+}
+CODE_SAMPLE
+            ),
+        ]);
+    }
+
+    /**
+     * @return array<class-string<Node>>
+     */
+    public function getNodeTypes(): array
+    {
+        return [ClassMethod::class];
+    }
+
+    /**
+     * @param ClassMethod $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (! $this->testsNodeAnalyzer->isInTestClass($node)) {
+            return null;
+        }
+
+        if (! $this->testsNodeAnalyzer->isTestClassMethod($node)) {
+            return null;
+        }
+
+        $currentName = $node->name->toString();
+        $newName = $this->toCamelCase($currentName);
+
+        if ($currentName === $newName) {
+            return null;
+        }
+
+        $node->name = new Node\Identifier($newName);
+
+        return $node;
+    }
+
+    public function toCamelCase(string $value): string
+    {
+        $words = explode(' ', str_replace(['-', '_'], ' ', $value));
+        $words = array_map(fn (string $word) => ucfirst($word), $words);
+
+        return lcfirst(implode($words));
+    }
+}

From 2fdf38bfbc15a1f24cb9aca5c2cd2678d0c5e933 Mon Sep 17 00:00:00 2001
From: Tomas Votruba <tomas.vot@gmail.com>
Date: Fri, 26 Jun 2026 11:32:51 +0200
Subject: [PATCH 3/3] address review: use Class_ node type, skip rename on
 existing method name collision

---
 .../Fixture/rename.php.inc                    |  4 +-
 .../Fixture/skip_existing_name.php.inc        | 16 +++++++
 .../PreferTestsWithCamelCaseRectorTest.php    |  2 +-
 .../config/configured_rule.php                |  2 +-
 .../Fixture/rename.php.inc                    |  4 +-
 .../Fixture/skip_existing_name.php.inc        | 16 +++++++
 .../PreferTestsWithSnakeCaseRectorTest.php    |  2 +-
 .../config/configured_rule.php                |  2 +-
 .../PreferTestsWithCamelCaseRector.php        | 46 ++++++++++++-------
 .../PreferTestsWithSnakeCaseRector.php        | 44 ++++++++++++------
 10 files changed, 99 insertions(+), 39 deletions(-)
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc (65%)
 create mode 100644 rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/skip_existing_name.php.inc
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php (86%)
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithCamelCaseRector/config/configured_rule.php (70%)
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc (65%)
 create mode 100644 rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/skip_existing_name.php.inc
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php (86%)
 rename rules-tests/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithSnakeCaseRector/config/configured_rule.php (70%)
 rename rules/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithCamelCaseRector.php (54%)
 rename rules/CodeQuality/Rector/{ClassMethod => Class_}/PreferTestsWithSnakeCaseRector.php (58%)

diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
similarity index 65%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
index 2151c12c..415cd038 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/rename.php.inc
@@ -1,6 +1,6 @@
 <?php
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\Fixture;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector\Fixture;
 
 use PHPUnit\Framework\TestCase;
 
@@ -19,7 +19,7 @@ final class RenameTest extends TestCase
 -----
 <?php
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\Fixture;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector\Fixture;
 
 use PHPUnit\Framework\TestCase;
 
diff --git a/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/skip_existing_name.php.inc b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/skip_existing_name.php.inc
new file mode 100644
index 00000000..c001f833
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/Fixture/skip_existing_name.php.inc
@@ -0,0 +1,16 @@
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class SkipExistingNameTest extends TestCase
+{
+    public function test_me()
+    {
+    }
+
+    public function testMe()
+    {
+    }
+}
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
similarity index 86%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
index 507409a0..62b56edf 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/PreferTestsWithCamelCaseRectorTest.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector;
 
 use Iterator;
 use PHPUnit\Framework\Attributes\DataProvider;
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/config/configured_rule.php
similarity index 70%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/config/configured_rule.php
index ac1d7c14..641703e9 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector/config/configured_rule.php
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector/config/configured_rule.php
@@ -3,7 +3,7 @@
 declare(strict_types=1);
 
 use Rector\Config\RectorConfig;
-use Rector\PHPUnit\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector;
+use Rector\PHPUnit\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector;
 
 return static function (RectorConfig $rectorConfig): void {
     $rectorConfig->rule(PreferTestsWithCamelCaseRector::class);
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
similarity index 65%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
index 88f2c48c..4a25ebed 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/rename.php.inc
@@ -1,6 +1,6 @@
 <?php
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\Fixture;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector\Fixture;
 
 use PHPUnit\Framework\TestCase;
 
@@ -19,7 +19,7 @@ final class RenameTest extends TestCase
 -----
 <?php
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\Fixture;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector\Fixture;
 
 use PHPUnit\Framework\TestCase;
 
diff --git a/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/skip_existing_name.php.inc b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/skip_existing_name.php.inc
new file mode 100644
index 00000000..748670a0
--- /dev/null
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/Fixture/skip_existing_name.php.inc
@@ -0,0 +1,16 @@
+<?php
+
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector\Fixture;
+
+use PHPUnit\Framework\TestCase;
+
+final class SkipExistingNameTest extends TestCase
+{
+    public function testMe()
+    {
+    }
+
+    public function test_me()
+    {
+    }
+}
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
similarity index 86%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
index 686af464..2a21d476 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/PreferTestsWithSnakeCaseRectorTest.php
@@ -2,7 +2,7 @@
 
 declare(strict_types=1);
 
-namespace Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector;
+namespace Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector;
 
 use Iterator;
 use PHPUnit\Framework\Attributes\DataProvider;
diff --git a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/config/configured_rule.php
similarity index 70%
rename from rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php
rename to rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/config/configured_rule.php
index e7faaf99..0232f132 100644
--- a/rules-tests/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector/config/configured_rule.php
+++ b/rules-tests/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector/config/configured_rule.php
@@ -3,7 +3,7 @@
 declare(strict_types=1);
 
 use Rector\Config\RectorConfig;
-use Rector\PHPUnit\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector;
+use Rector\PHPUnit\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector;
 
 return static function (RectorConfig $rectorConfig): void {
     $rectorConfig->rule(PreferTestsWithSnakeCaseRector::class);
diff --git a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php b/rules/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector.php
similarity index 54%
rename from rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php
rename to rules/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector.php
index a70e5062..0a4d5f29 100644
--- a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithCamelCaseRector.php
+++ b/rules/CodeQuality/Rector/Class_/PreferTestsWithCamelCaseRector.php
@@ -2,17 +2,17 @@
 
 declare(strict_types=1);
 
-namespace Rector\PHPUnit\CodeQuality\Rector\ClassMethod;
+namespace Rector\PHPUnit\CodeQuality\Rector\Class_;
 
 use PhpParser\Node;
-use PhpParser\Node\Stmt\ClassMethod;
+use PhpParser\Node\Stmt\Class_;
 use Rector\PHPUnit\NodeAnalyzer\TestsNodeAnalyzer;
 use Rector\Rector\AbstractRector;
 use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
 use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
 
 /**
- * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithCamelCaseRector\PreferTestsWithCamelCaseRectorTest
+ * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithCamelCaseRector\PreferTestsWithCamelCaseRectorTest
  */
 final class PreferTestsWithCamelCaseRector extends AbstractRector
 {
@@ -23,7 +23,7 @@ public function __construct(
 
     public function getRuleDefinition(): RuleDefinition
     {
-        return new RuleDefinition('Changes PHPUnit tests methods to camel case', [
+        return new RuleDefinition('Changes PHPUnit test methods to camel case', [
             new CodeSample(
                 <<<'CODE_SAMPLE'
 use PHPUnit\Framework\TestCase;
@@ -55,11 +55,11 @@ public function testSomething()
      */
     public function getNodeTypes(): array
     {
-        return [ClassMethod::class];
+        return [Class_::class];
     }
 
     /**
-     * @param ClassMethod $node
+     * @param Class_ $node
      */
     public function refactor(Node $node): ?Node
     {
@@ -67,26 +67,40 @@ public function refactor(Node $node): ?Node
             return null;
         }
 
-        if (! $this->testsNodeAnalyzer->isTestClassMethod($node)) {
-            return null;
-        }
+        $hasChanged = false;
 
-        $currentName = $node->name->toString();
-        $newName = $this->toCamelCase($currentName);
+        foreach ($node->getMethods() as $classMethod) {
+            if (! $this->testsNodeAnalyzer->isTestClassMethod($classMethod)) {
+                continue;
+            }
 
-        if ($currentName === $newName) {
-            return null;
+            $currentName = $classMethod->name->toString();
+            $newName = $this->toCamelCase($currentName);
+
+            if ($currentName === $newName) {
+                continue;
+            }
+
+            // avoid name collision with an existing method
+            if ($node->getMethod($newName) instanceof Node) {
+                continue;
+            }
+
+            $classMethod->name = new Node\Identifier($newName);
+            $hasChanged = true;
         }
 
-        $node->name = new Node\Identifier($newName);
+        if ($hasChanged === false) {
+            return null;
+        }
 
         return $node;
     }
 
-    public function toCamelCase(string $value): string
+    private function toCamelCase(string $value): string
     {
         $words = explode(' ', str_replace(['-', '_'], ' ', $value));
-        $words = array_map(fn (string $word) => ucfirst($word), $words);
+        $words = array_map(fn (string $word): string => ucfirst($word), $words);
 
         return lcfirst(implode($words));
     }
diff --git a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php b/rules/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector.php
similarity index 58%
rename from rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php
rename to rules/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector.php
index 2be20c1a..6e5a3838 100644
--- a/rules/CodeQuality/Rector/ClassMethod/PreferTestsWithSnakeCaseRector.php
+++ b/rules/CodeQuality/Rector/Class_/PreferTestsWithSnakeCaseRector.php
@@ -2,17 +2,17 @@
 
 declare(strict_types=1);
 
-namespace Rector\PHPUnit\CodeQuality\Rector\ClassMethod;
+namespace Rector\PHPUnit\CodeQuality\Rector\Class_;
 
 use PhpParser\Node;
-use PhpParser\Node\Stmt\ClassMethod;
+use PhpParser\Node\Stmt\Class_;
 use Rector\PHPUnit\NodeAnalyzer\TestsNodeAnalyzer;
 use Rector\Rector\AbstractRector;
 use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
 use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
 
 /**
- * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\ClassMethod\PreferTestsWithSnakeCaseRector\PreferTestsWithSnakeCaseRectorTest
+ * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\PreferTestsWithSnakeCaseRector\PreferTestsWithSnakeCaseRectorTest
  */
 final class PreferTestsWithSnakeCaseRector extends AbstractRector
 {
@@ -23,7 +23,7 @@ public function __construct(
 
     public function getRuleDefinition(): RuleDefinition
     {
-        return new RuleDefinition('Changes PHPUnit tests methods to snake case', [
+        return new RuleDefinition('Changes PHPUnit test methods to snake case', [
             new CodeSample(
                 <<<'CODE_SAMPLE'
 use PHPUnit\Framework\TestCase;
@@ -55,11 +55,11 @@ public function test_something()
      */
     public function getNodeTypes(): array
     {
-        return [ClassMethod::class];
+        return [Class_::class];
     }
 
     /**
-     * @param ClassMethod $node
+     * @param Class_ $node
      */
     public function refactor(Node $node): ?Node
     {
@@ -67,23 +67,37 @@ public function refactor(Node $node): ?Node
             return null;
         }
 
-        if (! $this->testsNodeAnalyzer->isTestClassMethod($node)) {
-            return null;
-        }
+        $hasChanged = false;
 
-        $currentName = $node->name->toString();
-        $newName = $this->toSnakeCase($currentName);
+        foreach ($node->getMethods() as $classMethod) {
+            if (! $this->testsNodeAnalyzer->isTestClassMethod($classMethod)) {
+                continue;
+            }
 
-        if ($currentName === $newName) {
-            return null;
+            $currentName = $classMethod->name->toString();
+            $newName = $this->toSnakeCase($currentName);
+
+            if ($currentName === $newName) {
+                continue;
+            }
+
+            // avoid name collision with an existing method
+            if ($node->getMethod($newName) instanceof Node) {
+                continue;
+            }
+
+            $classMethod->name = new Node\Identifier($newName);
+            $hasChanged = true;
         }
 
-        $node->name = new Node\Identifier($newName);
+        if ($hasChanged === false) {
+            return null;
+        }
 
         return $node;
     }
 
-    public function toSnakeCase(string $value): string
+    private function toSnakeCase(string $value): string
     {
         if (ctype_lower($value)) {
             return $value;