shelving/util/ansimodule

Constants and a helper for wrapping terminal output in ANSI escape codes. Use these when writing CLI tools or test reporters that need colour and style without pulling in a third-party library.

• All colour/style constants are plain escape-code strings, so you can concatenate them yourself or pass them to ansiWrap().
• ansiWrap emits colour only when the runtime supports it, resolved once at module load the way the broader CLI ecosystem does — precedence FORCE_COLOR > NO_COLOR > TTY detection > default-off. Colour is emitted only when the output is an interactive TTY (or FORCE_COLOR opts in), so non-interactive sinks (files, log aggregators, serverless platforms like Cloudflare Workers) get plain text by default.
• NO_COLOR (any non-empty value) forces colour off, per no-color.org; FORCE_COLOR forces it on (0/false forces off) and overrides NO_COLOR.

Usage

Wrapping text in colour or style

import { ansiWrap, ANSI_RED, ANSI_BOLD } from "shelving/util";

console.log(ansiWrap("Error!", ANSI_RED));
console.log(ansiWrap("Warning", ANSI_YELLOW, ANSI_BOLD)); // multiple wrappers

Pre-coloured status icons

import { ANSI_SUCCESS, ANSI_FAILURE, ANSI_WAITING } from "shelving/util";

console.log(ANSI_SUCCESS); // ✓ in green
console.log(ANSI_FAILURE); // ✗ in red
console.log(ANSI_WAITING); // ⋯ in blue

Arrow icons (ANSI_UP, ANSI_DOWN, ANSI_LEFT, ANSI_RIGHT) are also available in blue.

Each icon is a plain string constant resolved once at module load via ansiWrap(), so colour is detected at import time — a TTY yields the coloured glyph, a non-interactive sink (file, log aggregator, Cloudflare Worker) yields the bare glyph.

Using raw escape constants

import { ANSI_CYAN, ANSI_UNDERLINE, ANSI_RESET } from "shelving/util";

const styled = `${ANSI_CYAN}${ANSI_UNDERLINE}link text${ANSI_RESET}`;