PropertyCreateMockToCreateStubRector

Change mock object property that is never mocked to createStub()

 use PHPUnit\Framework\TestCase;

 final class SomeTest extends TestCase
 {
-    private \PHPUnit\Framework\MockObject\MockObject $someServiceMock;
+    private \PHPUnit\Framework\MockObject\Stub\Stub $someServiceMock;

     protected function setUp(): void
     {
-        $this->someServiceMock = $this->createMock(SomeService::class);
+        $this->someServiceMock = $this->createStub(SomeService::class);
     }

     public function testOne(): void
     {
         $someObject = new SomeClass($this->someServiceMock);
     }

     public function testTwo(): void
     {
         $someObject = new AnotherClass($this->someServiceMock);
     }
 }

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\PHPUnit\PHPUnit120\Rector\Class_\PropertyCreateMockToCreateStubRector;

return RectorConfig::configure()
    ->withRules([
        PropertyCreateMockToCreateStubRector::class,
    ]);