cedit — continuous editing of vendored Markdown

• Repository: github.com/sdlctools/cedit
• Package: pypi.org/project/cedit
• Docs: sdlctools.github.io/cedit

Why it exists

Say you cloned this plugin and adapted it: different branch names, extra logic on a state move, a fence rewritten because your environment runs zsh rather than bash. You now want both things at once — your edits in place, and upstream's fixes as they land. A git merge of a vendored copy gives you line-level conflicts across a document that was reflowed; re-applying your changes by hand after every update gives you drift.

cedit keeps a persistent block-level overlay of your adaptations and re-applies it by 3-way structural merge on the document's AST. Your edits survive upstream reflows and moved blocks, upstream changes to blocks you never touched flow straight in, and you are told — per block, with all three versions — when upstream edited the very thing you had adapted.

How it works

Each document is parsed into an AST and Merkle-hashed per block, so the merge keys on blocks, not lines. Three versions meet at each block (base, upstream, local) and the merge matrix decides: reuse yours, take theirs, or raise a conflict. State lives in a committed .cedit/ folder — the base snapshots are the merge's memory.

pipx install cedit

cedit snapshot skills/SKILL.md --from vendor/skills/SKILL.md   # start tracking
# …adapt the file in place…
cedit diff                       # what your overlay currently holds
cedit sync --from vendor         # upstream moved: re-apply the overlay over it
cedit resolve skills/SKILL.md <hash> --take local   # or --take upstream
cedit status

Exit codes are 0 clean, 1 unresolved conflicts, 2 error. A document with open conflicts refuses to sync again, and the working file always keeps your text until you resolve it — never a silent clobber.

A second, stateless command group exposes the parser itself — cedit md canonicalize, blocks, ast, json — a file in, stdout out, no state touched. This repository uses that group: the markdown-canonicalize workflow runs cedit md canonicalize --check over every changed .md, which is also why AGENTS.md tells you to canonicalize before pushing.

Status

Alpha, and phase 1 of its spec: it merges replacements — prose, fences, table cells, front matter — and rejects local structural edits (inserting, deleting or moving whole blocks) with a per-block report rather than guessing. Fetching upstream is out of scope: --from takes a directory or a file, and git submodules, subtrees or a copy step are your transport. Pin the version if stability matters to you; nothing is promised stable before 1.0.