[darcs-devel] [issue516] pull incorrectly reports no new patches

[Zooko]

New submission from Zooko <zooko at zooko.com>:

Dear darcs hackers:

There follows an edited version of a conversation I had with Arno on  
IRC.  He went to bed before I could get him to try to reproduce the  
problem.

-------
arnowa: did i mention already that i hate darcs?
arnowa: i mean "darcs pull" i supposed to integrate new patches from  
the repo into my tree, no?
arnowa: and what to do if it does not?
zooko: Hello!
zooko: Yes, it is.
zooko: (Yes, you did.)
zooko: So, what goes wrong?
zooko: What did darcs do when you tried to "pull" earlier?
arnowa: it told that there was nothing new. which is not true at all
arnowa: yesterday after several pulls repairs, and so on, it always  
said nothing new and all consistent, but suddenly the changes were  
there.
arnowa: today that trick does not help either.
arnowa: when does tahoe switch to a working darcs-replacement?
zooko: I'm not sure when.
zooko: I remember you had a problem with darcs and then, if I recall  
correctly, you did a fresh "darcs get http://allmydata.org/source/ 
tahoe/trunk".
zooko: And then, did the problem stop happening when you used the  
repository that resulted from that fresh get?
zooko: And then, did the problem or a problem start happening again?
zooko: Next time you see Brian Warner ("warner" on IRC) then ask him  
when tahoe will switch to a different tool.
arnowa: yes, and i did two other fresh darcs get in the meanwhile,  
since those probs emerged again, and again.
zooko: Last time I asked him he said he wanted to get more experience  
using mercurial and bazaar before deciding whether to switching tahoe  
to one of them.
zooko: Hmmmmm.
arnowa: looks somewhat different each time, but the "no news" bug  
repeats itself now
zooko: What problem happens?
arnowa: mercurial is in cygwin
zooko: Do you know which repository it is pulling from when you run  
"darcs pull".
zooko: Interesting detail -- mercurial is in cygwin.  bzr isn't?
arnowa: the one you quoted above
arnowa: is there another?
arnowa: don't know about bzr
• arnowa looks
zooko: So if you explicitly name that one on the cmdline, with this:  
"darcs pull http://allmydata.org/source/tahoe/trunk"
zooko: then what does it say?
zooko: And of course you should execute that cmdline from inside the  
darcs repo of yours, e.g. from the directory which contains the  
_darcs subdir.
arnowa: can't we use something well-known to work, like git or svn?
arnowa: same prob
zooko: git doesn't work at all on windows!
zooko: Does it?
zooko: svn we could use.  Ask Brian.  :-)
zooko: So when you do that pull then it says
arnowa: it gives the normal message when there are no new patches
zooko: Okay, it says "No remote changes to pull in!"
arnowa: git works on cygwin
zooko: Now how do you know that there are new patches that you don't  
yet have?
zooko: It does?  Fascinating.
• zooko looks at the trac timeline.
zooko: Here is the trac timeline:
zooko: http://allmydata.org/trac/tahoe/timeline
cryptomonkey: A; http://allmydata.org/trac/tahoe/timeline from zooko
zooko: And here is the darcs.cgi patch browser:
zooko: http://allmydata.org/darcs.cgi/tahoe/?c=patches
cryptomonkey: B; http://allmydata.org/darcs.cgi/tahoe/?c=patches from  
zooko
zooko: So the most recent patch that is listed there is "webapi.txt:  
put back the manifest feature".
zooko: Are you saying that you don't have that patch but that pull  
doesn't offer it to you?
arnowa: i am missing 20+ patches
zooko: The most recent 20+?
arnowa: yes
zooko: Okay, so what's the most recent patch that you have in your  
local repo?  "darcs changes 2>&1 | less"
arnowa: in --> across
arnowa: aha, your darcs binary suddenly works when called from dos  
prompt !?!
zooko: Aha!
zooko: So if you do "darcs pull"
zooko: from a cygwin bash shell, it does differently than if you do  
it from cmd.exe ??
zooko: And what it does in the former case is write "No remote  
changes to pull in!" ?
arnowa: yes
zooko: Argh.
zooko: You are executing "darcs", which is my bash script that itself  
executes realdarcs.exe, right?
• arnowa might happen to recall to already have mentioned not being  
too much motivated to debug a non-foolproof rcs, indead
zooko: Okay, so you're not motivated to help me debug it.  Damn.
zooko: That's really strange behavior.  It sounds like it could be a  
bug in my bash script, but I don't see how it could happen and I've  
not heard about this bug before.
arnowa: sorry,but that is not my cup of tea, and even though this  
<...snip...> darcs thing is around here since years, i still don't  
speak haskell
zooko: Well, this bug is unlikely to involve any haskell.  It is  
probably a bug in my script, which is written in bash.
zooko: Oooh.
zooko: I have an idea.
zooko: I'll bet that the ">" char in that patch name got used by my  
bash script and caused bash to do a redirect...  No...  No...
zooko: Gr...
zooko: I'll experiment with that patch in my cygwin...
arnowa: i won't say it worked in dos and did not in cygwin, since  
yesterday it also suddenly worked, but in cygwin
zooko: What?  You did a "pull" in bash and it did the "No new  
patches" thing, and then you did it again and it gave you new patches?
arnowa: and, no, there was no sign for any errors in the wrapper, or  
the like
zooko: Maybe that was because there *weren't* actually any new  
patches the first time?
arnowa: yesterday it said "no new patches", and after several of  
them, i found out that the tree had gotten patched somewhen.
arnowa: no, there were, according to the website
arnowa: as now i got 33 patches suddenly
zooko: So the way it happened this time was that you did a darcs pull  
from cmd.exe, right?
arnowa: yes
arnowa: the --> patch was the last one i had before, BTW
• zooko nods.
• zooko thinks.
zooko: Are you sure you're running the darcs that you got from my web  
site?
zooko: Is the "darcs" executable a bash script?
zooko: Does "darcs --version" say
zooko: 1.0.9 (release)
arnowa: yes, yes
zooko: What does "darcs check" say?
arnowa: all consistent. it always says that
zooko: That is really perplexing.  I've reported hundreds of darcs  
bugs and observed hundreds more darcs bug reports
zooko: ( http://bugs.darcs.net )
zooko: and I can't figure out how this one could happen.
arnowa: i would guess it is not a dos/cygwin thing
zooko: Hm.
zooko: Well, could you send an e-mail to "bugs at darcs.net" saying what  
happened?
arnowa: i would guess it is primarily a sign for darcs not being fool- 
proof enough for usage. period.
zooko: Well, please do ask Brian next time you see him what he thinks  
we should do for revision control...
arnowa: can't we use that time we are about to debug darcs in  
switching to svn or git or whatever (i would even sf.net's nice CVS  
over that darcs situation now)
zooko: But in addition to that, it would be interesting if you  
reported this bug to the darcs developers.
arnowa: i am pretty sure not to be able to provide reproducable  
information
• zooko nods.
zooko: Still it would be good to report what you know.
zooko: So, as for replacement systems, I'm mostly inclined to do  
whatever Brian wants.
zooko: But I also have been paying attention to the topic recently.
zooko: I would be most interested in mercurial or bazaar.
arnowa: so what would be your preference?
arnowa: ah
arnowa: and for what reasons?
zooko: svn (and cvs) have known limitations that would be irritating
zooko: git is hard to use, linux-centric, written in C
arnowa: git is in cygwin
zooko: mercurial ("hg") and bzr are written in Python
• zooko nods.
arnowa: but if it works, the language does not mater, does it?
zooko: Yes, I agree.
zooko: So, if you don't want to write a message to "bugs at darcs.net"  
then I will write one and extract some quotes from this IRC log, okay?
arnowa: i am not really fond of git, except for it seems very  
stable... it seems defintely hard to use...
arnowa: okay
zooko: Oh, could you do a couple of more experiments?  Add "-v -v -v"  
to the "darcs pull" command.
arnowa: need to sleep now, sorry
zooko: Oh, but now that you've successfully pulle...
zooko: Okay!  Sleep well!
arnowa: same output as usual. except for it might be true in the moment
arnowa: bye!
zooko: Right.
zooko: Later!
arnowa is now known as arnotootired.

----------
messages: 2037
nosy: beschmi, droundy, kowey, tommy, zooko
status: unread
title: pull incorrectly reports no new patches

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Darcs bug tracker <bugs at darcs.net>
<http://bugs.darcs.net/issue516>
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