Why so much indirection and abstraction when it can be done more simply and directly?

    const newData = notificationData.map(ev => {
        return {
            username   : ev.username,
            message    : ev.message.replace(/</g, '&lt;'),
            date       : new Date(ev.date * 1000).toGMTString(),
            displayName: ev.displayName,
            sender     : `https://example.com/users/${ev.username}`,
            source     : `https://example.com/${ev.sourceType}/${ev.sourceId}`,
            icon       : `${iconPrefix}${ev.sourceType}${iconSuffix}`
        }
    });