Make Date and DateTime comparable

src/core/etl/src/Flow/ETL/PHP/Type/Logical/DateTimeType.php

@@ -32,6 +32,10 @@ public function isComparableWith(Type $type) : bool
             return true;
         }
 
+        if ($type instanceof DateType) {
+            return true;
+        }
+
         return false;
     }
 

src/core/etl/src/Flow/ETL/PHP/Type/Logical/DateType.php

@@ -32,6 +32,10 @@ public function isComparableWith(Type $type) : bool
             return true;
         }
 
+        if ($type instanceof DateTimeType) {
+            return true;
+        }
+
         return false;
     }
 

src/core/etl/tests/Flow/ETL/Tests/Unit/PHP/Type/Logical/DateTimeTypeTest.php

@@ -4,7 +4,7 @@
 
 namespace Flow\ETL\Tests\Unit\PHP\Type\Logical;
 
-use function Flow\ETL\DSL\{type_datetime, type_int};
+use function Flow\ETL\DSL\{type_date, type_datetime, type_int, type_null};
 use Flow\ETL\Tests\FlowTestCase;
 
 final class DateTimeTypeTest extends FlowTestCase
@@ -19,6 +19,14 @@ public function test_equals() : void
         );
     }
 
+    public function test_is_comparable() : void
+    {
+        self::assertTrue(type_datetime()->isComparableWith(type_datetime()));
+        self::assertTrue(type_datetime()->isComparableWith(type_date()));
+        self::assertTrue(type_datetime()->isComparableWith(type_null()));
+        self::assertFalse(type_datetime()->isComparableWith(type_int()));
+    }
+
     public function test_is_valid() : void
     {
         self::assertTrue(type_datetime(true)->isValid(null));

src/core/etl/tests/Flow/ETL/Tests/Unit/PHP/Type/Logical/DateTypeTest.php

@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Flow\ETL\Tests\Unit\PHP\Type\Logical;
+
+use function Flow\ETL\DSL\{type_date, type_datetime, type_int, type_null};
+use Flow\ETL\Tests\FlowTestCase;
+
+final class DateTypeTest extends FlowTestCase
+{
+    public function test_equals() : void
+    {
+        self::assertTrue(
+            type_date()->isEqual(type_date())
+        );
+        self::assertFalse(
+            type_date()->isEqual(type_int())
+        );
+    }
+
+    public function test_is_comparable() : void
+    {
+        self::assertTrue(type_date()->isComparableWith(type_datetime()));
+        self::assertTrue(type_date()->isComparableWith(type_date()));
+        self::assertTrue(type_date()->isComparableWith(type_null()));
+        self::assertFalse(type_date()->isComparableWith(type_int()));
+    }
+
+    public function test_is_valid() : void
+    {
+        self::assertTrue(type_date(true)->isValid(null));
+        self::assertFalse(type_date()->isValid(new \DateTimeImmutable()));
+        self::assertTrue(type_date()->isValid(new \DateTime('2024-12-01')));
+        self::assertFalse(type_date()->isValid('2020-01-01'));
+        self::assertFalse(type_date()->isValid('2020-01-01 00:00:00'));
+    }
+
+    public function test_merge_non_nullable_with_non_nullable() : void
+    {
+        self::assertFalse(type_date()->merge(type_date())->nullable());
+    }
+
+    public function test_merge_non_nullable_with_nullable() : void
+    {
+        self::assertTrue(type_date()->merge(type_date(true))->nullable());
+        self::assertTrue(type_date(true)->merge(type_date(false))->nullable());
+    }
+
+    public function test_merge_nullable_with_nullable() : void
+    {
+        self::assertTrue(type_date(true)->merge(type_date(true))->nullable());
+    }
+
+    public function test_to_string() : void
+    {
+        self::assertSame(
+            'date',
+            type_date()->toString()
+        );
+        self::assertSame(
+            '?date',
+            type_date(true)->toString()
+        );
+    }
+}