Function codeFrameColumns

packages/babel-code-frame/src/index.ts:126–201

(
  rawLines: string,
  loc: NodeLocation,
  opts: Options = {},
)

}

export function codeFrameColumns(
  rawLines: string,
  loc: NodeLocation,
  opts: Options = {},
): string {
  const shouldHighlight =
    opts.forceColor || (isColorSupported() && opts.highlightCode);
  const startLineBaseZero = (opts.startLine || 1) - 1;
  const defs = getDefs(shouldHighlight);

  const lines = rawLines.split(NEWLINE);
  const { start, end, markerLines } = getMarkerLines(
    loc,
    lines,
    opts,
    startLineBaseZero,
  );
  const hasColumns = loc.start && typeof loc.start.column === "number";

  const numberMaxWidth = String(end + startLineBaseZero).length;

  const highlightedLines = shouldHighlight ? highlight(rawLines) : rawLines;

  let frame = highlightedLines
    .split(NEWLINE, end)
    .slice(start, end)
    .map((line, index) => {
      const number = start + 1 + index;
      const paddedNumber = ` ${number + startLineBaseZero}`.slice(
        -numberMaxWidth,
      );
      const gutter = ` ${paddedNumber} |`;
      const hasMarker = markerLines[number];
      const lastMarkerLine = !markerLines[number + 1];
      if (hasMarker) {
        let markerLine = "";
        if (Array.isArray(hasMarker)) {
          const markerSpacing = line
            .slice(0, Math.max(hasMarker[0] - 1, 0))
            .replace(/[^\t]/g, " ");
          const numberOfMarkers = hasMarker[1] || 1;

          markerLine = [
            "\n ",
            defs.gutter(gutter.replace(/\d/g, " ")),
            " ",
            markerSpacing,
            defs.marker("^").repeat(numberOfMarkers),
          ].join("");

          if (lastMarkerLine && opts.message) {
            markerLine += " " + defs.message(opts.message);
          }
        }
        return [
          defs.marker(">"),
          defs.gutter(gutter),
          line.length > 0 ? ` ${line}` : "",