Bugfix: Header with value "0" is being discarded

Author: Jefersson Nathan

src/functions/marshal_headers_from_sapi.php

@@ -46,6 +46,8 @@ function marshalHeadersFromSapi(array $server) : array
             $headers[$name] = $value;
             continue;
         }
+
+        $headers[$key] = $value;
     }
 
     return $headers;

test/ServerRequestFactoryTest.php

@@ -421,6 +421,18 @@ public function testFromGlobalsUsesCookieHeaderInsteadOfCookieSuperGlobal()
         $this->assertSame(['foo_bar' => 'baz'], $request->getCookieParams());
     }
 
+    /**
+     * @runInSeparateProcess
+     * @preserveGlobalState
+     */
+    public function testCreateFromGlobalsShouldPreserveKeysWhenCreatedWithAZeroValue()
+    {
+        $_SERVER['Accept'] = '0';
+
+        $request = ServerRequestFactory::fromGlobals();
+        $this->assertSame('0', $request->getHeaderLine('Accept'));
+    }
+
     /**
      * @runInSeparateProcess
      * @preserveGlobalState disabled