fix(ai): buffer streaming preamble text before code fence appears#8911
Open
temrjan wants to merge 1 commit intomarimo-team:mainfrom
Open
fix(ai): buffer streaming preamble text before code fence appears#8911temrjan wants to merge 1 commit intomarimo-team:mainfrom
temrjan wants to merge 1 commit intomarimo-team:mainfrom
Conversation
When AI models emit conversational preamble before code fences (e.g. "I'll create a cell that..."), the preamble was incorrectly created as a separate Python cell. This happened because CellCreationStream called codeToCells on partial buffer before any fence arrived, treating plain text as Python code. Now CellCreationStream buffers incoming chunks until a code fence (```) appears. Once a fence is found, codeToCells correctly extracts only the code. If the stream ends without any fence, the buffer is flushed as a cell on stop() for backward compatibility. Note: This fixes the "Generate AI cell" flow. The "Inline AI edit" flow (backend without_wrapping_backticks) is a separate issue. Fixes marimo-team#8880 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
|
The latest updates on your projects. Learn more about Vercel for GitHub.
|
|
All contributors have signed the CLA ✍️ ✅ |
Author
|
I have read the CLA Document and I hereby sign the CLA |
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
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Summary
CellCreationStreamuntil a code fence (```) appears, preventing conversational preamble from becoming a separate Python cellstop()if the stream ends without any fence (backward compatibility for models that return code without fences)Root cause
CellCreationStream.stream()calledcodeToCells(buffer)on every chunk. Before any fence arrived,codeToCellstreated the entire buffer as Python code (line 166 ofcompletion-utils.ts:if (!code.includes("```")) return [{ language: "python", code }]), creating a cell from preamble text like "I'll create a fibonacci function...".What this does NOT fix
The "Inline AI edit" flow (problem #2 in the issue) uses a different code path through the backend
without_wrapping_backticksfunction. That is a separate issue.Test plan
Fixes #8880
🤖 Generated with Claude Code