[PATCH 0/2] shallow: handling fetch relative-deepen

When a shallowed repository gets deepened beyond the beginning of a merged branch, we may endup with some shallows, that are behind the reachable ones. Added test 'fetching deepen beyond merged branch' exposes that behaviour.

On the other hand, it seems that equivalent absolute depth driven fetches result in all the correct shallows. That led to this proposal, which unifies absolute and relative deepening in a way that the same get_shallow_commits() call is used in both cases. The difference is only that depth is adapted for relative deepening by measuring equivalent depth of current local shallow commits in the current remote repo. Thus a new function get_shallows_depth() has been added and the function get_reachable_list() became redundant / removed.

The get_shallows_depth() function also shares the logic of the get_shallow_commits() function, but it focuses on counting depth of each existing shallow commit. The minimum result is stored as 'data->deepen_relative', which is set not to be zero for relative deepening anyway. That way we can allways summ 'data->deepen_relative' and 'depth' values, because 'data->deepen_relative' is always 0 in absolute deepening.

Samo Pogačnik (2):
  shallow: free local object_array allocations
  shallow: handling fetch relative-deepen

 shallow.c             |   1 +
 t/t5500-fetch-pack.sh |  24 +++++++
 upload-pack.c         | 142 +++++++++++++++++++++++-------------------
 3 files changed, 103 insertions(+), 64 deletions(-)

base-commit: f0ef5b6d9bcc258e4cbef93839d1b7465d5212b9
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-2121%2Fspog%2Ffix-fetch-deepen-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-2121/spog/fix-fetch-deepen-v1
Pull-Request: https://github.com/git/git/pull/2121