@mui/internal-docs-infra/pipeline/parseSource/addLineGutters.js

MUI Infra - internal documentation creation tools.

// Example copied from https://github.com/wooorm/starry-night#example-adding-line-numbers

/**
 * Counts the number of lines in a HAST tree without mutating it.
 * Uses the same logic as starryNightGutter but only returns the count.
 * @param tree - The HAST tree to count lines in
 * @returns The number of lines in the tree
 */
export function countLines(tree) {
  var search = /\r?\n|\r/g;
  var index = -1;
  var start = 0;
  var startTextRemainder = '';
  var lineNumber = 0;
  while (index + 1 < tree.children.length) {
    index += 1;
    var child = tree.children[index];
    if (child.type === 'text') {
      var textStart = 0;
      var match = search.exec(child.value);
      while (match) {
        lineNumber += 1;
        start = index + 1;
        textStart = match.index + match[0].length;
        match = search.exec(child.value);
      }

      // If we matched, make sure to not drop the text after the last line ending.
      if (start === index + 1) {
        startTextRemainder = child.value.slice(textStart);
      }
    }
  }

  // Check if we have remaining content to process as a line
  if (start < tree.children.length || startTextRemainder) {
    lineNumber += 1;
  }
  return lineNumber;
}
export function starryNightGutter(tree) {
  /** @type {Array<RootContent>} */
  var replacement = [];
  var search = /\r?\n|\r/g;
  var index = -1;
  var start = 0;
  var startTextRemainder = '';
  var lineNumber = 0;
  while (index + 1 < tree.children.length) {
    index += 1;
    var child = tree.children[index];
    if (child.type === 'text') {
      var textStart = 0;
      var match = search.exec(child.value);
      while (match) {
        // Nodes in this line.
        var _line = tree.children.slice(start, index);

        // Prepend text from a partial matched earlier text.
        if (startTextRemainder) {
          _line.unshift({
            type: 'text',
            value: startTextRemainder
          });
          startTextRemainder = '';
        }

        // Append text from this text.
        if (match.index > textStart) {
          _line.push({
            type: 'text',
            value: child.value.slice(textStart, match.index)
          });
        }

        // Add a line, and the eol.
        lineNumber += 1;
        replacement.push(createLine(_line, lineNumber), {
          type: 'text',
          value: match[0]
        });
        start = index + 1;
        textStart = match.index + match[0].length;
        match = search.exec(child.value);
      }

      // If we matched, make sure to not drop the text after the last line ending.
      if (start === index + 1) {
        startTextRemainder = child.value.slice(textStart);
      }
    }
  }
  var line = tree.children.slice(start);
  // Prepend text from a partial matched earlier text.
  if (startTextRemainder) {
    line.unshift({
      type: 'text',
      value: startTextRemainder
    });
    startTextRemainder = '';
  }
  if (line.length > 0) {
    lineNumber += 1;
    replacement.push(createLine(line, lineNumber));
  }

  // Replace children with new array.
  tree.children = replacement;

  // Add total line count to root data
  if (!tree.data) {
    tree.data = {};
  }
  tree.data.totalLines = lineNumber;
}
function createLine(children, line) {
  return {
    type: 'element',
    tagName: 'span',
    properties: {
      className: 'line',
      dataLineNumber: line
    },
    children: children
  };
}