indentedCodeBlock.js

const visit = require('unist-util-visit');

const indentedCodeBlock = () => (tree) => {
  visit(
    tree,
    (node) => node.type === 'code',
    (codeBlock, index, parent) => {
      const values = codeBlock.value.split('```').filter(Boolean);
      for (const value of values) {
        const index = values.indexOf(value);
        if (index === 0) {
          codeBlock.value = value;
          continue;
        }
        parent.children.splice(index + 1, 0, {
          type: i % 2 !== 0 ? 'text', 'code',
            value,
        });
      };
    }
  );
};

module.exports = indentedCodeBlock;