remark-mdx esm nodes not being detected

Initial checklist

• I read the support docs
• I read the contributing guide
• I agree to follow the code of conduct
• I searched issues and couldn’t find anything (or linked relevant results below)

Affected packages and versions

latest

Link to runnable example

No response

Steps to reproduce

import { remark } from "remark";
import remarkMdx from "remark-mdx";
import type { Root } from "mdast";
import { remove } from "unist-util-remove";

const removeImports = () => {
  return (tree: Root) => {
    remove(tree, (node) => {
      return (
        node.type === "mdxjsEsm" &&
        node?.value &&
        node?.value.startsWith("import")
      );
    });
    return tree;
  };
};

export const preParseMdx = async (content: string): Promise<string> => {
  const file = await remark()
    .use(remarkMdx)
    .use(removeImports)
    .process(content);
  return String(file);
};

  const content = `
  import test1 from 'test1'
  import test2 from 'test2'


  import test3 from 'test3'


  TEXT POST IMPORTS!!!!!!!!
  `;
await preParseMdx(content);

Expected behavior

Due to the custom plugin imports should be removed after running the above code. This made me suspect that the esm nodes are not being detected properly, but inside the remark-mdx package readme it says that it is.

Actual behavior

The import statements aren’t being detected and are labeled as type: "text" and not type: "mdxjsEsm"

Runtime

Node v17

Package manager

npm v8

OS

macOS

Build and bundle tools

No response

[hahnbeelee]

@wooorm Thanks for the insight Titus. This was 100% what was going on.

[ChristianMurphy]

Strange indeed. https://mdxjs.com/community/support/ offers some ideas. In particular creating a sandbox with a runnable example of the issue you are seeing may help folks offer more concrete suggestions.