[PATCH v2 0/5] remote: announce removal of "branches/" and "remotes/"

Hi,

back when Git was in its infancy, remotes were configured via separate files in "branches/" (back in 2005). This mechanism was replaced later that year with the "remotes/" directory. These mechanism have evenutally been replaced by config-based remotes, and it is very unlikely that anybody still uses these directories to configure their remotes. Both of these directories have been marked as deprecated, one in 2005 and the other one in 2011.

This patch series follows through with the deprecation of these and announces them for removal in Git 3.0. Furthermore, it creates the infra to compile Git with such breaking changes enabled and wires up a CI job both for GitHub and GitLab to test those breaking changes.

The series is based on top caacdb5dfd (The fifteenth batch, 2024-12-10) with ps/build at 904339edbd (Introduce support for the Meson build system, 2024-12-06) merged into it.

Changes in v2:
- Some small fixes to the deprecation notice of "branches/" and
  "remotes/".
- Some small fixes to commit messages.
- Link to v1: https://lore.kernel.org/r/20241211-pks-remote-branches-deprecation-v1-0-1431e2369135@pks.im

Thanks!

Patrick

---
Patrick Steinhardt (5):
      Makefile: wire up build option for deprecated features
      ci: merge linux-gcc-default into linux-gcc
      ci: repurpose "linux-gcc" job for deprecations
      builtin/pack-redundant: remove subcommand with breaking changes
      remote: announce removal of "branches/" and "remotes/"

 .github/workflows/main.yml             |  6 +----
 .gitlab-ci.yml                         |  6 +----
 Documentation/BreakingChanges.txt      | 25 ++++++++++++++++++
 Documentation/gitrepository-layout.txt |  7 +++--
 GIT-BUILD-OPTIONS.in                   |  1 +
 Makefile                               |  7 +++++
 builtin/remote.c                       |  2 ++
 ci/lib.sh                              |  5 ----
 ci/run-build-and-tests.sh              |  3 ++-
 contrib/buildsystems/CMakeLists.txt    |  1 +
 git.c                                  |  2 ++
 meson.build                            |  6 +++++
 meson_options.txt                      |  2 ++
 remote.c                               |  6 +++++
 remote.h                               |  2 ++
 t/t5323-pack-redundant.sh              |  6 +++++
 t/t5505-remote.sh                      |  6 ++---
 t/t5510-fetch.sh                       | 13 ++++------
 t/t5515-fetch-merge-logic.sh           | 47 ++++++++++++++++++----------------
 t/t5516-fetch-push.sh                  | 14 +++++-----
 t/test-lib.sh                          |  4 +++
 21 files changed, 112 insertions(+), 59 deletions(-)

Range-diff versus v1:

1:  51bc2fc09e ! 1:  c15229fb98 Makefile: wire up build option for deprecated features
    @@ Commit message
         breaking changes in the Git project. In 2454970930 (BreakingChanges:
         early adopter option, 2024-10-11) we have amended the document a bit to
         mention that any introduced breaking changes must be accompanied by
    -    logic that allows us to easily enable the breaking change at runtime.
    +    logic that allows us to enable the breaking change at compile-time.
         While we already have two breaking changes lined up, neither of them has
         such a switch because they predate those instructions.
     
2:  71dc627473 = 2:  0131ac856f ci: merge linux-gcc-default into linux-gcc
3:  8134955d0b = 3:  38a71377c0 ci: repurpose "linux-gcc" job for deprecations
4:  aa986122ea = 4:  a8d18e3499 builtin/pack-redundant: remove subcommand with breaking changes
5:  b528488559 ! 5:  7445f06776 remote: announce removal of "branches/" and "remotes/"
    @@ Commit message
     
         Back when Git was in its infancy, remotes were configured via separate
         files in "branches/" (back in 2005). This mechanism was replaced later
    -    that year with the "remotes/" directory. These mechanism have evenutally
    +    that year with the "remotes/" directory. These mechanism have eventually
         been replaced by config-based remotes, and it is very unlikely that
         anybody still uses these directories to configure their remotes.
     
    @@ Documentation/BreakingChanges.txt: Cf. <xmqq1rjuz6n3.fsf_-_@gitster.c.googlers.c
     ++
     +As our documentation mentions, these directories are not to be found in modern
     +repositories at all and most users aren't even aware of these mechanisms. They
    -+have been deprecated for almost 20 years and 14 years respectively, and I am
    ++have been deprecated for almost 20 years and 14 years respectively, and we are
     +not aware of any reason why anybody would want to use these mechanisms.
    -+Furthermore, the ".git/branches/" directory is noadays misleadingly named and
    ++Furthermore, the ".git/branches/" directory is nowadays misleadingly named and
     +may cause confusion as "branches" are almost exclusively used in the context of
     +references.
     ++

--- base-commit: 713ec79a9091cec60b110d605b418904759982ab change-id: 20241205-pks-remote-branches-deprecation-037a4389a377