roojs-coding-standards

name	roojs-coding-standards
description	Enforces Roo.js JavaScript coding standards for this project. Use when implementing, editing, or reviewing Roo.js code, Roo.bootstrap components, Roo.extend classes, XComponent modules, or any JavaScript in this repository.

Roo.js Coding Standards

Mandatory for all Roo.js implementation work in this repository.

Before writing or changing code

1. Read docs/coding-standards.md — canonical, full standards.
2. If building or changing components, also read docs/building-components.md.
3. Match surrounding code in the file you are editing; when in doubt, follow the docs above.

Do not rely on general JavaScript style or other projects' conventions. This project's Roo.js rules override them.

Critical rules (never violate)

These are called out in the doc as CRITICAL or FORBIDDEN:

Rule	Requirement
Underscore prefix	No new _name variables or properties (except established framework names like _tree, _strings)
Shared mutable defaults	Never [] or {} on the Roo.extend prototype — use false and lazy init
String building in loops	No s += "x" in loops — use Array(n).join or array + join
Character looping	No char-by-char string loops — use indexOf, split, replace, regex
Template literals	Use + concatenation unless the user explicitly asks for backticks
Unset values	Use false, not null, for optional Roo state

High-priority patterns

Apply these on every change (details and examples in the doc):

• JSDoc: Multiline /** ... */ with @class, @cfg, @param, @return, @event as appropriate — not one-liners for behaviour.
• Braces: Constructor function(config) { same line; prototype methods in Roo.extend put { on the next line; control structures if (x) { same line, never one-line if.
• this.: Always prefix instance properties and methods inside component methods.
• Temp variables: Inline single-use and trivial aliases; alias only 4+ step chains.
• Nesting: Early return / continue; flat loop bodies; prefer switch over long if/else if chains.
• Defaults: Scalar defaults on prototype in Roo.extend; per-instance collections in constructor or lazy init.
• Methods: Prefer extending onRender, getAutoCreate, etc.; no new helpers unless the task requires them.
• Debug: Roo.debug && Roo.log(...) — no class/method names or timestamps in messages.
• Structure: Roo.namespace → constructor → Roo.extend → lifecycle overrides only when needed.

Terminology

• Element — thin DOM wrapper (Roo.Element, Roo.bootstrap.Element).
• Component — widget extending Roo.Component / Roo.bootstrap.Component.

Verification checklist

Before finishing a Roo.js change:

• Read relevant sections of docs/coding-standards.md for the areas touched
• No new underscore-prefixed names
• No []/{} prototype defaults; false for unset optional state
• Brace style matches Roo.extend vs constructor rules
• JSDoc updated for new/changed public API
• No template literals unless requested
• Minimal scope — no extra helpers or unrelated refactors

Additional resources

• docs/coding-standards.md — full standards with good/bad examples
• docs/building-components.md — component hierarchy, skeleton, lifecycle