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

Re: [PATCH] git-p4: parse marshal output "p4 -G" in p4 changes

From
Miguel Torroja <miguel.torroja@gmail.com>
Date
Jul 13, 2017, 07:12 UTC
Message-ID
<CAKYtbVaxR0sdL_k=vy-aT5wEzvCTzDcM6Q-i0hO6jLMzjEUwmA@mail.gmail.com>
In-Reply-To
<xmqqr2xl1suy.fsf@gitster.mtv.corp.google.com>
Thanks,
I've just sent in reply to your previous e-mail three different patches.
* The first patch is just to show some broken tests,
* Second patch is to fix the original issue I had (the one that
initiated this thread)
* Third patch is the one that filters out "info" messages in p4CmdList
(this time default is reversed and set to False, what is the original
behaviour). The two test cases that are cured with this change have to
set explicitely skip_info=True.
On Wed, Jul 12, 2017 at 7:13 PM, Junio C Hamano <gitster@pobox.com> wrote:
Show 98 quoted lines
> Miguel Torroja <miguel.torroja@gmail.com> writes:
>
>> The motivation for setting skip_info default to True is because any
>> extra message  output by a p4 trigger to stdout, seems to be reported
>> as {'code':'info'} when the p4 command output is marshalled.
>>
>> I though it was the less intrusive way to filter out the verbose
>> server trigger scripts, as some commands are waiting for a specific
>> order and size of the list returned e.g:
>>
>>  def p4_last_change():
>>      results = p4CmdList(["changes", "-m", "1"])
>>      return int(results[0]['change'])
>>  .
>>  def p4_describe(change):
>>     ds = p4CmdList(["describe", "-s", str(change)])
>>     if len(ds) != 1:
>>         die("p4 describe -s %d did not return 1 result: %s" % (change, str(ds)))
>>
>> Previous examples would be broken if we allow extra "info" marshalled
>> messages to be exposed.
>>
>> In the case of the command that was broken with the new default
>> behaviour , when calling modfyChangelistUser, it is waiting for any
>> message with 'data' that is not an error to consider command was
>> succesful
>
> I somehow feel that this logic is totally backwards.  The current
> callers of p4CmdList() before your patch did not special case an
> entry that was marked as 'info' in its 'code' field.  Your new
> caller, which switched from using p4_read_pipe_lines() to p4CmdList()
> is one caller that you *know* wants to special case such an entry
> and wanted to skip.
>
> Your original patch that was queued to 'pu' for a while and then
> ejected from it after Travis saw an issue *assumed* that all other
> callers to p4CmdList() also want to special case such an entry, and
> that is why it made skip_info parameter default to True.
>
> The difference between knowing and assuming is the cause of the bug
> your original patch introduced into modifyChangelistUser().
>
> The way I read Luke's suggestion was that you can avoid making the
> same mistake by not changing the behaviour for existing callers you
> didn't look at.
>
> Instead of assuming everybody else do not want an entry with 'code'
> set to 'info', assume all the callers before your patch is doing
> fine, and when you *know* some of them are better off ignoring such
> an entry, explicitly tell them to do so, by:
>
>  * The first patch adds skip_info parameter that defaults to False
>    to p4CmdList() and do the special casing when it is set to True.
>
>  * The second patch updates p4ChangesForPaths() to use the updated
>    p4CmdList() and pass skip_info=True.  It is OK to squash this
>    step into the first patch.
>
>  * The third and later patches, if you need them, each examines an
>    existing caller of p4CmdList(), and add a new test to demonstrate
>    the existing breakage that comes from not ignoring an entry whose
>    'code' is 'info'.  That test would serve as a good documentation
>    to explain why it is better for the caller to pass skip_info=True,
>    so the same patch would also update the code to do so.
>
> While I was thinking the above through, here are a few cosmetic
> things that I noticed.  There is another comma that is not followed
> by a space in existing code that might want to be corrected in a
> clean-up patch but that is totally outside of the scope of this
> series.
>
> Thanks.
>
>  git-p4.py | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/git-p4.py b/git-p4.py
> index 1facf32db7..0d75753bce 100755
> --- a/git-p4.py
> +++ b/git-p4.py
> @@ -1501,7 +1501,7 @@ class P4Submit(Command, P4UserMap):
>          c['User'] = newUser
>          input = marshal.dumps(c)
>
> -        result = p4CmdList("change -f -i", stdin=input,skip_info=False)
> +        result = p4CmdList("change -f -i", stdin=input, skip_info=False)
>          for r in result:
>              if r.has_key('code'):
>                  if r['code'] == 'error':
> @@ -1575,7 +1575,7 @@ class P4Submit(Command, P4UserMap):
>                  files_list.append(value)
>                  continue
>          # Output in the order expected by prepareLogMessage
> -        for key in ['Change','Client','User','Status','Description','Jobs']:
> +        for key in ['Change', 'Client', 'User', 'Status', 'Description', 'Jobs']:
>              if not change_entry.has_key(key):
>                  continue
>              template += '\n'
Previous: Miguel TorrojaNext: Junio C Hamano
Message 30 of 31 in “git-p4: changelist template with p4 -G change -o”
  1. git-p4: changelist template with p4 -G change -oMiguel Torroja, Jun 20, 2017
  2. Junio C HamanoJun 22, 2017
  3. Luke DiamandJun 24, 2017
  4. miguel torrojaJun 24, 2017
  5. Lars SchneiderJun 24, 2017
  6. miguel torrojaJun 27, 2017
  7. git-p4: parse marshal output "p4 -G" in p4 changesMiguel Torroja, Jun 27, 2017
  8. Junio C HamanoJun 28, 2017
  9. Luke DiamandJun 28, 2017
  10. miguel torrojaJun 28, 2017
  11. miguel torrojaJun 29, 2017
  12. Luke DiamandJun 30, 2017
  13. miguel torrojaJun 30, 2017
  14. git-p4: parse marshal output "p4 -G" in p4 changesMiguel Torroja, Jun 29, 2017
  15. Lars SchneiderJun 30, 2017
  16. Miguel TorrojaJun 30, 2017
  17. Lars SchneiderJun 30, 2017
  18. Miguel TorrojaJun 30, 2017
  19. Miguel TorrojaJul 3, 2017
  20. git-p4: parse marshal output "p4 -G" in p4 changesMiguel Torroja, Jul 3, 2017
  21. Luke DiamandJul 11, 2017
  22. Miguel TorrojaJul 11, 2017
  23. git-p4: parse marshal output "p4 -G" in p4 changesMiguel Torroja, Jul 11, 2017
  24. Luke DiamandJul 12, 2017
  25. Miguel TorrojaJul 12, 2017
  26. Junio C HamanoJul 12, 2017
  27. 1/3 git-p4: git-p4 tests with p4 triggersMiguel Torroja, Jul 13, 2017
  28. 2/3 git-p4: parse marshal output "p4 -G" in p4 changesMiguel Torroja, Jul 13, 2017
  29. 3/3 git-p4: filter for {'code':'info'} in p4CmdListMiguel Torroja, Jul 13, 2017
  30. Miguel TorrojaJul 13, 2017
  31. Junio C HamanoJul 13, 2017

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.