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[PATCH 0/5] A natural solution to the @ -> HEAD problem

From
Ramkumar Ramachandra <artagnon@gmail.com>
Date
May 1, 2013, 16:20 UTC
Message-ID
<1367425235-14998-1-git-send-email-artagnon@gmail.com>
Hi,

Felipe's approach to solving the problem is a recursive reinterpret() that relies on parsing the sequence @[^{]. Seems like quite a contrived hack, and I think we can do much better than this.

Here, I present my approach to solving the problem. It interprets @ just like a ref in resolve_ref_unsafe(), after everything else has been peeled off; the solution is just the few simple lines shown in [5/5].

The core of the series tackles refactoring the @-parsing so that [5/5] becomes possible without doing anything contrived. [1/5] introduces the problem I started solving: making symbolic refs work properly. [2/5] and [3/5] are a result of me reading through the horrible @-parsing code. [4/5] finally solves the symbolic ref problem, and [5/5] becomes trivial.

A side-effect of the series is that you can now do:
    $ git symbolic-ref H HEAD
    $ git show H@{u}

In other words, symbolic refs actually work now and you can use them to achieve a lot of custom overrides. I think it is a step in the right direction.

Thanks for listening, and hope you enjoy reading the series as much as I enjoyed writing it.

Ramkumar Ramachandra (5):
  t1508 (at-combinations): more tests; document failures
  sha1_name.c: don't waste cycles in the @-parsing loop
  sha1_name.c: simplify @-parsing in get_sha1_basic()
  remote.c: teach branch_get() to treat symrefs other than HEAD
  refs.c: make @ a pseudo-ref alias to HEAD
 Documentation/git-check-ref-format.txt |  2 +
 Documentation/revisions.txt            |  8 +++-
 refs.c                                 | 12 ++++-
 remote.c                               | 14 ++++++
 sha1_name.c                            | 85 +++++++++++++++++++++++++---------
 t/t1400-update-ref.sh                  |  3 ++
 t/t1508-at-combinations.sh             | 15 ++++++
 7 files changed, 113 insertions(+), 26 deletions(-)
-- 
1.8.3.rc0.24.g6456091
Next: Ramkumar Ramachandra
Message 1 of 49 in “A natural solution to the @ -> HEAD problem”
  1. 0/5 A natural solution to the @ -> HEAD problemRamkumar Ramachandra, May 1, 2013
  2. 1/5 t1508 (at-combinations): more tests; document failuresRamkumar Ramachandra, May 1, 2013
  3. Junio C HamanoMay 1, 2013
  4. Ramkumar RamachandraMay 1, 2013
  5. Jeff KingMay 1, 2013
  6. Ramkumar RamachandraMay 1, 2013
  7. Junio C HamanoMay 1, 2013
  8. Felipe ContrerasMay 2, 2013
  9. Ramkumar RamachandraMay 2, 2013
  10. Felipe ContrerasMay 2, 2013
  11. Ramkumar RamachandraMay 2, 2013
  12. Ramkumar RamachandraMay 2, 2013
  13. Felipe ContrerasMay 2, 2013
  14. Ramkumar RamachandraMay 2, 2013
  15. Felipe ContrerasMay 2, 2013
  16. Ramkumar RamachandraMay 2, 2013
  17. Felipe ContrerasMay 2, 2013
  18. Ramkumar RamachandraMay 2, 2013
  19. David AguilarMay 4, 2013
  20. David AguilarMay 4, 2013
  21. 2/5 sha1_name.c: don't waste cycles in the @-parsing loopRamkumar Ramachandra, May 1, 2013
  22. Felipe ContrerasMay 1, 2013
  23. Ramkumar RamachandraMay 1, 2013
  24. Junio C HamanoMay 2, 2013
  25. 3/5 sha1_name.c: simplify @-parsing in get_sha1_basic()Ramkumar Ramachandra, May 1, 2013
  26. Felipe ContrerasMay 1, 2013
  27. Ramkumar RamachandraMay 1, 2013
  28. Jonathan NiederMay 1, 2013
  29. Ramkumar RamachandraMay 1, 2013
  30. Felipe ContrerasMay 1, 2013
  31. Ramkumar RamachandraMay 1, 2013
  32. Felipe ContrerasMay 1, 2013
  33. Ramkumar RamachandraMay 1, 2013
  34. Felipe ContrerasMay 1, 2013
  35. Ramkumar RamachandraMay 1, 2013
  36. 4/5 remote.c: teach branch_get() to treat symrefs other than HEADRamkumar Ramachandra, May 1, 2013
  37. Felipe ContrerasMay 1, 2013
  38. Ramkumar RamachandraMay 1, 2013
  39. Felipe ContrerasMay 1, 2013
  40. Ramkumar RamachandraMay 1, 2013
  41. Felipe ContrerasMay 1, 2013
  42. Ramkumar RamachandraMay 1, 2013
  43. Felipe ContrerasMay 1, 2013
  44. 5/5 refs.c: make @ a pseudo-ref alias to HEADRamkumar Ramachandra, May 1, 2013
  45. Felipe ContrerasMay 1, 2013
  46. Ramkumar RamachandraMay 1, 2013
  47. Felipe ContrerasMay 1, 2013
  48. Ramkumar RamachandraMay 1, 2013
  49. Ramkumar RamachandraMay 1, 2013

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