git/list[1] front-page[2] threads[3] people[4] search[5] about
 

Re: git status: small difference between stating whole repository and small subdirectory

From
Junio C Hamano <gitster@pobox.com>
Date
Feb 20, 2012, 22:04 UTC
Message-ID
<7v1uppkvpx.fsf@alter.siamese.dyndns.org>
In-Reply-To
<20120220203540.GA5966@sigill.intra.peff.net>
Jeff King <peff@peff.net> writes:
> ... Things may have changed since then, of course, but I at
> least know that they were sufficient in 34110cd^.

Looking at where cache_tree_free() is called, I think back then the two-way merge was deemed OK, but we did not trust three-way merge or merge-recursive at all.

> I think you can construct two tests that will both work in the "ideal"
> case. In the first one, you move to a tree that updates "foo", and
> therefore the root cache-tree is invalidated.

I have to warn you that under-invalidation of cache-tree is extremely hard to find. The only way I know, which I had to resort to when dealing with a handful of instances of under-invalidation bugs, is to run write-tree with potentially corrupt cache-tree and then using the same index but with the cache-tree purged, run another write-tree and check to see if two trees match.

Show 5 quoted lines
> In general, t0090 could benefit from using a larger tree. For example,
> the add test does "git add foo" and checks that the root cache-tree was
> invalidated. But it should _also_ check that the cache-tree for a
> subdirectory is _not_ invalidated (and it isn't; git-add does the right
> thing).

It is OK to check that we do not over-invalidate for performance, but it is a lot more important to make sure we do not under-invalidate for correctness. I am a bit worried that you seem to be putting more stress on the former.

Previous: Jeff KingNext: Jeff King
Message 30 of 52 in “git status: small difference between stating whole repository and small subdirectory”
  1. Piotr KrukowieckiFeb 10, 2012
  2. Nguyen Thai Ngoc DuyFeb 10, 2012
  3. Piotr KrukowieckiFeb 10, 2012
  4. Nguyen Thai Ngoc DuyFeb 10, 2012
  5. Piotr KrukowieckiFeb 13, 2012
  6. Piotr KrukowieckiFeb 10, 2012
  7. Thomas RastFeb 14, 2012
  8. Piotr KrukowieckiFeb 15, 2012
  9. Nguyen Thai Ngoc DuyFeb 15, 2012
  10. Piotr KrukowieckiFeb 15, 2012
  11. Piotr KrukowieckiFeb 16, 2012
  12. Jeff KingFeb 15, 2012
  13. Piotr KrukowieckiFeb 16, 2012
  14. Thomas RastFeb 16, 2012
  15. Junio C HamanoFeb 16, 2012
  16. Piotr KrukowieckiFeb 17, 2012
  17. Jeff KingFeb 16, 2012
  18. Piotr KrukowieckiFeb 17, 2012
  19. Jeff KingFeb 17, 2012
  20. Junio C HamanoFeb 17, 2012
  21. Jeff KingFeb 17, 2012
  22. Piotr KrukowieckiFeb 20, 2012
  23. Jeff KingFeb 20, 2012
  24. Thomas RastFeb 20, 2012
  25. Nguyen Thai Ngoc DuyFeb 20, 2012
  26. Jeff KingFeb 20, 2012
  27. Jeff KingFeb 20, 2012
  28. Thomas RastFeb 20, 2012
  29. Jeff KingFeb 20, 2012
  30. Junio C HamanoFeb 20, 2012
  31. Jeff KingFeb 20, 2012
  32. Junio C HamanoFeb 20, 2012
  33. Piotr KrukowieckiFeb 21, 2012
  34. Junio C HamanoFeb 20, 2012
  35. Jeff KingFeb 20, 2012
  36. Nguyen Thai Ngoc DuyFeb 21, 2012
  37. Junio C HamanoFeb 21, 2012
  38. Nguyen Thai Ngoc DuyFeb 22, 2012
  39. Junio C HamanoFeb 22, 2012
  40. Nguyen Thai Ngoc DuyFeb 22, 2012
  41. Thomas RastFeb 22, 2012
  42. Nguyen Thai Ngoc DuyFeb 22, 2012
  43. Junio C HamanoFeb 22, 2012
  44. Piotr KrukowieckiApr 10, 2012
  45. Junio C HamanoApr 10, 2012
  46. Jeff KingApr 10, 2012
  47. Junio C HamanoFeb 20, 2012
  48. Thomas RastFeb 20, 2012
  49. Nguyen Thai Ngoc DuyFeb 20, 2012
  50. Jeff KingFeb 20, 2012
  51. Junio C HamanoFeb 20, 2012
  52. Jeff KingFeb 20, 2012

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.