[PATCH v2 1/5] doc: BreakingChanges: transform to a manpage

From: Kristoffer Haugsbakk <code@khaugsbakk.name>

The breaking changes document is not a regular Git documentation page. That means that you cannot navigate to the doc with git(1), i.e. with:

    git help BreakingChanges

You instead have to download the Git project source. Or go to git-scm.com.[1] Then you get this disclaimer:[2]

    This information is specific to the Git project

    Please note that this information is only relevant to you if you
    plan on contributing to the Git project itself. It is in no shape or
    form required reading for regular Git users.

But this document is relevant to *all* Git users. Everyone should have as easy access to it as the other doc and guide pages.

To that end, let’s move the text to a new manpage gitbreaking-changes(7) in two steps:

1. Transform this document without renaming it (this step)
2. Rename it to gitbreaking-changes(7). But resurrect BreakingChanges in
   order to add a line linking to the new manpage (We wouldn’t want to
   break any readers)

Just do the minimal changes for the new format. Also demote the first section to the second level, i.e. make “Introduction” the same level as “Procedure’.

Step two is for the next commit.

† 1: https://git-scm.com/docs/BreakingChanges.html
† 2: Which I first mentioned in 098230f7 (you-still-use-that??: help the
     user help themselves, 2025-09-17), footnote #1.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
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 Documentation/BreakingChanges.adoc | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)