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<?php class KernelTestBase { protected function setUp(): void {} } class ConcreteTest extends KernelTestBase { protected function setUp() {} }
Output for 7.4.0 - 7.4.25, 8.0.0 - 8.0.12
Fatal error: Declaration of ConcreteTest::setUp() must be compatible with KernelTestBase::setUp(): void in /in/uHi7Q on line 8
Process exited with code 255.
Output for 7.3.0 - 7.3.32
Fatal error: Declaration of ConcreteTest::setUp() must be compatible with KernelTestBase::setUp(): void in /in/uHi7Q on line 9
Process exited with code 255.

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