[cknitt]

Follow-up to #8958 and #8957: instead of only the page the workflow renders for each push, a viewer page draws the commit records of any pull request, range or commit in the browser, reading them from GitHub's API and drawing them with the same renderer (recordRender.js, which has no Node dependencies).

https://cdn.rescript-lang.org/semantic-diff/view/index.html?pr=8958
                                                         ?pr=8958&range=<base>...<head>
                                                         ?range=v12.0.0...v12.1.0
                                                         ?commit=<sha>[,<sha>]

• scripts/recordViewer.js maps the query to API calls (/pulls/N, /pulls/N/commits, /compare/a...b, /commits/sha), leaves out merge commits like rev-list --no-merges, and draws pageBody into the page; scripts/recordViewer.html is the page.
• Unauthenticated, GitHub allows 60 requests an hour per address. A pull request takes 2 requests (+1 per 100 commits). The viewer refuses a pull request or range of more than 250 commits (GitHub's own cap for a pull request's commits) and more than 20 named commits, so a page takes at most 4 requests, or 20 for named commits. Running out of requests shows when the limit resets.
• Range ends must be words joined by single . or / (shas, tags, branches), so a query can't point the request at another API path. Commit messages are drawn through the renderer's escaping, as on the existing pages.
• .github/workflows/semantic_diff_viewer.yml publishes the viewer to semantic-diff/view/ on a push to master. A pull request from a branch of this repository that changes the viewer or the renderer publishes its own copy under semantic-diff/view/pr-<N>/ and comments the address, so this PR can be tried before it lands. Files are served with Cache-Control: max-age=300.
• Dates are the author date in UTC (the page from git uses the author's time zone, so a commit near midnight may show a neighbouring day).

The existing per-push pages and Markdown comments are unchanged. A possible next step: link each comment to ?pr=N&range=<base>...<head>, which redraws exactly that push even after later pushes.

New tests: scripts/recordViewer.test.js (query to API calls against a fake API, pagination, limits, malformed queries), added to yarn test-commit-records.

🤖 Generated with Claude Code

https://claude.ai/code/session_01AzPS5F8RDSGZ6dhfK6NdZp

[github-actions]

Semantic Diff viewer of this pull request: https://cdn.rescript-lang.org/semantic-diff/view/pr-8962/index.html?pr=8962

[github-actions]

Semantic Diff

1 commit · Full page

Draw any pull request's records in the browser

_{8fd1816 · Christoph Knittel with Claude Opus 5.5 · Oct 22, 2026}

A Semantic Diff page exists only for a pull request the workflow rendered, and shows its latest push. The viewer reads a pull request's, a range's or commits' records from GitHub's API and draws them with the page's renderer, at most 250 commits; a workflow publishes it to the CDN from master, and from a pull request that changes it under its own address.

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commit: 8fd1816

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Developer playground preview: https://rescript-lang.github.io/rescript/dev-playground/?version=pr-8962