feat(http): empty request values are converted to null (tempestphp#976)

Author: brendt

src/Tempest/Router/src/Mappers/PsrRequestToRequestMapper.php

@@ -42,6 +42,10 @@ public function map(mixed $from, mixed $to): array|object
             }
         }
 
+        $data = arr($data)
+            ->map(fn (mixed $value) => $value === '' ? null : $value)
+            ->toArray();
+
         $headersAsString = array_map(
             fn (array $items) => implode(',', $items),
             $from->getHeaders(),

tests/Fixtures/Modules/Posts/PostRequest.php

@@ -15,5 +15,5 @@ final class PostRequest implements Request
 
     public string $title;
 
-    public string $text;
+    public ?string $text;
 }

tests/Integration/Mapper/PsrRequestToRequestMapperTest.php

@@ -46,6 +46,22 @@ public function test_map_with(): void
         $this->assertEquals('b', $request->text);
         $this->assertEquals(['x-test' => 'test'], $request->headers);
     }
+    
+    public function test_empty_strings_are_converted_to_null(): void
+    {
+        $mapper = new PsrRequestToRequestMapper();
+
+        /** @var PostRequest $request */
+        $request = $mapper->map(
+            from: $this->http->makePsrRequest(
+                uri: '/',
+                body: ['title' => 'a', 'text' => ''],
+            ),
+            to: PostRequest::class,
+        );
+
+        $this->assertNull($request->text);
+    }
 
     public function test_map_with_with_missing_data(): void
     {