src/HttpAssert.php
public static function assertJson(
        $status,
        $contentType,
        $content,
        int $expected = self::STATUS_OK,
        string $message = ''
    ): Document
    {
        self::assertStatusCode($status, $expected, $content, $message);

        return self::assertContent($contentType, $content, self::JSON_MEDIA_TYPE, $message);
    }
public static function assertJson(
        $status,
        $contentType,
        $content,
        int $expected = self::STATUS_OK,
        string $message = ''
    ): Document
    {
        self::assertStatusCode($status, $expected, $content, $message);

        return self::assertContent($contentType, $content, self::JSON_MEDIA_TYPE, $message);
    }
Assert a JSON HTTP message with an expected status.

@param $status
@param $contentType
@param $content
@param int $expected
the expected HTTP status.
@param string $message
@return Document