Git-parity: -N commit-count shorthand + single-<ref> range semantics (format-patch, log, rev-list)

Git-parity: -N commit-count shorthand + single-<ref> range semantics (format-patch, log, rev-list)

Summary

Two git muscle-memory gaps surfaced while using muse format-patch. Agents and devs coming from git reach for these idioms reflexively; muse should accept them (or diverge only with a loud, documented reason). Both are low-severity (workable) but high collision-likelihood.

1. -N commit-count shorthand is not accepted

git format-patch -1 / -N exports the last N commits from HEAD. muse format-patch -1 fails:

❌ '-1' is not a known branch or commit ID.

The -N shorthand is a pervasive git idiom (git log -3, git format-patch -1, …). muse log supports -n/--max-count N but not the bare -N form. Agents will reach for -N first.

2. Single-<ref> range semantics diverge from git (silent footgun)

git format-patch <ref> exports <ref>..HEAD — commits since <ref> (exclusive). muse format-patch <ref> instead exports the single commit AT <ref> (its parent → ref). A git user who passes the base ref expecting "everything since the base" silently gets the wrong patch, with no error:

# branch tip = a6ca2233, its parent = e452ad9a
muse format-patch e452ad9a   # exported e452ad9a ITSELF (wrong) — expected a6ca2233
muse format-patch a6ca2233   # had to pass the commit itself to export it

This bit a real workflow during the rc13 ship-out (exporting a6ca2233 to park it as a mist): the first attempt passed the parent and produced the wrong .mpatch, caught only by inspecting to_commit_id.

Proposed

• Accept -N (last N commits) on format-patch, and audit log / rev-list for the same bare--N git shorthand.
• Either align format-patch <ref> to git's <ref>..HEAD semantics, or keep single-commit semantics but require an explicit A..B range for "since" and document the divergence prominently in --help and the gitism glossary.
• Sweep other ref/range-taking commands (log, rev-list, diff, range-diff) for the same two gaps and capture them here or in linked tickets.

Context

Surfaced during the rc13 ship-out. Worked around at the time; filed so the git-parity gaps are captured where agents will reach for them.