NO_COLOR and accessibility

flagstaff decides nothing about the terminal itself. Two questions — may I redraw, and may I colour — are answered by roundel's output policy, the one every package in the family asks. Its rules are in policy.ts and pinned by policy.test.ts.

Redraws: CLI_ACCESSIBLECopy Anchor Link

A screen reader reads a redraw as a stream of fragments. Set CLI_ACCESSIBLE=1 and the policy chooses the accessible mode ahead of the terminal check: every component hoisted with hoist() prints its static projection once per state and never redraws — on a terminal as well as off one. A box is its title and text, a table is header: value lines, a progress bar is 12/30 files · 40%.

… building
… linking
✔ built

--json still wins over it: a program asked for structured output gets structured output. An empty CLI_ACCESSIBLE= counts as unset, the way NO_COLOR does.

The drop-ins are the exception, on purpose: they behave as their incumbents do. flagstaff/ora imports roundel's chalk and never the policy, because a façade that reinterpreted its host would fail the host's own suite — so on a terminal CLI_ACCESSIBLE=1 does not stop it animating, where CI=true does, because that is ora's own rule. hoist() is what honours the switch.

Colour: NO_COLOR winsCopy Anchor Link

flagstaff paints its glyphs through roundel's tokens, and a token is plain text until the program calls fly() from roundel/theme to decide a colour level. Once it has, the level is, first match wins:

1. none under --json, when NO_COLOR is set to anything but empty, or in accessible mode unless colour was asked for;
2. what was asked, when FORCE_COLOR, --color or --no-color asked — the level named, or the terminal's own level and never less than basic colour when none was named;
3. none in a pipe nobody asked to colour;
4. the terminal's own, from TERM and COLORTERM, or a known CI runner's.

The full order, edge cases included (TERM=dumb, Azure Pipelines), is colorLevel in the same file.

So NO_COLOR beats an explicit --color:

import { hoist } from 'flagstaff/loop';
import { spinner } from 'flagstaff/spinner';
import { fly } from 'roundel/theme';

import { json, rt } from './rt.mjs';

fly({}, { ...rt, argv: process.argv }, { json });
hoist(spinner(), rt, { text: 'building' }, { json }).lower({ text: 'built', status: 'ok' });

… building
✔ built

Colour is never how a state is told apart: ok and fail are ✔ and ✖ before they are green and red, so the text form carries the whole meaning with colour off.

What a screen-reader user can rely onCopy Anchor Link

• No redraws with CLI_ACCESSIBLE=1, from anything hoisted on the loop.
• No cursor movement, erase or carriage return from hoist() off a terminal, in any mode (loop.test.ts).
• A text form for every component: a plugin without one is refused at registration (Plugins).
• The cursor is shown again after lower(), and after SIGINT, SIGTERM or SIGHUP.