Files
coder/docs
Nick Vigilante 9dcb75cd56 chore: add docs inline-HTML linter and backtick generated placeholders (#27399)
## What

Adds CI enforcement that fails when docs Markdown contains invalid
inline HTML
the docs site silently drops or mangles, and fixes the remaining
generated-doc
placeholders at their source.

This is the tooling half of the docs-HTML audit. The hand-written fixes
it
guards landed in #27298 (kept small and separate so it reviewed fast);
this PR
carries everything that touches code, CI, or generated output.

## Changes

**Linter (`scripts/docshtmlcheck`), wired into `make lint` via
`lint/docs-html`.**
Markdown-aware: parses each file with goldmark and inspects only
raw-HTML nodes,
so angle brackets in fenced code blocks, inline code, HTML comments, and
`<https://…>` / `<user@host>` autolinks are ignored. Flags swallowed
placeholders (`<region>`), void-element end tags (`</br>`), unregistered
or
incorrectly capitalized component tags (`<Image>`), and unclosed
container tags (a
`<div class="tabs">` that leaks its wrapper). The one intentional
renderer
component, `<children>`, is allowed but still balance-checked.

**Generator-source placeholder fixes (regenerated via `make gen`).**
- `codersdk/chats.go`: backtick `<server>__` in the
`ChatContextTool.Name` doc
  comment (it becomes the Swagger description, so it was swallowed in
  `reference/api/{chats,schemas}.md`).
- `codersdk/deployment.go`: backtick `<region>` in the AWS Bedrock
region flag
help (swallowed in `reference/cli/server.md`); also updates `coder
server
  --help` output and the golden files.

**Temporary allowlist.** `docs/reference/cli/agent-firewall.md`'s
`<host>` /
`<glob>` come from the external `github.com/coder/boundary` CLI help
(still
`v0.10.0` on `main`), so they are suppressed on that one file. The
suppression
is self-clearing: if an allowlisted tag stops appearing on a scanned
file, the
linter reports `stale-allowlist-entry` and fails until the dead entry is
removed, so a dead entry cannot silently mask a later regression of that
tag on
that page. (An entry whose file is deleted outright is never rescanned,
but a
missing file yields no findings, so nothing hides behind it either.)

## Review feedback addressed

This tool + generator work was reviewed by Coder Agents Review while it
was
bundled into #27298. Addressed here:

- **P1:** tokenize each raw-HTML node as a whole instead of per source
line, so
a tag whose attributes wrap across lines is no longer torn in half. This
fixes
both the missed multi-line unclosed `<div>` (a leaked wrapper that
passed with
exit 0) and the spurious `stray-end-tag` on valid multi-line tags. Each
token
  maps back to its own source line.
- Normalize allowlist lookup/report paths to a canonical repo-relative
form, so
the escape hatch no longer silently misses under absolute / `./` paths.
- Route generated-page findings to the generator source.
- Add `<search>` to the allowed set; reword the unknown-element message
to note
  that a real element can be added to `allowedElements`.
- Self-clearing allowlist guard (above); rename `optionalEndTag(s)` and
`kindUnclosed(Tag)`; adopt `slices`/`maps` idioms; move the lint banner
to the
  Makefile recipe; stop aliasing the input slice in `filterAllowed`.
- New tests: multi-line tokenization (both classes), interleaved
nesting, a
  pinned line number, `collectMarkdown`, and the stale-allowlist guard.

### Round 2 (Coder Agents Review on this PR)

A second `/coder-agents-review` pass on this PR raised 16 findings;
addressed in
`fix(docshtmlcheck): catch self-closing containers and capitalized
tags`:

- **P2:** self-closing container tags (`<div class="tabs"/>`) were
ignored by
the HTML5 parser and leaked their wrapper like the open spelling; the
balance
  check now tracks self-closing tokens too (CRF-1).
- **P2:** a capitalized component tag whose lowercase name is a real
element
(`<Table>`, `<Section>`) slipped through on the `allowedElements`
lookup. The
tokenizer lowercases tag names, so the check now reads the raw token and
  reports any capitalized name as a component reference (CRF-2).
- Narrowed the `:` / `@` autolink skip to a real URI scheme or a dotted
`local@domain`, so `<region:id>` and `<user@host>` stay checked (CRF-3).
- Stale-allowlist findings now report against the linter source with no
line,
and count separately from invalid-HTML issues in the footer (CRF-7,
CRF-11).
- Comment / README / Makefile wording synced to the honest
capitalized-tag
  behavior; added the deleted-file allowlist caveat and a note that
`allowedElements` is hand-maintained against the renderer (CRF-14,
CRF-17,
  CRF-9).
- Internal cleanups (`pop` -> `matchEndTag`, extracted
`unclosedFinding`) and
new tests: self-closing, capitalized open/close, colon/at placeholders,
a
non-first-token line assertion, `isGeneratedDoc`, and the stale message
  (CRF-12, CRF-13, CRF-1/2/3/4/5/16).

Two findings resolved without a code change:

- **CRF-8** (also wire `lint/docs-html` into `lint-light`): declined.
  `lint-light` is the Go-free fast path; `lint/docs-html` needs the Go
toolchain, so it stays in the full `make lint`, which CI runs. Adding it
would
  pull Go into the light path for no coverage gain.
- **CRF-9** (`allowedElements` <-> renderer coupling): documented with a
maintenance note in the `allowedElements` comment and tracked in
DOCS-597 for
  a cross-repo sync/check decision.

Deferred (note, no current trigger): raw-text element interiors
(`<script>` / `<style>`) are not scanned for nested tags. No docs page
relies
on this today; noted for follow-up.

## Merge order

#27298 (the hand-written fixes this PR guards) has merged, and this
branch is
rebased on `main`, so `make lint/docs-html` now reports 0 findings and
the
`lint` check passes. The two PRs are independent (disjoint files, no
stacking).

## Verification

- `go test ./scripts/docshtmlcheck/`, `go vet`, `gofmt -l`,
`golangci-lint run`: clean.
- `make lint/docs-html` (branch rebased on `main`): 0 findings.

## Linear

- DOCS-584:
https://linear.app/codercom/issue/DOCS-584/add-ci-check-that-fails-on-invalid-inline-html-in-docs
- DOCS-551:
https://linear.app/codercom/issue/DOCS-551/backtick-placeholder-syntax-in-generated-reference-docs-cli-help
- DOCS-597 (follow-up, from CRF-9):
https://linear.app/codercom/issue/DOCS-597/track-docshtmlcheck-allowedelements-drift-vs-docs-renderer-component

> This PR was created with AI assistance (Coder Agents).
2026-08-05 14:45:45 -04:00
..

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