Commit Graph

12 Commits

Author SHA1 Message Date
Junio C Hamano
77f8d994a8 Merge branch 'kh/doc-committer-date-is-author-date'
The "--committer-date-is-author-date" option of "git am/rebase" is
a misguided one.  The documentation is updated to discourage its
use.

* kh/doc-committer-date-is-author-date:
  doc: warn against --committer-date-is-author-date
2025-12-05 14:49:57 +09:00
Kristoffer Haugsbakk
fbf3d0669f doc: warn against --committer-date-is-author-date
This option could create a commit history which violates the assumption
that commits have non-decreasing commit timestamps. Warn against that in
both git-am(1) and git-rebase(1).

The genesis of this option is from git-am(1) and was added in
3f01ad66 (am: Add --committer-date-is-author-date option,
2009-01-22). The commit message doesn’t give us an example
of a use case, but the thread starter does:[1]

    I've a big set of patches in a mbox file: there's sufficient info
    inside for git-am to work.

    Yet, each time I do import these, my sha1sums are changing because of
    different commit dates.

    I'd like to force the commit date to match the info/date from the time
    I received the email (and therefore always get back the right
    sha1sums).

[1]: https://lore.kernel.org/git/46d6db660901221441q60eb90bdge601a7a250c3a247@mail.gmail.com/

So the motivation was to treat git-am(1) as an import command that
creates the same commit IDs.

Putting aside the question of whether you should be using git-am(1) for
importing commits, this approach is problematic:

• you still need to apply the commits to the same base if you want the
  same hashes; and
• you need the same committer.

And if you expect the same committer, why is this person applying the
same patches multiple times with the goal of making *identical* commits?

That was all for git-am(1).

It was added to git-rebase(1) in 570ccad3 (rebase: add options passed to
git-am, 2009-03-18)[2] in order to plug options that could not be sent
on to git-am(1). At this point the utility of the option graduated to
making no sense; a use case for `git rebase --committer-date-is-author-
date` is still yet to be found.

Just warn against using this option on both commands and remind the user
to consider whether they really need it.

† 2: See also 7573cec5 (rebase -i: support
     --committer-date-is-author-date, 2020-08-17) for the commit for the
     merge backend

Suggested-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-11-20 10:03:31 -08:00
Junio C Hamano
e345b776f6 Merge branch 'je/doc-rebase'
Documentation for "git rebase" has been updated.

* je/doc-rebase:
  doc: git-rebase: update discussion of internals
  doc: git-rebase: move --onto explanation down
  doc: git rebase: clarify arguments syntax
  doc: git rebase: dedup merge conflict discussion
  doc: git-rebase: start with an example
2025-08-28 11:28:57 -07:00
Julia Evans
3f7f2b0359 doc: git-rebase: update discussion of internals
- make it clearer that we're talking about a multistep process
- give a more technically accurate description how rebase works with the
  merge backend.
- condense the explanation of how git rebase skips commits with the same
  textual changes into a single bullet point and remove the explanatory
  diagram. Lots of things which are more complicated are already being
  explained without a diagram.
- remove the explanation of how exactly `--fork-point` and `--root`
  work since that information is in the OPTIONS section
- put all discussion of `ORIG_HEAD` inside the note

Signed-off-by: Julia Evans <julia@jvns.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-23 09:03:30 -07:00
Julia Evans
981ce57389 doc: git-rebase: move --onto explanation down
There's a very clear explanation with examples of using --onto which is
currently buried in the very long DESCRIPTION section. This moves it to
its own section, so that we can reference the explanation from the
`--onto` option by name.

Signed-off-by: Julia Evans <julia@jvns.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-23 09:03:29 -07:00
Julia Evans
1469715a9c doc: git rebase: clarify arguments syntax
Remove duplicate explanation of `git rebase <upstream> <branch>` which
is already explained above.

Signed-off-by: Julia Evans <julia@jvns.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-23 09:03:29 -07:00
Julia Evans
af5a099197 doc: git rebase: dedup merge conflict discussion
Previously there were two explanations, this combines them both into a
single explanation.

Signed-off-by: Julia Evans <julia@jvns.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-23 09:03:29 -07:00
Julia Evans
f39a29c22e doc: git-rebase: start with an example
- Start with an example that mirrors the example in the `git-merge` man
  page, to make it easier for folks to understand the difference between
  a rebase and a merge.
- Mention that rebase can combine or reorder commits

Signed-off-by: Julia Evans <julia@jvns.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-23 09:03:28 -07:00
Jean-Noël Avila
63d33eb7f6 doc: check well-formedness of delimited sections
Having an empty line before each delimited sections is not required by
asciidoc, but it is a safety measure that prevents generating malformed
asciidoc when generating translated documentation.

When a delimited section appears just after a paragraph, the asciidoc
processor checks that the length of the delimited section header is
different from the length of the paragraph. If it is not, the asciidoc
processor will generate a title. In the original English documentation, this
is not a problem because the authors always check the output of the asciidoc
processor and fix the length of the delimited section header if it turns out
to be the same as the paragraph length. However, this is not the case for
translations, where the authors have no way to check the length of the
delimited section header or the output of the asciidoc processor. This can
lead to a section title that is not intended.

Indeed, this test also checks that titles are correctly formed, that is,
the length of the underline is equal to the length of the title (otherwise
it would not be a title but a section header).

Finally, this test checks that the delimited section are terminated within
the same file.

Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-11 14:16:03 -07:00
Jean-Noël Avila
227c4f33a0 doc: add a blank line around block delimiters
The documentation is using the historical mode for titles, which is a
setext-style (i.e., two-line) section title.

The issue with this mode is that starting block delimiters (e.g.,
`----`) can be confused with a section title when they are exactly the
same length as the preceding line. In the original documentation, this
is taken care of for English by the writer, but it is not the case for
translations where these delimiters are hidden. A translator can
generate a line that is exactly the same length as the following block
delimiter, which leads to this line being considered as a title.

To safeguard against this issue, add a blank line before and after
block delimiters where block is at root level, else add a "+" line
before block delimiters to link it to the preceding paragraph.

Signed-off-by: Jean-Noël Avila <jn.avila@free.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-03-10 09:58:06 -07:00
Junio C Hamano
37b34c4e99 Merge branch 'mh/doc-commit-title-not-subject'
The documentation of "git commit" and "git rebase" now refer to
commit titles as such, not "subject".

* mh/doc-commit-title-not-subject:
  doc: use 'title' consistently
2025-02-25 14:19:36 -08:00
brian m. carlson
1f010d6bdf doc: use .adoc extension for AsciiDoc files
We presently use the ".txt" extension for our AsciiDoc files.  While not
wrong, most editors do not associate this extension with AsciiDoc,
meaning that contributors don't get automatic editor functionality that
could be useful, such as syntax highlighting and prose linting.

It is much more common to use the ".adoc" extension for AsciiDoc files,
since this helps editors automatically detect files and also allows
various forges to provide rich (HTML-like) rendering.  Let's do that
here, renaming all of the files and updating the includes where
relevant.  Adjust the various build scripts and makefiles to use the new
extension as well.

Note that this should not result in any user-visible changes to the
documentation.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-01-21 12:56:06 -08:00