feat(testing): accept type-hinted requests as assertSent parameters

src/Http/Faking/MockClient.php

@@ -416,7 +416,22 @@ private function checkClosureAgainstResponses(callable $closure): bool
             return false;
         }
 
-        // Let's first check if the latest response resolves the callable
+        // Let's first check if the callable type-hints the latest request class.
+        // If so, we try to find the corresponding request in the recorded responses
+        // and call the callable accordingly. We will only fail if it returns `false`.
+
+        if ($fqcn = $this->getRequestClass($closure)) {
+            /** @var Response */
+            foreach ($this->getRecordedResponses() as $response) {
+                if (get_class($request = $response->getPendingRequest()->getRequest()) !== $fqcn) {
+                    continue;
+                }
+
+                return $closure($request, $response) !== false;
+            }
+        }
+
+        // Let's then check if the latest response resolves the callable
         // with a successful result.
 
         $lastResponse = $this->getLastResponse();
@@ -482,4 +497,25 @@ private function getRequestSentCount(): array
 
         return array_count_values($requests);
     }
+
+    /**
+     * Get the FQCN of the request class if type-hinted.
+     *
+     * @return class-string
+     */
+    private function getRequestClass(callable $closure): ?string
+    {
+        $reflection = new \ReflectionFunction($closure);
+        $parameters = $reflection->getParameters();
+
+        if (! ($fqcn = $parameters[0]->getType()?->getName())) {
+            return null;
+        }
+
+        if (! is_a($fqcn, Request::class, allow_string: true)) {
+            return null;
+        }
+
+        return $fqcn;
+    }
 }

tests/Unit/MockClientTest.php

@@ -2,10 +2,12 @@
 
 declare(strict_types=1);
 
+use Pest\Expectation;
 use Saloon\Http\Faking\MockClient;
 use Saloon\Http\Faking\MockResponse;
 use Saloon\Tests\Fixtures\Requests\UserRequest;
 use Saloon\Tests\Fixtures\Requests\ErrorRequest;
+use PHPUnit\Framework\ExpectationFailedException;
 use Saloon\Exceptions\NoMockResponseFoundException;
 use Saloon\Tests\Fixtures\Connectors\TestConnector;
 use Saloon\Tests\Fixtures\Exceptions\TestResponseException;
@@ -261,3 +263,36 @@
     $response = connector()->send(new UserRequest, $mockClient);
     $response->throw();
 });
+
+test('`assertSent` accepts the request class as a type-hint', function () {
+    $mockClient = new MockClient([
+        MockResponse::make(['name' => 'Sam']),
+    ]);
+
+    $request = new UserRequest;
+    $request->headers()->add('X-Foo', 'bar');
+
+    connector()->send($request, $mockClient);
+
+    $mockClient->assertSent(function (UserRequest $request) {
+        expect($request->headers()->all())->toMatchArray([
+            'X-Foo' => 'bar',
+        ]);
+    });
+});
+
+test('`assertSent` fails or succeeds depending on the closure result when the closure is type-hinted', function (mixed $returns, bool $shouldThrow) {
+    $mockClient = new MockClient([
+        MockResponse::make(['name' => 'Sam']),
+    ]);
+
+    connector()->send(new UserRequest, $mockClient);
+
+    expect(fn () => $mockClient->assertSent(fn (UserRequest $request) => $returns))
+        ->when($shouldThrow, fn (Expectation $e) => $e->toThrow(ExpectationFailedException::class))
+        ->when(! $shouldThrow, fn (Expectation $e) => $e->not->toThrow(ExpectationFailedException::class));
+})->with([
+    [false, true],
+    [true, false],
+    [null, false],
+]);