Re: [PATCH 1/6] SubmittingPatches: clarify expected structure of commit log message
From: Junio C Hamano <hidden>
Date: 2026-07-13 00:07:06
Michael Montalbo [off-list ref] writes:
I think collapsing the "Formatting and Style Guidelines" section with the above would be clearer than having a separate section.
Thanks for pointing it out; I tend to agree. Before rerolling the series in entirety, here is what I have in my editor buffer right now, after attempting to move the formatting and styles into the main description. I haven't checked if the formatting works as AsciiDoc yet, though.
--- >8 ---[[meaningful-message]]
==== Structure of a Commit Message
1. Title:
The first line of the commit log message is the title that lets
readers of `git log --oneline` quickly understand what area the
commit touches and what problem it addresses.
- Keep it short (50 characters is the soft limit).
- Skip the full stop at the end.
- Prefix the subject with the modified area followed by a colon
and a space (e.g., "area: subject"). The area is typically a
filename or identifier (e.g., `doc:`, `transport:`, `t5601:`).
Run `git log --no-merges` on target files to see conventions.
- Do not capitalize the first word after the "area:" prefix
unless there is a specific reason (e.g., `HEAD` is always in
uppercase). For example, use "doc: clarify...", not "doc:
Clarify...".
2. Body:
A well-structured commit message body typically follows a
three-part flow: Observation, Solution Design, and
Implementation.
- Leave a blank line between the title and the body.
- Wrap lines in the body of the commit log message to around 70
columns.
- The body of the log message must be self-contained. Do not
rely on external URLs (including mailing list archives) as the
sole explanation. Summarize the relevant points of external
material so that readers can understand the change with the log
message alone.
[[present-tense]]
3. Observation (The Status Quo):
Explain the problem you are solving with your change by
describing what is wrong with the current code *without* your
change.
- As this part is always about the current state by convention,
words like "currently" are unnecessary.
- Write this problem statement in the present tense (e.g., "The
code does X when given input Y", not "The code did X").
4. Solution Design (The Approach):
Explain the approach you took, justify how it solves the problem,
and describe why you chose the particular design over other
alternatives.
- Focus on describing _why_, not _how_ (e.g., "The code does X
when given input Y, but it should do Z _because_...").
- If your change only addresses a subset of a larger problem
(e.g., it handles directories but not files because ...),
explain this limitation. This helps future developers
understand the boundaries of your work and whether it can be
safely extended.
- If your change resolves design or viability concerns raised by
the community during prior review rounds, ensure the message
records the resolution, explaining why the chosen approach was
accepted over alternatives.
[[imperative-mood]]
5. Implementation (The Execution):
Finally, describe how the changes are implemented.
- Write this in the imperative mood (e.g., "Make xyzzy do frotz",
not "This patch makes xyzzy do..." or "I changed xyzzy..."), as
if you are instructing an agent to make changes to the
codebase.
- You do not have to repeat everything readers can discern from
the patch text. Highlight the key points in your
implementation.