moveTo doesn't take null in first parameter, but should do it according to documentation

[AlexanderGulakov]

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch nightwatch@2.3.7 for the project I'm working on.

my test:
var agentName = process.env.AGENT_NAME;
var agentSession = Number(process.env.SESSION_IDX);
var agentSessionName = process.env.SESSION_NAME;
var agentNumber = process.env.AGENT_NUM;

client.include("SetTestExpectation_alert")

client.rtcEvent("Start", 'global')
.rtcProgress("Start")
.pause(agentNumber * 500);
var sec = 1000;
var roomUrl = "some_roomUrl"

client
.rtcInfo("process.env.RTC_RUN_COUNT " + process.env.RTC_RUN_COUNT)
.rtcInfo("RTC agent start - agent: %s room: %s", agentName, roomUrl)
.url(roomUrl)
.waitForElementVisible('#input-user-name', 120 * sec)
.pause(300) //wait for page render
.setValue('#input-user-name', agentName.replace(/-/g, ''))
.pause(300)
.click(".MuiButtonBase-root.MuiButton-root")
.pause(5000)
.useXpath()
.waitForElementVisible("//[text()='Join Now']", 120 * sec)
.pause(300)
.click("//[text()='Join Now']")
.rtcProgress("In " + roomUrl)

client
.rtcSetNetwork({
outgoing: {
packetloss: 5,
jitter: 50,
latency: 200,
bitrate: 5000
},
incoming: {
packetloss: 6,
jitter: 50,
latency: 200,
bitrate: 6000
}
});

client
.pause(30 * sec)
.useCss()
.moveTo(null, 110, 10)
.pause(30 * sec)

client
.useXpath()
.waitForElementVisible("//[text()='Disconnect']", 60 * sec)
.pause(300)
.click("//[text()='Disconnect']")
.pause(15 * sec)

LOGS:

→ Running command: moveTo (, 110, 10)

→ Error
Error while running .moveTo() protocol action: Unknown element: null

-->

Here is the diff that solved my problem:

index 83efe39..b63991e 100644
--- a/node_modules/nightwatch/lib/transport/selenium-webdriver/method-mappings.js
+++ b/node_modules/nightwatch/lib/transport/selenium-webdriver/method-mappings.js
@@ -1,6 +1,6 @@
 const {WebElement, Origin, By} = require('selenium-webdriver');
 const {Locator} = require('../../element');
-const {isString} = require('../../utils');
+const {isString,isNull} = require('../../utils');
 const fs = require('fs');
 const cdp = require('./cdp.js');
 
@@ -26,6 +26,10 @@ module.exports = class MethodMappings {
       return new WebElement(this.driver, webElementOrString);
     }
 
+    if (isNull(webElementOrString)) {
+      return new WebElement(this.driver, '');
+    }
+
     throw new Error(`Unknown element: ${webElementOrString}`);
   }
 
diff --git a/node_modules/nightwatch/lib/utils/index.js b/node_modules/nightwatch/lib/utils/index.js
index 18d1f35..63ad935 100644
--- a/node_modules/nightwatch/lib/utils/index.js
+++ b/node_modules/nightwatch/lib/utils/index.js
@@ -32,7 +32,8 @@ const PrimitiveTypes = {
   BOOLEAN: 'boolean',
   NUMBER: 'number',
   STRING: 'string',
-  UNDEFINED: 'undefined'
+  UNDEFINED: 'undefined',
+  NULL: null
 };
 
 class Utils {
@@ -72,6 +73,10 @@ class Utils {
     return !Utils.isUndefined(value);
   }
 
+  static isNull(value) {
+    return value === PrimitiveTypes.NULL;
+  }
+  
   static isES6AsyncFn(fn) {
     return Utils.isFunction(fn) && fn.constructor.name === 'AsyncFunction';
   }

This issue body was partially generated by patch-package.