How to use the hoek.merge function in hoek

console.log(copy.x.b);      // results in 100

// merge(target, source, isNullOverride, isMergeArrays)

let target = { a: 1, b: 2 };
let source = { a: 0, c: 5 };
let source2 = { a: null, c: 5 };

Hoek.merge(target, source);         // results in {a: 0, b: 2, c: 5}
Hoek.merge(target, source2);        // results in {a: null, b: 2, c: 5}
Hoek.merge(target, source2, false); // results in {a: 1, b: 2, c: 5}

let targetArray = [1, 2, 3];
let sourceArray = [4, 5];

Hoek.merge(targetArray, sourceArray);              // results in [1, 2, 3, 4, 5]
Hoek.merge(targetArray, sourceArray, true, false); // results in [4, 5]

// applyToDefaults(defaults, options, isNullOverride)

let defaults = { host: "localhost", port: 8000 };
let options = { port: 8080 };

let config = Hoek.applyToDefaults(defaults, options); // results in { host: "localhost", port: 8080 }

defaults = { host: "localhost", port: 8000 };
let options1 = { host: null, port: 8080 };

config = Hoek.applyToDefaults(defaults, options1, true); // results in { host: null, port: 8080 }

// applyToDefaultsWithShallow(defaults, options, keys)

server.register(Bell, function (err) {

                    expect(err).to.not.exist();

                    var custom = Bell.providers.bitbucket();
                    Hoek.merge(custom, provider);

                    Mock.override('https://bitbucket.org/api/1.0/user', {
                        // source: https://confluence.atlassian.com/display/BITBUCKET/user+Endpoint
                        repositories: [{}],
                        user: {
                            first_name: 'Steve',
                            last_name: '',
                            username: 'steve_stevens'
                        }
                    });

                    server.auth.strategy('custom', 'bell', {
                        password: 'password',
                        isSecure: false,
                        clientId: 'twitter',
                        clientSecret: 'secret',

}

    if (get) {
      query[key] = data[key];
      return;
    }

    payload[key] = data[key];
  });

  var uri = url.parse(newPath, true);

  var newQuery = {};
  Hoek.merge(newQuery, socketRequest._query);
  Hoek.merge(newQuery, query);
  Hoek.merge(newQuery, uri.query);

  uri.query = newQuery;
  delete uri.search;

  // Auto map "Authorization" attribute to Authorization header
  // TODO: Make this configurable?
  var headerNames = ['Authorization'];
  headerNames.some(function(value) {
    return [value, value.toLowerCase()].some(function(header) {
      if (headers[header]) {
        return true;
      }
      if (payload[header]) {
        headers[header] = payload[header];
        return true;
      }

ES.CREATE(timer, function(record) {
    Hoek.merge(record, timer); // http://git.io/Amv6
    // delete the useless _prefixed fields returned by ES
    record.id = record._id;
    delete record._index;
    delete record._type;
    delete record._version;
    delete record.person;
    delete record._id
    reply(record);
  })
}

_sendMessages(callback) {
        let lineData = [];
        this._data.forEach((event) => {
            const lines = LineProtocol.format(event, this.config, this.schemas);
            lineData = lineData.concat(lines);
        });
        const wreckOptions = {
            payload: lineData.join('\n')
        };

        Hoek.merge(wreckOptions, this._settings.wreck, false);

        // Prevent this from user tampering
        wreckOptions.headers['content-type'] = 'text/plain';
        Wreck.request('post', this._endpoint, wreckOptions, callback);
    }
}

server.register(Bell, function (err) {

                    expect(err).to.not.exist();

                    var custom = Bell.providers.google();
                    Hoek.merge(custom, provider);

                    var profile = {
                        id: '1234567890',
                        displayName: 'steve smith',
                        name: {
                            givenName: 'steve',
                            familyName: 'smith'
                        },
                        emails: [
                            {
                                'type': 'account',
                                'value': 'steve@example.com'
                            }
                        ]
                    };

server.register(Bell, function (err) {

                    expect(err).to.not.exist();

                    var custom = Bell.providers.yahoo();
                    Hoek.merge(custom, provider);

                    var profile = {
                        profile: {
                            guid: '1234567890',
                            givenName: 'steve',
                            familyName: 'smith'
                        }
                    };

                    Mock.override('https://social.yahooapis.com/v1/user/', profile);

                    server.auth.strategy('custom', 'bell', {
                        password: 'password',
                        isSecure: false,
                        clientId: 'yahoo',
                        clientSecret: 'secret',

Client.prototype.getHeaders = function(_group, _path, _query, _headers) {
  return yarp({
    url: this.buildUrl(_group, _path, _query),
    headers: Hoek.merge(this.authHeaders, _headers)
  });
};

properties.forEach(function(messages) {
          Hoek.merge(merged_properties, messages);
        });
        resolve({content: merged_properties, locale: locale});

exports.register = function (plugin, options, next) {
  var settings = Hoek.clone(internals.defaults)
  Hoek.merge(settings, options)

  plugin.views({
    engines: settings.engines || {
      hbs: {
        module: Handlebars
      }
    },
    path: settings.basePath
  })

  plugin.route({
    method: 'GET',
    path: settings.endpoint + '/companies/{id}',
    config: handlers.company
  })