Problem in writing step definitions - Cucumber & Appium on JavaScript

Question

I am working on a project that is more like a proof of concept. A POC for me actually, as I am sure that it thas been done before.

I am trying to work with Cucumber.js, Appium Server / Client, Node and Javascript on Visual Studio Code.

A little bit of background. I am new to Javascript but not entirely new to BDD / Cucumber and automated testing wit Appium.

I have hit a roadblock just at beginning the project and I can't understand what is wrong or where to go from here. Searching the internet has not got me anywhere - probably not searching in the right places r with the right keywords.

Let me explain. I have created feature files within a workspace in Visual Studio code as follows

 Feature: Change Font Size

  Scenario: Set Font Size to Default
    Given that I am on Font Size option
    When I click the default option
    Then The font size should be set to default

  Scenario: Set Font Size to Small
    Given that I am on Font Size option
    When I click the small option
    Then The font size should be set to small

I have generated glue code by using the following command

Windows PowerShell
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PS C:\Projects\VisualStudioCode\CucumberAppium> node_modules/.bin/cucumber-js

All good as this generates the glue code / step definitions that I add to my js file. My js file looks as follows. This has been picked up AS IS after running the cucumber-js command (mentioned above)

const {Given,When,Then} = require('cucumber');

Given('that I am on Font Size option', function () {
    // Write code here that turns the phrase above into concrete actions
    return 'pending';
});

When('I click the default option', function () {
    // Write code here that turns the phrase above into concrete actions
    return 'pending';
});

Then('The font size should be set to default', function () {
    // Write code here that turns the phrase above into concrete actions
    return 'pending';
});

When('I click the small option', function () {
    // Write code here that turns the phrase above into concrete actions
    return 'pending';
});

Then('The font size should be set to small', function () {
    // Write code here that turns the phrase above into concrete actions
    return 'pending';
});

I haven't added any code yet, but when I run this Run->Run without debugging then the very least I expect to happen is NOTHING - since there is no code.

But I am getting an error (mentioned below)

C:\Program Files (x86)\nodejs\node.exe features\steps.js\
internal/validators.js:118
    throw new ERR_INVALID_ARG_TYPE(name, 'string', value);
    ^

TypeError [ERR_INVALID_ARG_TYPE]: The "from" argument must be of type string. Received undefined
    at validateString (internal/validators.js:118:11)
    at Object.relative (path.js:437:5)
    at getDefinitionLineAndUri (c:\Projects\VisualStudioCode\CucumberAppium\node_modules\cucumber\lib\support_code_library_builder\build_helpers.js:184:27)
    at buildStepDefinitionConfig (c:\Projects\VisualStudioCode\CucumberAppium\node_modules\cucumber\lib\support_code_library_builder\build_helpers.js:124:7)
    at SupportCodeLibraryBuilder.defineStep (c:\Projects\VisualStudioCode\CucumberAppium\node_modules\cucumber\lib\support_code_library_builder\index.js:51:79)
    at Object.<anonymous> (c:\Projects\VisualStudioCode\CucumberAppium\features\steps.js:3:1)
    at Module._compile (internal/modules/cjs/loader.js:1147:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1167:10)
    at Module.load (internal/modules/cjs/loader.js:996:32)
    at Function.Module._load (internal/modules/cjs/loader.js:896:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47 {
  code: 'ERR_INVALID_ARG_TYPE',
  [Symbol(originalCallSite)]: [
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {}
  ],
  [Symbol(mutatedCallSite)]: [
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {},
    CallSite {}, CallSite {}
  ]
}

I know that there may be something that I may have overlooked.

I would be very greatful if someone could point me in the right direction.

My package.json is as follows
{
  "name": "cucumberappium",
  "version": "1.0.0",
  "main": "index.js",
  "dependencies": {
    "cucumber": "^6.0.5",
    "selenium-webdriver": "^4.0.0-alpha.7"
  },
  "devDependencies": {},
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "description": ""
}

Thanks!

Answer 1

You should be letting cucumber runner know about location of step definition files. you can find a well implemented cucumberjs project using nightwatchjs here. this might have too many details but it helps you to understand.