es5-compliance

Original：🇺🇸 English
Translated

This skill should be used when the user asks to "write a business rule", "create a script include", "write server-side code", "fix SyntaxError", "background script", "scheduled job", "workflow script", or any ServiceNow server-side JavaScript development.

6installs
Sourcegroeimetai/snow-flow
Added on

NPX Install

npx skill4agent add groeimetai/snow-flow es5-compliance

Tags

Translated version includes tags in frontmatter
servicenow-server-scriptses5-syntax-compliancejavascript-scriptingscript-validationservicenow-development

SKILL.md Content

View Translation Comparison →

ES5 Compliance for ServiceNow

ServiceNow runs on Mozilla Rhino engine which only supports ES5 JavaScript (2009 standard). All server-side scripts MUST use ES5 syntax.

Forbidden Syntax (WILL CAUSE SyntaxError)

ES6+ SyntaxES5 Alternative
const x = 5
var x = 5
let items = []
var items = []
() => {}
function() {}
`Hello ${name}`
'Hello ' + name
for (x of arr)
for (var i = 0; i < arr.length; i++)
{a, b} = obj
var a = obj.a; var b = obj.b;
[a, b] = arr
var a = arr[0]; var b = arr[1];
...spread
Use 
Array.prototype.slice.call()
class MyClass {}
Use constructor functions
async/await
Use GlideRecord callbacks
Promise
Use GlideRecord with callbacks

Common Patterns

Variable Declarations

javascript
// WRONG - ES6
const MAX_RETRIES = 3;
let currentUser = gs.getUser();

// CORRECT - ES5
var MAX_RETRIES = 3;
var currentUser = gs.getUser();

Functions

javascript
// WRONG - Arrow functions
var active = incidents.filter(inc => inc.active);
var process = () => { return 'done'; };

// CORRECT - ES5 functions
var active = [];
for (var i = 0; i < incidents.length; i++) {
  if (incidents[i].active) {
    active.push(incidents[i]);
  }
}
var process = function() { return 'done'; };

String Concatenation

javascript
// WRONG - Template literals
var message = `Incident ${number} assigned to ${user}`;

// CORRECT - String concatenation
var message = 'Incident ' + number + ' assigned to ' + user;

Loops

javascript
// WRONG - for...of
for (var item of items) {
  gs.info(item);
}

// CORRECT - Traditional for loop
for (var i = 0; i < items.length; i++) {
  gs.info(items[i]);
}

Default Parameters

javascript
// WRONG - Default parameters
function process(incident, priority = 3) {
  // ...
}

// CORRECT - Manual defaults
function process(incident, priority) {
  if (typeof priority === 'undefined') {
    priority = 3;
  }
  // ...
}

Automatic Validation

Before deploying any server-side script:
  1. Check for 
    const
    /
    let
    declarations - convert to 
    var
  2. Check for arrow functions 
    =>
    - convert to 
    function()
  3. Check for template literals 
    `
    - convert to string concatenation
  4. Check for destructuring 
    {a, b}
    - convert to explicit property access
  5. Check for 
    for...of
    loops - convert to index-based loops

Exception: Client Scripts

Client-side scripts (Client Scripts, UI Policies) run in the browser and MAY support ES6+ depending on user's browser. However, for maximum compatibility, ES5 is still recommended.