Refactor: Improve createExcerpt in markdownUtils

[priyanshscpp]

This commit refactors the createExcerpt function in packages/docusaurus-utils/src/markdownUtils.ts.

The key changes include:

• The function now utilizes the remark and strip-markdown libraries to parse Markdown content and remove Markdown/HTML syntax. This replaces the previous regex-heavy approach for syntax stripping, leading to more robust and accurate excerpt generation.
• The existing line-by-line processing logic for identifying the first contentful line (ignoring H1 headings, import/export statements, and code blocks) has been preserved to maintain stability and backward compatibility, especially as createExcerpt is deprecated.

A comprehensive suite of unit tests has been added in packages/docusaurus-utils/src/__tests__/markdownUtils.test.ts to ensure the refactored function behaves as expected across various scenarios. These tests cover different types of content, Markdown syntax, HTML tags, and edge cases.

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• If this is a new API or substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

Motivation

Test Plan

Test links

Deploy preview: https://deploy-preview-_____--docusaurus-2.netlify.app/

Related issues/PRs

[facebook-github-bot]

Hi @priyanshscpp!

Thank you for your pull request and welcome to our community.

Action Required

In order to merge any pull request (code, docs, etc.), we require contributors to sign our Contributor License Agreement, and we don't seem to have one on file for you.

Process

In order for us to review and merge your suggested changes, please sign at https://code.facebook.com/cla. If you are contributing on behalf of someone else (eg your employer), the individual CLA may not be sufficient and your employer may need to sign the corporate CLA.

Once the CLA is signed, our tooling will perform checks and validations. Afterwards, the pull request will be tagged with CLA signed. The tagging process may take up to 1 hour after signing. Please give it that time before contacting us about it.

If you have received this in error or have any questions, please contact us at [email protected]. Thanks!

[netlify]

✅ [V2]

Built without sensitive environment variables

Name	Link
🔨 Latest commit	d3d975c
🔍 Latest deploy log	https://app.netlify.com/projects/docusaurus-2/deploys/683dbf84e2f7080008359ad2
😎 Deploy Preview	https://deploy-preview-11229--docusaurus-2.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[github-actions]

⚡️ Lighthouse report for the deploy preview of this PR

URL	Performance	Accessibility	Best Practices	SEO	Report
/	🟠 83	🟢 98	🟢 100	🟢 100	Report
/docs/installation	🟠 50	🟢 97	🟢 100	🟢 100	Report
/docs/category/getting-started	🟠 71	🟢 100	🟢 100	🟠 86	Report
/blog	🟠 61	🟢 96	🟢 100	🟠 86	Report
/blog/preparing-your-site-for-docusaurus-v3	🔴 46	🟢 92	🟢 100	🟢 100	Report
/blog/tags/release	🟠 62	🟢 96	🟢 100	🟠 86	Report
/blog/tags	🟠 73	🟢 100	🟢 100	🟠 86	Report

[facebook-github-bot]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Meta Open Source project. Thanks!