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@jsvision/core / probeAmbiguousWidth

Function: probeAmbiguousWidth() ​

probeAmbiguousWidth(query, options?): Promise<WidthProbeResult>

Defined in: host/width-probe.ts:231

Measure how many columns each probe group advances on the live terminal.

Writes CR + arrows + DSR + CR + boxes + DSR, reads both CPR replies under one bounded timeout, then erases the probe artifact. Always resolves, never rejects: a throwing write/read, a silent terminal (timeout), a single-group reply, or an oversized reply all yield probed:false with both groups unmeasured.

Parameters ​

query ​

TerminalQuery

The terminal to probe (a real TTY-backed query or a test double).

options? ​

WidthProbeOptions = {}

Per-group probe strings + shared timeout overrides.

Returns ​

Promise<WidthProbeResult>

The WidthProbeResult; probed: false if the terminal did not answer.

Example ​

ts
import { createTerminalQuery, probeAmbiguousWidth } from '@jsvision/core';

// On a real TTY in raw mode, before entering the alternate screen:
const query = createTerminalQuery();
try {
  const result = await probeAmbiguousWidth(query);
  if (result.probed && (result.arrows.wide || result.boxes.wide)) {
    console.error('terminal renders chrome glyphs double-width');
  }
} finally {
  query.close();
}