fix empty strings returned from request body streams being interpreted as eof

Author: KurtThiemann

src/Psr18/Client.php

@@ -85,7 +85,10 @@ protected function initRequest(RequestInterface $request, ResponseHeaderParser $
 
         $ch->setopt(CURLOPT_UPLOAD, true);
         $ch->setopt(CURLOPT_READFUNCTION, function ($ch, $fd, $length) use ($requestBody) {
-            return $requestBody->read($length);
+            do {
+                $chunk = $requestBody->read($length);
+            } while ($chunk === "" && $requestBody->eof() === false);
+            return $chunk;
         });
 
         $ch->setopt(CURLOPT_WRITEFUNCTION, /** @throws Throwable */ function ($ch, $data) {

tests/HttpClientTest.php

@@ -144,6 +144,33 @@ public function testThrowRequestExceptionIfRequestBodyThrows(): void
         $this->client->sendRequest($request);
     }
 
+    public function testRequestBodyStreamCanReturnEmptyChunks(): void
+    {
+        $requestBody = new PredefinedChunkStream([
+            "something",
+            "",
+            "else"
+        ]);
+
+        $chunks = [];
+        $this->curlHandle->setOnAfterRead(function ($chunk) use (&$chunks) {
+            $chunks[] = $chunk;
+        });
+
+        $request = $this->requestFactory->createRequest("POST", "https://example.com")
+            ->withBody($requestBody);
+
+        $this->client->sendRequest($request);
+
+        // Last chunk is empty
+        $this->assertEmpty(array_pop($chunks));
+
+        // No empty chunks in between
+        foreach ($chunks as $chunk) {
+            $this->assertNotEmpty($chunk);
+        }
+    }
+
     #[TestWith([CURLE_COULDNT_CONNECT, "CURLE_COULDNT_CONNECT"], "CURLE_COULDNT_CONNECT")]
     #[TestWith([CURLE_COULDNT_RESOLVE_HOST, "CURLE_COULDNT_RESOLVE_HOST"], "CURLE_COULDNT_RESOLVE_HOST")]
     #[TestWith([CURLE_COULDNT_RESOLVE_PROXY, "CURLE_COULDNT_RESOLVE_PROXY"], "CURLE_COULDNT_RESOLVE_PROXY")]

tests/Stream/PredefinedChunkStream.php

@@ -126,7 +126,7 @@ public function isReadable(): bool
      */
     public function read(int $length): string
     {
-        while (strlen($this->buffer) === 0 && count($this->chunks) > 0) {
+        if (strlen($this->buffer) === 0 && count($this->chunks) > 0) {
             $chunk = array_shift($this->chunks);
             if ($chunk instanceof Throwable) {
                 throw $chunk;

tests/Util/TestCurlHandle.php

@@ -71,7 +71,7 @@ public function doExec(): string|bool
                 $chunk = $this->options[CURLOPT_READFUNCTION](null, $this->options[CURLOPT_INFILE] ?? null, 8192);
                 $this->requestBodySink?->write($chunk);
                 $uploaded += strlen($chunk);
-                $this->onAfterRead?->call($this);
+                $this->onAfterRead?->call($this, $chunk);
                 $this->progressUpdate(0, 0, $this->getRequestHeader("Content-Length") ?? 0, $uploaded);
             } while (strlen($chunk) > 0);
         }