Function moveCursorTo

src/ink/log-update.ts:693–721

(screen: VirtualScreen, targetX: number, targetY: number)

}

function moveCursorTo(screen: VirtualScreen, targetX: number, targetY: number) {
  screen.txn(prev => {
    const dx = targetX - prev.x
    const dy = targetY - prev.y
    const inPendingWrap = prev.x >= screen.viewportWidth

    // If we're in pending wrap state (cursor.x >= width), use CR
    // to reset to column 0 on the current line without advancing
    // to the next line, then issue the cursor movement.
    if (inPendingWrap) {
      return [
        [CARRIAGE_RETURN, { type: 'cursorMove', x: targetX, y: dy }],
        { dx, dy },
      ]
    }

    // When moving to a different line, use carriage return (\r) to reset to
    // column 0 first, then cursor move.
    if (dy !== 0) {
      return [
        [CARRIAGE_RETURN, { type: 'cursorMove', x: targetX, y: dy }],
        { dx, dy },
      ]
    }

    // Standard same-line cursor move
    return [[{ type: 'cursorMove', x: dx, y: dy }], { dx, dy }]
  })
}

/**
 * Identify emoji where the terminal's wcwidth may disagree with Unicode.