diff --git a/psalm.xml b/psalm.xml
index 9b0f03a..1f59fbb 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -17,6 +17,7 @@
         <DocblockTypeContradiction>
             <errorLevel type="suppress">
                 <file name="src/Message/ServerRequest.php" />
+                <file name="src/Message/Uri.php" />
             </errorLevel>
         </DocblockTypeContradiction>
         <MissingClosureParamType>
diff --git a/src/Message/Stream.php b/src/Message/Stream.php
index 4543e38..7bcd6f9 100644
--- a/src/Message/Stream.php
+++ b/src/Message/Stream.php
@@ -166,6 +166,7 @@ class Stream implements StreamInterface
      *     PHP $whence values for `fseek()`.  SEEK_SET: Set position equal to
      *     offset bytes SEEK_CUR: Set position to current location plus offset
      *     SEEK_END: Set position to end-of-stream plus offset.
+     * @return void
      * @throws \RuntimeException on failure.
      */
     public function seek($offset, $whence = SEEK_SET)
@@ -191,6 +192,7 @@ class Stream implements StreamInterface
      *
      * @see seek()
      * @link http://www.php.net/manual/en/function.fseek.php
+     * @return void
      * @throws \RuntimeException on failure.
      */
     public function rewind()
diff --git a/src/Message/UploadedFile.php b/src/Message/UploadedFile.php
index d5cfc9b..aa8094e 100644
--- a/src/Message/UploadedFile.php
+++ b/src/Message/UploadedFile.php
@@ -10,12 +10,19 @@ use Psr\Http\Message\UploadedFileInterface;
  */
 class UploadedFile implements UploadedFileInterface
 {
+    /** @var string */
     private $clientFilename;
+    /** @var string */
     private $clientMediaType;
+    /** @var int */
     private $error;
+    /** @var bool */
     private $moved = false;
+    /** @var int */
     private $size;
+    /** @var StreamInterface */
     private $stream;
+    /** @var string|null */
     private $tmpName;
 
     /**
@@ -57,10 +64,11 @@ class UploadedFile implements UploadedFileInterface
         $this->size = $size;
 
         if (file_exists($tmpName)) {
+            $this->stream = new Stream(fopen($tmpName, 'r'));
             $this->tmpName = $tmpName;
-            $this->stream = new Stream(fopen($tmpName, "r"));
         } else {
             $this->stream = new NullStream();
+            $this->tmpName = null;
         }
     }
 
@@ -82,8 +90,11 @@ class UploadedFile implements UploadedFileInterface
      */
     public function getStream()
     {
+        if ($this->tmpName === null) {
+            throw new \RuntimeException("Unable to read uploaded file.");
+        }
         if ($this->moved) {
-            throw new \RuntimeException("File has already been moved");
+            throw new \RuntimeException("File has already been moved.");
         }
         if (php_sapi_name() !== "cli" && !is_uploaded_file($this->tmpName)) {
             throw new \RuntimeException("File is not an uploaded file.");
@@ -105,6 +116,7 @@ class UploadedFile implements UploadedFileInterface
      * @see http://php.net/is_uploaded_file
      * @see http://php.net/move_uploaded_file
      * @param string $path Path to which to move the uploaded file.
+     * @return void
      * @throws \InvalidArgumentException if the $path specified is invalid.
      * @throws \RuntimeException on any error during the move operation, or on
      *     the second or subsequent call to the method.
diff --git a/src/Message/Uri.php b/src/Message/Uri.php
index 6feaffb..78007b8 100644
--- a/src/Message/Uri.php
+++ b/src/Message/Uri.php
@@ -40,36 +40,36 @@ class Uri implements UriInterface
     /**
      * @param string $uri A string representation of a URI.
      */
-    public function __construct($uri = "")
+    public function __construct(string $uri = '')
     {
-        if (is_string($uri) && $uri !== "") {
-            $parsed = parse_url($uri);
-            if ($parsed !== false) {
-                if (isset($parsed["scheme"])) {
-                    $this->scheme = $parsed["scheme"];
-                }
-                if (isset($parsed["host"])) {
-                    $this->host = strtolower($parsed["host"]);
-                }
-                if (isset($parsed["port"])) {
-                    $this->port = $parsed["port"];
-                }
-                if (isset($parsed["user"])) {
-                    $this->user = $parsed["user"];
-                }
-                if (isset($parsed["pass"])) {
-                    $this->password = $parsed["pass"];
-                }
-                if (isset($parsed["path"])) {
-                    $this->path = $parsed["path"];
-                }
-                if (isset($parsed["query"])) {
-                    $this->query = $parsed["query"];
-                }
-                if (isset($parsed["fragment"])) {
-                    $this->fragment = $parsed["fragment"];
-                }
-            }
+        $parsed = parse_url($uri);
+        if (!$parsed) {
+            return;
+        }
+
+        if (isset($parsed['scheme'])) {
+            $this->scheme = $parsed['scheme'];
+        }
+        if (isset($parsed['host'])) {
+            $this->host = strtolower($parsed['host']);
+        }
+        if (isset($parsed['port'])) {
+            $this->port = $parsed['port'];
+        }
+        if (isset($parsed['user'])) {
+            $this->user = $parsed['user'];
+        }
+        if (isset($parsed['pass'])) {
+            $this->password = $parsed['pass'];
+        }
+        if (isset($parsed['path'])) {
+            $this->path = $parsed['path'];
+        }
+        if (isset($parsed['query'])) {
+            $this->query = $parsed['query'];
+        }
+        if (isset($parsed['fragment'])) {
+            $this->fragment = $parsed['fragment'];
         }
     }
 
@@ -538,7 +538,7 @@ class Uri implements UriInterface
         $reserved = ':/?#[]@!$&\'()*+,;=';
         $reserved = preg_quote($reserved);
         $pattern = '~(?:%(?![a-fA-F0-9]{2}))|(?:[^%a-zA-Z0-9\-\.\_\~' . $reserved . ']{1})~';
-        $callback = function ($matches) {
+        $callback = function (array $matches): string {
             return urlencode($matches[0]);
         };
         return preg_replace_callback($pattern, $callback, $subject);
diff --git a/test/tests/unit/Message/UploadedFileTest.php b/test/tests/unit/Message/UploadedFileTest.php
index 09b65f6..bab21ee 100644
--- a/test/tests/unit/Message/UploadedFileTest.php
+++ b/test/tests/unit/Message/UploadedFileTest.php
@@ -40,7 +40,7 @@ class UploadedFileTest extends TestCase
 
     public function testGetStreamReturnsStreamInterface()
     {
-        $file = new UploadedFile("", "", 0, "", 0);
+        $file = new UploadedFile("", "", 0, $this->tmpName, 0);
         $this->assertInstanceOf(StreamInterface::class, $file->getStream());
     }
 
@@ -53,10 +53,11 @@ class UploadedFileTest extends TestCase
         $this->assertEquals($content, (string) $stream);
     }
 
-    public function testGetStreamReturnsEmptyStreamForNoFile()
+    public function testGetStreamThrowsRuntimeExceptionForNoFile()
     {
         $file = new UploadedFile("", "", 0, "", 0);
-        $this->assertTrue($file->getStream()->eof());
+        $this->expectException(RuntimeException::class);
+        $file->getStream();
     }
 
     public function testGetStreamThrowsExceptionAfterMoveTo()