Fix normalization header values by trimming in MessageTrait (#24)

Author: devanych

src/MessageTrait.php

@@ -22,6 +22,7 @@
 use function preg_match;
 use function sprintf;
 use function strtolower;
+use function trim;
 
 /**
  * Trait implementing the methods defined in `Psr\Http\Message\MessageInterface`.
@@ -371,6 +372,8 @@ private function registerProtocolVersion(string $protocol): void
     }
 
     /**
+     * @see https://tools.ietf.org/html/rfc7230#section-3.2
+     *
      * @param mixed $name
      * @return string
      * @throws InvalidArgumentException for invalid header name.
@@ -388,6 +391,8 @@ private function normalizeHeaderName($name): string
     }
 
     /**
+     * @see https://tools.ietf.org/html/rfc7230#section-3.2
+     *
      * @param mixed $value
      * @return array
      * @throws InvalidArgumentException for invalid header name.
@@ -402,16 +407,20 @@ private function normalizeHeaderValue($value): array
             );
         }
 
+        $normalizedValues = [];
+
         foreach ($value as $v) {
             if ((!is_string($v) && !is_numeric($v)) || !preg_match('/^[ \t\x21-\x7E\x80-\xFF]*$/D', (string) $v)) {
                 throw new InvalidArgumentException(sprintf(
                     '"%s" is not valid header value.',
                     (is_object($v) ? get_class($v) : (is_string($v) ? $v : gettype($v)))
                 ));
             }
+
+            $normalizedValues[] = trim((string) $v, " \t");
         }
 
-        return $value;
+        return $normalizedValues;
     }
 
     /**

tests/MessageTest.php

@@ -199,6 +199,28 @@ public function testGetHeaderLineNotFound(): void
         $this->assertSame('', $this->message->getHeaderLine('Name'));
     }
 
+    /**
+     * @return array
+     */
+    public function trimmedHeaderValuesProvider(): array
+    {
+        return [
+            [(new Message())->withHeader('Name', [" \t \tValue\t \t "])],
+            [(new Message())->withHeader('Name', " \t \tValue\t \t ")],
+            [(new Message())->withAddedHeader('Name', " \t \tValue\t \t ")],
+        ];
+    }
+
+    /**
+     * @dataProvider trimmedHeaderValuesProvider
+     */
+    public function testHeaderValuesAreTrimmed(Message $message): void
+    {
+        $this->assertSame(['Name' => ['Value']], $message->getHeaders());
+        $this->assertSame('Value', $message->getHeaderLine('name'));
+        $this->assertSame(['Value'], $message->getHeader('name'));
+    }
+
     /**
      * @return array
      */