fix(theme-common): docs breadcrumbs not working with baseUrl

[slorber]

Motivation

fix bug reported here: #6749 (comment)

Have you read the Contributing Guidelines on pull requests?

yes

Test Plan

unit tests

[netlify]

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[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟠 Performance	65
🟢 Accessibility	100
🟢 Best practices	92
🟢 SEO	100
🟢 PWA	90

Lighthouse ran on https://deploy-preview-6816--docusaurus-2.netlify.app/

[github-actions]

Size Change: +74 B (0%)

Total Size: 789 kB

Filename	Size	Change
website/build/assets/js/main.********.js	597 kB	+74 B (0%)

ℹ️ View Unchanged

Filename	Size
website/.docusaurus/globalData.json	49.7 kB
website/build/assets/css/styles.********.css	105 kB
website/build/index.html	38.3 kB

_{compressed-size-action}

[pranabdas]

@slorber So the home icon in breadcrumbs is not supposed to show up for docs-only sites? The breadcrumb looks bit empty in this case if there is only one item. Is it possible to have home icon in this case linking to logo.href? Thank you.

[slorber]

yes it's showing for docs-only sites if there's a doc with slug: /

For breadcrumbs improvements, I suggest giving your opinion here: #6786

I don't know if logo.href is such a good fallback.

Maybe it would be better to always ensure/force that a docs site has a home 🤷‍♂️

At least you could provide a redirect from / to /something for example

[pranabdas]

Maybe there is a bug then, the home icon is not showing up in the breadcrumb in docs-only mode. Steps to reproduce:

1. Create a new site: npx create-docusaurus@latest website classic
2. cd website
3. Update to latest canary: npm i --save-exact @docusaurus/core@canary @docusaurus/preset-classic@canary
4. Remove index page rm src/pages/index.js
5. Add routeBasePath for docs in docusaurus.config.js:

module.exports = {
  // ...
  presets: [
    '@docusaurus/preset-classic',
    {
      docs: {
        routeBasePath: '/', 
      },
    },
  ],
};

6. Add slug to docs/intro.md:

slug: /

7. npm start and this is what I see:

[Josh-Cena]

Indeed, it's because the version route that the doc plugin doesn't specify exact: true or false so it isn't recognized as a home parent route... @slorber Is it intended to only match exact === false instead of !exact?

[slorber]

hmmm weird, I tested this locally and it worked 😅

Will fix this asap

[slorber]

#6824