chore: major code cleanup and type safety using phpstan

tests/Form/Model/AcceptedVouchersTest.php

@@ -26,8 +26,8 @@ class AcceptedVouchersTest extends TestCase
             amount: 100.00
         ));
 
-        $this->assertEquals(150.0, $acceptedVouchers->getTotalDiscount());
-        $this->assertCount(2, $acceptedVouchers->getVouchers());
+        self::assertEquals(150.0, $acceptedVouchers->getTotalDiscount());
+        self::assertCount(2, $acceptedVouchers->getVouchers());
     }
 
     public function testFilterVouchersByType(): void
@@ -52,17 +52,17 @@ class AcceptedVouchersTest extends TestCase
             amount: 75.00
         ));
 
-        $this->assertCount(1, $acceptedVouchers->getPromotionalVouchers());
-        $this->assertCount(1, $acceptedVouchers->getPurchaseVouchers());
-        $this->assertCount(1, $acceptedVouchers->getGoodwillVouchers());
+        self::assertCount(1, $acceptedVouchers->getPromotionalVouchers());
+        self::assertCount(1, $acceptedVouchers->getPurchaseVouchers());
+        self::assertCount(1, $acceptedVouchers->getGoodwillVouchers());
     }
 
     public function testHasVouchersReturnsFalseWhenEmpty(): void
     {
         $acceptedVouchers = new AcceptedVouchersDto();
 
-        $this->assertFalse($acceptedVouchers->hasVouchers());
-        $this->assertEquals(0, $acceptedVouchers->count());
+        self::assertFalse($acceptedVouchers->hasVouchers());
+        self::assertEquals(0, $acceptedVouchers->count());
     }
 
     public function testHasVouchersReturnsTrueWhenNotEmpty(): void
@@ -75,8 +75,8 @@ class AcceptedVouchersTest extends TestCase
             amount: 50.00
         ));
 
-        $this->assertTrue($acceptedVouchers->hasVouchers());
-        $this->assertEquals(1, $acceptedVouchers->count());
+        self::assertTrue($acceptedVouchers->hasVouchers());
+        self::assertEquals(1, $acceptedVouchers->count());
     }
 
     public function testFloatPrecisionHandling(): void
@@ -102,6 +102,6 @@ class AcceptedVouchersTest extends TestCase
         ));
 
         // Should be exactly 100.00 with proper rounding
-        $this->assertEquals(100.0, $acceptedVouchers->getTotalDiscount());
+        self::assertEquals(100.0, $acceptedVouchers->getTotalDiscount());
     }
 }

tests/Form/Model/BookingDtoTest.php

@@ -24,9 +24,9 @@ class BookingDtoTest extends TestCase
 
         $bookingDto = new BookingDto($travel, 1);
 
-        $this->assertInstanceOf(BookingDto::class, $bookingDto);
-        $this->assertSame($travel, $bookingDto->travel);
-        $this->assertSame(BookingDto::MODE_CREATE, $bookingDto->getMode());
+        self::assertInstanceOf(BookingDto::class, $bookingDto);
+        self::assertSame($travel, $bookingDto->travel);
+        self::assertSame(BookingDto::MODE_CREATE, $bookingDto->getMode());
     }
 
     public function testUnserializeHandlesIntTravelId(): void
@@ -40,8 +40,8 @@ class BookingDtoTest extends TestCase
         $serialized = serialize($dto);
         $restored = unserialize($serialized);
 
-        $this->assertInstanceOf(BookingDto::class, $restored);
-        $this->assertSame(42, $restored->travel->id);
+        self::assertInstanceOf(BookingDto::class, $restored);
+        self::assertSame(42, $restored->travel->id);
     }
 
     public function testUnserializeHandlesLegacyTravelObject(): void
@@ -60,7 +60,7 @@ class BookingDtoTest extends TestCase
         $dto = new BookingDto(new Travel(), 1);
         $dto->__unserialize($data);
 
-        $this->assertSame($travel, $dto->travel);
-        $this->assertSame(42, $dto->travel->id);
+        self::assertSame($travel, $dto->travel);
+        self::assertSame(42, $dto->travel->id);
     }
 }

tests/Form/Model/ParticipantDtoTest.php

@@ -15,7 +15,7 @@ class ParticipantDtoTest extends TestCase
         $participant = new ParticipantDto();
         $participant->dateOfBirth = null;
 
-        $this->assertNull($participant->getAge());
+        self::assertNull($participant->getAge());
     }
 
     public function testGetAgeCalculatesCurrentAgeWhenNoReferenceDateProvided(): void
@@ -26,7 +26,7 @@ class ParticipantDtoTest extends TestCase
         $expectedAge = (new \DateTimeImmutable())->diff($participant->dateOfBirth)->y;
         $actualAge = $participant->getAge();
 
-        $this->assertEquals($expectedAge, $actualAge);
+        self::assertEquals($expectedAge, $actualAge);
     }
 
     public function testGetAgeCalculatesAgeAtSpecificReferenceDate(): void
@@ -37,7 +37,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertEquals(33, $result); // Still 33 years old
+        self::assertEquals(33, $result); // Still 33 years old
     }
 
     public function testGetAgeCalculatesAgeAtSpecificReferenceDateAfterBirthday(): void
@@ -48,7 +48,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertEquals(34, $result); // Now 34 years old
+        self::assertEquals(34, $result); // Now 34 years old
     }
 
     public function testGetAgeCalculatesAgeForInsuranceEligibilityScenario(): void
@@ -61,7 +61,7 @@ class ParticipantDtoTest extends TestCase
         $result = $participant->getAge($travelStartDate);
 
         // On 2024-08-01, they are still 34 (birthday not yet reached)
-        $this->assertEquals(34, $result);
+        self::assertEquals(34, $result);
     }
 
     public function testGetAgeCalculatesAgeForInsuranceEligibilityScenarioAfterBirthday(): void
@@ -74,7 +74,7 @@ class ParticipantDtoTest extends TestCase
         $result = $participant->getAge($travelStartDate);
 
         // On 2024-12-26, they just turned 35
-        $this->assertEquals(35, $result);
+        self::assertEquals(35, $result);
     }
 
     public function testGetAgeHandlesLeapYearScenarios(): void
@@ -86,7 +86,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertEquals(22, $result); // Still 22, birthday is technically next day
+        self::assertEquals(22, $result); // Still 22, birthday is technically next day
     }
 
     public function testGetAgeReturnsNullWithReferenceDateWhenDateOfBirthIsNull(): void
@@ -97,7 +97,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertNull($result);
+        self::assertNull($result);
     }
 
     public function testGetAgeWithYoungParticipant(): void
@@ -109,7 +109,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertEquals(4, $result);
+        self::assertEquals(4, $result);
     }
 
     public function testGetAgeWithElderlyParticipant(): void
@@ -121,7 +121,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getAge($referenceDate);
 
-        $this->assertEquals(84, $result);
+        self::assertEquals(84, $result);
     }
 
     public function testHasInsuranceReturnsFalseWhenNoInsuranceSelected(): void
@@ -131,7 +131,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->hasInsuranceSelected();
 
-        $this->assertFalse($result);
+        self::assertFalse($result);
     }
 
     public function testHasInsuranceReturnsTrueWhenInsuranceSelected(): void
@@ -141,7 +141,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->hasInsuranceSelected();
 
-        $this->assertTrue($result);
+        self::assertTrue($result);
     }
 
     public function testGetInsuranceLabelReturnsNullWhenNoInsurance(): void
@@ -151,7 +151,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getInsuranceLabel();
 
-        $this->assertNull($result);
+        self::assertNull($result);
     }
 
     public function testGetInsuranceLabelReturnsLabelWhenInsuranceSelected(): void
@@ -161,7 +161,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getInsuranceLabel();
 
-        $this->assertEquals('Reise-Rücktritt', $result);
+        self::assertEquals('Reise-Rücktritt', $result);
     }
 
     public function testGetInsurancePriceReturnsZeroWhenNoInsurance(): void
@@ -171,7 +171,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getInsurancePrice();
 
-        $this->assertEquals(0.0, $result);
+        self::assertEquals(0.0, $result);
     }
 
     public function testGetInsurancePriceReturnsPriceWhenInsuranceSelected(): void
@@ -181,7 +181,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getInsurancePrice();
 
-        $this->assertEquals(25.50, $result);
+        self::assertEquals(25.50, $result);
     }
 
     public function testGetInsurancePriceReturnsZeroWhenInsuranceHasNullPrice(): void
@@ -193,7 +193,7 @@ class ParticipantDtoTest extends TestCase
 
         $result = $participant->getInsurancePrice();
 
-        $this->assertEquals(0.0, $result);
+        self::assertEquals(0.0, $result);
     }
 
     private function createInsurance(string $label = 'Test Insurance', float $price = 10.0): Insurance