Function measureTextNode

src/ink/dom.ts:332–374

(
  node: DOMNode,
  width: number,
  widthMode: LayoutMeasureMode,
)

}

const measureTextNode = function (
  node: DOMNode,
  width: number,
  widthMode: LayoutMeasureMode,
): { width: number; height: number } {
  const rawText =
    node.nodeName === '#text' ? node.nodeValue : squashTextNodes(node)

  // Expand tabs for measurement (worst case: 8 spaces each).
  // Actual tab expansion happens in output.ts based on screen position.
  const text = expandTabs(rawText)

  const dimensions = measureText(text, width)

  // Text fits into container, no need to wrap
  if (dimensions.width <= width) {
    return dimensions
  }

  // This is happening when <Box> is shrinking child nodes and layout asks
  // if we can fit this text node in a <1px space, so we just say "no"
  if (dimensions.width >= 1 && width > 0 && width < 1) {
    return dimensions
  }

  // For text with embedded newlines (pre-wrapped content), avoid re-wrapping
  // at measurement width when layout is asking for intrinsic size (Undefined mode).
  // This prevents height inflation during min/max size checks.
  //
  // However, when layout provides an actual constraint (Exactly or AtMost mode),
  // we must respect it and measure at that width. Otherwise, if the actual
  // rendering width is smaller than the natural width, the text will wrap to
  // more lines than layout expects, causing content to be truncated.
  if (text.includes('\n') && widthMode === LayoutMeasureMode.Undefined) {
    const effectiveWidth = Math.max(width, dimensions.width)
    return measureText(text, effectiveWidth)
  }

  const textWrap = node.style?.textWrap ?? 'wrap'
  const wrappedText = wrapText(text, width, textWrap)

  return measureText(wrappedText, width)
}

// ink-raw-ansi nodes hold pre-rendered ANSI strings with known dimensions.
// No stringWidth, no wrapping, no tab expansion — the producer (e.g. ColorDiff)