how tdo you test js files in vscode code example

Example 1: vs code enable "html" in "javascript"

"emmet.includeLanguages": {
    "javascript": "javascriptreact",
    "vue-html": "html",
    "razor": "html",
    "plaintext": "pug"
}

Example 2: how to run js file in vs code

Simply open the .js file in question in VS Code, 
  switch to the 'Debug Console' tab, hit the debug button 
  in the left nav bar, and click the run icon (play button)!