fix: allow integer values in float types

A float property/parameter will accept an integer value in PHP, even
when `strict_types` is enabled. PHPStan and Psalm also accept the case
below. To make it consistent, the mapper will now accept integer values
in float types.

```php
(new \CuyZ\Valinor\MapperBuilder())
    ->mapper()
    ->map('float', 42); // returns `42.0`
```

src/Mapper/Tree/Builder/TreeNode.php

@@ -8,6 +8,7 @@
 use CuyZ\Valinor\Mapper\Tree\Message\Message;
 use CuyZ\Valinor\Mapper\Tree\Node;
 use CuyZ\Valinor\Mapper\Tree\Shell;
+use CuyZ\Valinor\Type\FloatType;
 use Throwable;
 
 use function array_map;
@@ -30,6 +31,14 @@ final class TreeNode
 
     private function __construct(Shell $shell, mixed $value)
     {
+        // When the value is an integer and the type is a float, the value needs
+        // to be cast to float — this special case needs to be handled in case a
+        // node is not a *native* PHP float type (for instance a class property
+        // with a `@var float` annotation).
+        if ($shell->type() instanceof FloatType && is_int($value)) {
+            $value = (float)$value;
+        }
+
         $this->shell = $shell;
         $this->value = $value;
     }

src/Type/Types/NativeFloatType.php

@@ -12,6 +12,7 @@
 
 use function assert;
 use function is_float;
+use function is_integer;
 use function is_numeric;
 
 /** @internal */
@@ -21,7 +22,7 @@ final class NativeFloatType implements FloatType
 
     public function accepts(mixed $value): bool
     {
-        return is_float($value);
+        return is_float($value) || is_integer($value);
     }
 
     public function matches(Type $other): bool

tests/Integration/Mapping/Object/ScalarValuesMappingTest.php

@@ -21,6 +21,7 @@ public function test_values_are_mapped_properly(): void
         $source = [
             'boolean' => true,
             'float' => 42.404,
+            'floatWithInteger' => 42,
             'positiveFloatValue' => 42.404,
             'negativeFloatValue' => -42.404,
             'integer' => 1337,
@@ -50,6 +51,7 @@ public function test_values_are_mapped_properly(): void
 
             self::assertSame(true, $result->boolean);
             self::assertSame(42.404, $result->float);
+            self::assertSame(42.0, $result->floatWithInteger);
             self::assertSame(42.404, $result->positiveFloatValue); // @phpstan-ignore-line
             self::assertSame(-42.404, $result->negativeFloatValue); // @phpstan-ignore-line
             self::assertSame(1337, $result->integer);
@@ -89,6 +91,8 @@ class ScalarValues
 
     public float $float = -1.0;
 
+    public float $floatWithInteger = -1.0;
+
     /** @var 42.404 */
     public float $positiveFloatValue;
 
@@ -165,6 +169,7 @@ class ScalarValuesWithConstructor extends ScalarValues
     public function __construct(
         bool $boolean,
         float $float,
+        float $floatWithInteger,
         float $positiveFloatValue,
         float $negativeFloatValue,
         int $integer,
@@ -186,6 +191,7 @@ public function __construct(
     ) {
         $this->boolean = $boolean;
         $this->float = $float;
+        $this->floatWithInteger = $floatWithInteger;
         $this->positiveFloatValue = $positiveFloatValue;
         $this->negativeFloatValue = $negativeFloatValue;
         $this->integer = $integer;

tests/Integration/Mapping/Object/UnionValuesMappingTest.php

@@ -88,12 +88,12 @@ public function test_values_are_mapped_properly(): void
     public function test_invalid_value_is_not_casted_when_casting_mode_is_disabled(): void
     {
         try {
-            (new MapperBuilder())->mapper()->map('string|float', 42);
+            (new MapperBuilder())->mapper()->map('string|int', 42.404);
         } catch (MappingError $exception) {
             $error = $exception->node()->messages()[0];
 
             self::assertSame('1607027306', $error->code());
-            self::assertSame('Value 42 does not match any of `string`, `float`.', (string)$error);
+            self::assertSame('Value 42.404 does not match any of `string`, `int`.', (string)$error);
         }
     }
 }

tests/Unit/Type/Types/NativeFloatTypeTest.php

@@ -29,13 +29,13 @@ protected function setUp(): void
     public function test_accepts_correct_values(): void
     {
         self::assertTrue($this->floatType->accepts(42.1337));
+        self::assertTrue($this->floatType->accepts(404));
     }
 
     public function test_does_not_accept_incorrect_values(): void
     {
         self::assertFalse($this->floatType->accepts(null));
         self::assertFalse($this->floatType->accepts('Schwifty!'));
-        self::assertFalse($this->floatType->accepts(404));
         self::assertFalse($this->floatType->accepts(['foo' => 'bar']));
         self::assertFalse($this->floatType->accepts(false));
         self::assertFalse($this->floatType->accepts(new stdClass()));