Function truncateStartToWidth

src/utils/truncate.ts:82–101

(text: string, maxWidth: number)

 * Width-aware and grapheme-safe.
 */
export function truncateStartToWidth(text: string, maxWidth: number): string {
  if (stringWidth(text) <= maxWidth) return text
  if (maxWidth <= 1) return '…'
  const segments = [...getGraphemeSegmenter().segment(text)]
  let width = 0
  let startIdx = segments.length
  for (let i = segments.length - 1; i >= 0; i--) {
    const segWidth = stringWidth(segments[i]!.segment)
    if (width + segWidth > maxWidth - 1) break // -1 for '…'
    width += segWidth
    startIdx = i
  }
  return (
    '…' +
    segments
      .slice(startIdx)
      .map(s => s.segment)
      .join('')
  )
}

/**
 * Truncates a string to fit within a maximum display width, without appending an ellipsis.