tests: Add downloader and request tests

Author: aaronflorey

src/Downloader/Downloader.php

@@ -104,7 +104,7 @@ public function flush(?callable $callback = null): void
             }
         }
 
-        if (!\count($requests)) {
+        if (\count($requests) === 0) {
             return;
         }
 

src/Http/Request.php

@@ -122,4 +122,17 @@ public function getParseCallback(): Closure
     {
         return $this->parseCallback;
     }
+
+    public function getResponse(): ?Response
+    {
+        return $this->response;
+    }
+
+    public function withResponse(?Response $response): self
+    {
+        $clone = clone $this;
+        $clone->response = $response;
+
+        return $clone;
+    }
 }

tests/Downloader/DownloaderTest.php

@@ -333,4 +333,46 @@ public function testDontCallParseCallbackIfProcessedResponseWasDroppedByExtensio
 
         self::assertFalse($called);
     }
+
+    public function testDontSendRequestIfHasResponse(): void
+    {
+        $request = $this->makeRequest();
+        $request = $request->withResponse($this->makeResponse($request));
+
+        $this->downloader->prepare($request);
+        $this->downloader->flush();
+
+        $this->client->assertRequestWasNotSent($request);
+    }
+
+    public function testResponseDispatchedWhenNotSent(): void
+    {
+        $request = $this->makeRequest();
+        $request = $request->withResponse($this->makeResponse($request));
+
+        $this->downloader->prepare($request);
+        $this->dispatcher->assertNotDispatched(ResponseReceiving::NAME);
+
+        $this->downloader->flush();
+        $this->dispatcher->assertDispatched(
+            ResponseReceiving::NAME,
+            static fn (ResponseReceiving $event) => $event->response->getRequest()->getUri() === $request->getUri(),
+        );
+
+        $this->client->assertRequestWasNotSent($request);
+    }
+
+    public function testPassRequestsThroughRequestHandlersWhenHasResponse(): void
+    {
+        $request = $this->makeRequest();
+        $request = $request->withResponse($this->makeResponse($request));
+
+        $middleware = new FakeMiddleware();
+
+        $this->downloader
+            ->withMiddleware($middleware)
+            ->prepare($request);
+
+        $middleware->assertRequestHandled($request);
+    }
 }

tests/Http/RequestTest.php

@@ -106,6 +106,19 @@ public function testReturnsUnderlyingGuzzleRequest(): void
         self::assertSame('::request-uri::', (string) $request->getPsrRequest()->getUri());
     }
 
+    public function testAddingResponseDoesntMutateRequest(): void
+    {
+        $requestA = $this->makeRequest('::request-uri::');
+
+        $response = $this->makeResponse($requestA);
+
+        $requestB = $requestA->withResponse($response);
+
+        self::assertNotSame($requestA, $requestB);
+        self::assertNull($requestA->getResponse());
+        self::assertSame($response, $requestB->getResponse());
+    }
+
     protected function createDroppable(): DroppableInterface
     {
         return $this->makeRequest();