fix(mapper): nullable datetime caster (tempestphp#974)

Author: brendt

src/Tempest/Mapper/src/Casters/DateTimeCaster.php

@@ -17,8 +17,7 @@
     public function __construct(
         private string $format = DATE_ATOM,
         private bool $immutable = true,
-    ) {
-    }
+    ) {}
 
     public static function fromProperty(PropertyReflector $property): DateTimeCaster
     {
@@ -30,8 +29,12 @@ public static function fromProperty(PropertyReflector $property): DateTimeCaster
         };
     }
 
-    public function cast(mixed $input): DateTimeInterface
+    public function cast(mixed $input): ?DateTimeInterface
     {
+        if (! $input) {
+            return null;
+        }
+
         if ($input instanceof DateTimeInterface) {
             return $input;
         }

src/Tempest/Mapper/src/Mappers/ArrayToObjectMapper.php

@@ -21,8 +21,7 @@
 {
     public function __construct(
         private CasterFactory $casterFactory,
-    ) {
-    }
+    ) {}
 
     public function canMap(mixed $from, mixed $to): bool
     {
@@ -93,7 +92,7 @@ public function map(mixed $from, mixed $to): object
             if ($value instanceof UnknownValue) {
                 $caster = $this->casterFactory->forProperty($property);
 
-                $value = $caster?->cast($from[$propertyName]) ?? $from[$propertyName];
+                $value = $caster ? $caster->cast($from[$propertyName]) : $from[$propertyName];
             }
 
             $property->setValue($object, $value);
@@ -145,7 +144,8 @@ private function resolveValueFromType(
         mixed $data,
         PropertyReflector $property,
         object $parent,
-    ): mixed {
+    ): mixed
+    {
         $type = $property->getType();
 
         if ($type->isBuiltIn()) {
@@ -155,7 +155,7 @@ private function resolveValueFromType(
         $caster = $this->casterFactory->forProperty($property);
 
         if (! is_array($data)) {
-            return $caster?->cast($data) ?? $data;
+            return $caster ? $caster->cast($data) : $data;
         }
 
         $data = $this->withParentRelations(
@@ -165,7 +165,7 @@ private function resolveValueFromType(
         );
 
         return $this->map(
-            from: $caster?->cast($data) ?? $data,
+            from: $caster ? $caster->cast($data) : $data,
             to: $type->getName(),
         );
     }
@@ -174,7 +174,8 @@ private function resolveValueFromArray(
         mixed $data,
         PropertyReflector $property,
         object $parent,
-    ): UnknownValue|array {
+    ): UnknownValue|array
+    {
         $type = $property->getIterableType();
 
         if ($type === null) {
@@ -192,7 +193,7 @@ private function resolveValueFromArray(
 
         foreach ($data as $key => $item) {
             if (! is_array($item)) {
-                $values[$key] = $caster?->cast($item) ?? $item;
+                $values[$key] = $caster ? $caster->cast($item) : $item;
 
                 continue;
             }
@@ -204,7 +205,7 @@ private function resolveValueFromArray(
             );
 
             $values[] = $this->map(
-                from: $caster?->cast($item) ?? $item,
+                from: $caster ? $caster->cast($item) : $item,
                 to: $type->getName(),
             );
         }
@@ -223,7 +224,8 @@ private function withParentRelations(
         ClassReflector $child,
         object $parent,
         array $data,
-    ): array {
+    ): array
+    {
         foreach ($child->getPublicProperties() as $property) {
             if ($property->getType()->getName() === $parent::class) {
                 $data[$property->getName()] = $parent;

tests/Integration/Mapper/Fixtures/ObjectWithBuiltInCasters.php

@@ -10,6 +10,8 @@
 
 final class ObjectWithBuiltInCasters
 {
+    public ?DateTimeImmutable $nullableDateTimeImmutable = null;
+
     public DateTimeImmutable $dateTimeObject;
 
     public DateTimeImmutable $dateTimeImmutable;

tests/Integration/Mapper/Mappers/ArrayToObjectMapperTestCase.php

@@ -65,6 +65,7 @@ public function test_default_values(): void
     public function test_built_in_casters(): void
     {
         $object = map([
+            'nullableDateTimeImmutable' => '',
             'dateTimeObject' => new DateTimeImmutable('2024-01-01 10:10:10'),
             'dateTimeImmutable' => '2024-01-01 10:10:10',
             'dateTime' => '2024-01-01 10:10:10',
@@ -78,6 +79,7 @@ public function test_built_in_casters(): void
         $this->assertSame('2024-01-01 10:10:10', $object->dateTimeImmutable->format('Y-m-d H:i:s'));
         $this->assertSame('2024-01-01 10:10:10', $object->dateTime->format('Y-m-d H:i:s'));
         $this->assertSame('2024-12-01 10:10:10', $object->dateTimeWithFormat->format('Y-m-d H:i:s'));
+        $this->assertNull($object->nullableDateTimeImmutable);
         $this->assertSame(true, $object->bool);
         $this->assertSame(0.1, $object->float);
         $this->assertSame(1, $object->int);