Setting the current version's path to / freezes docsVersionDropdown

[DillonMic]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Prerequisites

• I'm using the latest version of Docusaurus.
• I have tried the npm run clear or yarn clear command.
• I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• I have tried creating a repro with https://new.docusaurus.io.
• I have read the console error message carefully (if applicable).

Description

When creating a Docusaurus site with versioning enabled, setting the current version's path to / freezes the dynamic docsVersionDropdown nav bar item. The website still works fine and successfully changes the displayed version, but the dropdown loses it's ability to correctly display which version is being rendered.

Reproducible demo

https://stackblitz.com/edit/github-lptjtc?file=docusaurus.config.js

Steps to reproduce

These steps have already been conducted on the playground link above

1. Create some versions of the documentation site

npm run docusaurus docs:version v0.1.2
npm run docusaurus docs:version v0.2.0

2. Add versions to docusaurus.config.js, and set the current version's path to /

const config = {
  presets: [
    [
      'classic',
      /** @type {import('@docusaurus/preset-classic').Options} */
      ({
        docs: {
          versions: {
            current: {
              label: 'Current',
              path: '/',
            },
            'v0.1.2': {
              label: 'v0.1.2',
              path: 'v0.1.2',
            },
            'v0.2.0': {
              label: 'v0.2.0',
              path: 'v0.2.0',
            },
          },

3. Add the docsVersionDropdown to the nav bar

export default {
  themeConfig: {
    navbar: {
      items: [
        {
          type: 'docsVersionDropdown',
        },
      ],
    },
  },
};

4. Observe the dropdown menu does not dynamically display which version is being rendered

Expected behavior

Expected behavior should be that the version dropdown displays the label of the version that is being rendered on the page. This successfully happens when the path is changed to anything but /.

Actual behavior

The version dropdown stays stuck on the Current version. It will still successfully change which version of documentation is rendered on the site, but does not change the appearance of the dropdown.

Your environment

• Public source code: https://stackblitz.com/edit/github-lptjtc?file=docusaurus.config.js
• Public site URL: https://stackblitz.com/edit/github-lptjtc?file=docusaurus.config.js
• Docusaurus version used: 3.4.0
• Environment name and version (e.g. Chrome 89, Node.js 16.4): Chrome Version 125.0.6422.142 (Official Build) (arm64)
• Operating system and version (e.g. Ubuntu 20.04.2 LTS): macOS Sonoma Version 14.5 (23F79)

Self-service

• I'd be willing to fix this bug myself.

[OzakIOne]

I have some error in your sandbox however I reproduced it here and confirm the bug happens when path: '/', but doesn't if path: '/aze',

[slorber]

Hmmm I see the problem is that we rely on the fact that the version is the "last one" to do the matching, but instead we should rather rely on the path.

This may not be the solution you look for, but this fixes the problem:

lastVersion: 'current',

The problematic code is likely this:

export function getActiveVersion(
  data: GlobalPluginData,
  pathname: string,
): GlobalVersion | undefined {
  const lastVersion = getLatestVersion(data);
  // Last version is a route like /docs/*,
  // we need to match it last or it would match /docs/version-1.0/* as well
  const orderedVersionsMetadata = [
    ...data.versions.filter((version) => version !== lastVersion),
    lastVersion,
  ];
  return orderedVersionsMetadata.find(
    (version) =>
      !!matchPath(pathname, {
        path: version.path,
        exact: false,
        strict: false,
      }),
  );
} 

Instead we should replace by code which matches the version with path '/' last (which is usually, but not always, the last version)

@OzakIOne can you look at fixing this?

[DillonMic]

That solution worked for me. Thanks @slorber !