Make transitionCell pure by injecting parseOutline#8729
Merged
Conversation
|
The latest updates on your projects. Learn more about Vercel for GitHub.
|
Contributor
There was a problem hiding this comment.
Pull request overview
This PR refactors how a cell’s outline is derived during runtime state transitions by injecting parseOutline into transitionCell, rather than having transitionCell import DOM-dependent outline parsing directly. This helps keep the cell state transition logic usable in environments that may not support DOM APIs.
Changes:
- Update
transitionCellto accept an optionalparseOutlinefunction via a newoptionsparameter. - Move outline parsing responsibility to the caller (
cells.ts) by passingparseOutlineintotransitionCell.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
frontend/src/core/cells/cells.ts |
Passes parseOutline into transitionCell when handling kernel cell messages. |
frontend/src/core/cells/cell.ts |
Adds an options parameter to transitionCell and only parses outline when provided. |
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
frontend/src/core/cells/cell.ts
Outdated
| // Derive outline from output | ||
| nextCell.outline = parseOutline(nextCell.output); | ||
| if (options?.parseOutline) { | ||
| nextCell.outline = options.parseOutline(nextCell.output); |
Comment on lines
760
to
764
| state, | ||
| cellId, | ||
| cellReducer: (cell) => { | ||
| return transitionCell(cell, message); | ||
| return transitionCell(cell, message, { parseOutline }); | ||
| }, |
Light2Dark
reviewed
Mar 17, 2026
Collaborator
There was a problem hiding this comment.
I think there's a similar issue if you import cells/session.ts. It looks like getOutline solves this with
function getOutline(html: string): Outline | null {
// Some JS runtimes (e.g. Node.js for the VSCode extension) do not
// expose DOMParser globally. In those environments parsing isn't
// possible (without a polyfill), so return just return `null`.
if (typeof DOMParser === "undefined") {
return null;
}Could we solve the root cause instead in DOMPurify (core/sanitize.ts)
if (typeof document !== "undefined") {
DOMPurify.addHook("beforeSanitizeAttributes", (node) => { ... });
DOMPurify.addHook("afterSanitizeAttributes", (node) => { ... });
}
manzt
force-pushed
the
push-rutuqpqqzuzy
branch
from
7655d74 to
0ee6ec5
Compare
manzt
force-pushed
the
push-rutuqpqqzuzy
branch
from
0ee6ec5 to
b09fb87
Compare
The marimo-lsp extension imports `transitionCell` from the frontend via `@marimo-team/frontend/unstable_internal`. Previously `cell.ts` directly imported `parseOutline` from `dom/outline.ts`, which transitively pulled in `sanitize.ts`, DOMPurify, jotai atoms, and storage utilities that all assume a browser environment. This caused `ReferenceError: document is not defined` and `window is not defined` in the marimo-lsp Node test suite. Rather than sprinkling `typeof window` guards throughout the codebase, `parseOutline` is now an optional callback on `transitionCell`. The frontend passes it in at the single call site in `cells.ts`, while marimo-lsp callers get a pure function with no browser dependencies.
manzt
force-pushed
the
push-rutuqpqqzuzy
branch
from
b09fb87 to
f2db86c
Compare
Light2Dark
previously approved these changes
Mar 19, 2026
Collaborator
There was a problem hiding this comment.
any thoughts on the comment i made @manzt ? if not, this approach seems fine :)
The marimo-lsp extension imports `transitionCell` from the frontend, which transitively pulls in `sanitize-html.ts`. The module-level `DOMPurify.addHook` calls blow up with `ReferenceError: document is not defined` in Node.js because DOMPurify touches the DOM at registration time. Rather than injecting `parseOutline` as a callback into `transitionCell` (the previous approach on this branch), this fixes the root cause by wrapping the hooks in a `typeof document !== "undefined"` guard. This matches the existing pattern in `getOutline` which already guards against missing `DOMParser`. The `transitionCell` API stays unchanged and outline parsing continues to work in the browser while gracefully returning `null` in Node.
Collaborator
Author
|
Sorry for the delay here. Your suggestion is much cleaner :) |
|
🚀 Development release published. You may be able to view the changes at https://marimo.app?v=0.21.2-dev16 |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
The marimo-lsp extension imports
transitionCellfrom the frontend via@marimo-team/frontend/unstable_internal. Previouslycell.tsdirectly importedparseOutlinefromdom/outline.ts, which transitively pulled insanitize.ts, DOMPurify, jotai atoms, and storage utilities that all assume a browser environment. This causedReferenceError: document is not definedandwindow is not definedin the marimo-lsp Node test suite.Rather than sprinkling
typeof windowguards throughout the codebase,parseOutlineis now an optional callback ontransitionCell. The frontend passes it in at the single call site incells.ts, while marimo-lsp callers get a pure function with no browser dependencies.\