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Re: [PATCH v3 01/10] built-in add -i/-p: treat SIGPIPE as EOF

From
Jeff King <peff@peff.net>
Date
Jan 15, 2020, 19:03 UTC
Message-ID
<20200115190322.GA4087422@coredump.intra.peff.net>
In-Reply-To
<xmqqblr4k1t0.fsf@gitster-ct.c.googlers.com>
On Wed, Jan 15, 2020 at 10:32:59AM -0800, Junio C Hamano wrote:
Show 19 quoted lines
> >>   test_config interactive.diffFilter "cat >/dev/null ; echo too-short" &&
> >> 
> >> made the test reliable, with over 2000 --stress repetitions, and that
> >> with only a single "y" on 'git add's stdin.
> >
> > Yeah, I agree the test should be changed. What you wrote above was my
> > first thought, too, but I think "sed 1d" is actually a more realistic
> > test (and is shorter and one fewer process).
> 
> I am not sure what we are aiming for.  Are we making sure the
> command behaves well in the hands of end users, who may write a
> script that consumes only early parts of the input that is needed
> for its use and stops reading, or are we just aiming to claim "all
> our tests pass"?  I was hoping that we would be doing the former,
> and I would understand if the suggestion were "sed 1q" for that
> exact reason.
> 
> IOW, shouldn't we be fixing the part that drives the external
> process, so that the test "passes" even with such a "broken" filter?

The original motivation for this test (and the code that fixes it) was diff-so-fancy, which read all of the input but didn't have a 1:1 line correspondence in the output (IIRC it condensed some particular lines, like rename from/to into a single line).

And I think most sane filters would end up reading all of the content. Or a misconfiguration would cause them to read nothing at all.

So something like "sed 1d" is more representative of a real filter. If we want to test SIGPIPE, then the current one that reads _nothing_ is the most torturous. But "sed 1q" is neither realistic (if that's what we're going for) nor the hardest thing we can throw at the code (if that's what we want).

Show 6 quoted lines
> > I've been tempted to say that we should just ignore SIGPIPE everywhere,
> > and convert even copious-output programs like git-log to just check for
> > errors (they could probably even just check ferror(stdout) for each
> > commit we output, if we didn't want to touch every printf call).
> 
> Yeah, I share that temptation.

Hmm. My recollection was that you were more of a fan of SIGPIPE than I am. But if you agree, then maybe the time has come for action. :)

-Peff
Previous: Junio C HamanoNext: Johannes Schindelin
Message 40 of 63 in “built-in add -p: add support for the same config settings as the Perl version”
  1. 0/9 built-in add -p: add support for the same config settings as the Perl versionJohannes Schindelin via GitGitGadget, Dec 21, 2019
  2. 1/9 built-in add -p: support interactive.diffFilterJohannes Schindelin via GitGitGadget, Dec 21, 2019
  3. 2/9 built-in add -p: handle diff.algorithmJohannes Schindelin via GitGitGadget, Dec 21, 2019
  4. 6/9 built-in add -p: respect the `interactive.singlekey` config settingJohannes Schindelin via GitGitGadget, Dec 21, 2019
  5. 8/9 built-in add -p: handle Escape sequences more efficientlyJohannes Schindelin via GitGitGadget, Dec 21, 2019
  6. 4/9 terminal: accommodate Git for Windows' default terminalJohannes Schindelin via GitGitGadget, Dec 21, 2019
  7. 3/9 terminal: make the code of disable_echo() reusableJohannes Schindelin via GitGitGadget, Dec 21, 2019
  8. 7/9 built-in add -p: handle Escape sequences in interactive.singlekey modeJohannes Schindelin via GitGitGadget, Dec 21, 2019
  9. 5/9 terminal: add a new function to read a single keystrokeJohannes Schindelin via GitGitGadget, Dec 21, 2019
  10. 9/9 ci: include the built-in `git add -i` in the `linux-gcc` jobJohannes Schindelin via GitGitGadget, Dec 21, 2019
  11. SZEDER GáborDec 21, 2019
  12. Johannes SchindelinDec 25, 2019
  13. Junio C HamanoDec 22, 2019
  14. Johannes SchindelinDec 25, 2019
  15. Junio C HamanoDec 24, 2019
  16. Junio C HamanoDec 24, 2019
  17. Simon RuderichDec 25, 2019
  18. Johannes SchindelinDec 25, 2019
  19. Johannes SchindelinDec 25, 2019
  20. 0/9 built-in add -p: add support for the same config settings as the Perl versionJohannes Schindelin via GitGitGadget, Dec 25, 2019
  21. 1/9 built-in add -p: support interactive.diffFilterJohannes Schindelin via GitGitGadget, Dec 25, 2019
  22. SZEDER GáborJan 7, 2020
  23. Johannes SchindelinJan 13, 2020
  24. 2/9 built-in add -p: handle diff.algorithmJohannes Schindelin via GitGitGadget, Dec 25, 2019
  25. 3/9 terminal: make the code of disable_echo() reusableJohannes Schindelin via GitGitGadget, Dec 25, 2019
  26. 4/9 terminal: accommodate Git for Windows' default terminalJohannes Schindelin via GitGitGadget, Dec 25, 2019
  27. 6/9 built-in add -p: respect the `interactive.singlekey` config settingJohannes Schindelin via GitGitGadget, Dec 25, 2019
  28. 8/9 built-in add -p: handle Escape sequences more efficientlyJohannes Schindelin via GitGitGadget, Dec 25, 2019
  29. 9/9 ci: include the built-in `git add -i` in the `linux-gcc` jobJohannes Schindelin via GitGitGadget, Dec 25, 2019
  30. Derrick StoleeDec 26, 2019
  31. Johannes SchindelinJan 1, 2020
  32. 7/9 built-in add -p: handle Escape sequences in interactive.singlekey modeJohannes Schindelin via GitGitGadget, Dec 25, 2019
  33. 5/9 terminal: add a new function to read a single keystrokeJohannes Schindelin via GitGitGadget, Dec 25, 2019
  34. Junio C HamanoDec 26, 2019
  35. 00/10 built-in add -p: add support for the same config settings as the Perl versionJohannes Schindelin via GitGitGadget, Jan 13, 2020
  36. 01/10 built-in add -i/-p: treat SIGPIPE as EOFJohannes Schindelin via GitGitGadget, Jan 13, 2020
  37. SZEDER GáborJan 13, 2020
  38. Jeff KingJan 13, 2020
  39. Junio C HamanoJan 15, 2020
  40. Jeff KingJan 15, 2020
  41. Johannes SchindelinJan 14, 2020
  42. SZEDER GáborJan 17, 2020
  43. Jeff KingJan 17, 2020
  44. 02/10 built-in add -p: support interactive.diffFilterJohannes Schindelin via GitGitGadget, Jan 13, 2020
  45. 03/10 built-in add -p: handle diff.algorithmJohannes Schindelin via GitGitGadget, Jan 13, 2020
  46. 05/10 terminal: accommodate Git for Windows' default terminalJohannes Schindelin via GitGitGadget, Jan 13, 2020
  47. 04/10 terminal: make the code of disable_echo() reusableJohannes Schindelin via GitGitGadget, Jan 13, 2020
  48. 06/10 terminal: add a new function to read a single keystrokeJohannes Schindelin via GitGitGadget, Jan 13, 2020
  49. 07/10 built-in add -p: respect the `interactive.singlekey` config settingJohannes Schindelin via GitGitGadget, Jan 13, 2020
  50. 10/10 ci: include the built-in `git add -i` in the `linux-gcc` jobJohannes Schindelin via GitGitGadget, Jan 13, 2020
  51. 09/10 built-in add -p: handle Escape sequences more efficientlyJohannes Schindelin via GitGitGadget, Jan 13, 2020
  52. 08/10 built-in add -p: handle Escape sequences in interactive.singlekey modeJohannes Schindelin via GitGitGadget, Jan 13, 2020
  53. 00/10 built-in add -p: add support for the same config settings as the Perl versionJohannes Schindelin via GitGitGadget, Jan 14, 2020
  54. 01/10 t3701: adjust difffilter testJohannes Schindelin via GitGitGadget, Jan 14, 2020
  55. 02/10 built-in add -p: support interactive.diffFilterJohannes Schindelin via GitGitGadget, Jan 14, 2020
  56. 05/10 terminal: accommodate Git for Windows' default terminalJohannes Schindelin via GitGitGadget, Jan 14, 2020
  57. 08/10 built-in add -p: handle Escape sequences in interactive.singlekey modeJohannes Schindelin via GitGitGadget, Jan 14, 2020
  58. 10/10 ci: include the built-in `git add -i` in the `linux-gcc` jobJohannes Schindelin via GitGitGadget, Jan 14, 2020
  59. 07/10 built-in add -p: respect the `interactive.singlekey` config settingJohannes Schindelin via GitGitGadget, Jan 14, 2020
  60. 03/10 built-in add -p: handle diff.algorithmJohannes Schindelin via GitGitGadget, Jan 14, 2020
  61. 06/10 terminal: add a new function to read a single keystrokeJohannes Schindelin via GitGitGadget, Jan 14, 2020
  62. 04/10 terminal: make the code of disable_echo() reusableJohannes Schindelin via GitGitGadget, Jan 14, 2020
  63. 09/10 built-in add -p: handle Escape sequences more efficientlyJohannes Schindelin via GitGitGadget, Jan 14, 2020

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