Posted on Mi 25 Februar 2009

Having fun with bzr

#nocomments y

So I wanted to hack proper channel mapping query support into libsndfile, something I have had on my TODO list for years. The first step was to find the source code repository for it. That was easy. Alas the VCS used is bzr. There are some very vocal folks on the Internet who claim that the bzr user interface is stupendously easy to use in contrast to git which apparantly is the very definition of complexity. And if it is stated on the Internet it must be true. I think I mastered git quite well, so yeah, checking out the sources with bzr can't be that difficult for my limited brain capacity.

So let's do what Erik suggests for checking out the sources:

$ bzr get

Calling this I get a nice percentage counter that starts at 0% and ends at, ... uh, 0%. That gives me a real feeling of progress. It takes a while, and then I get an error:

bzr: ERROR: Not a branch: "".

Now that's a useful error message. They even include an all-caps word! I guess that error message is right -- it's not a branch, it is a repository. Or is it not?

So what do we do about this? Maybe get is not actually the right verb. Let's try to play around a bit. Let's use the verb I use to get sources with in git:

$ bzr clone

Hmm, this results in exactly same 0% to 0% progress counter, and the same useless error message.

Now I remember that bzr is actually more inspired by Subversion's UI than by git's, so let's try it the SVN way.

$ bzr checkout

Hmm, and of course, I get exactly the same results again. A counter that counts from 0% to 0% and the same useless error message.

Ok, maybe that error is bzr's standard reply? Let's check this out:

$ bzr waldo
bzr: ERROR: unknown command "waldo"

Apparently not. bzr actually knows more than one error message.

Ok, I admit doing this by trial-and-error is a rather lame approach. RTFM! So let's try this.

$ man bzr-get
No manual entry for bzr-get

Ouch. No man page? How awesome. Ah, wait, maybe they have only a single unreadable mega man page for everything. Let's try this:

$ man bzr

Wow, this actually worked. Seems to list all commands. Now let's look for the help on bzr get:

/bzr get
Pattern not found  (press RETURN)

Hmm, no documentation for their most important command? That's weird! Ok, let's try it again with our git vocabulary:

/bzr clone
Pattern not found  (press RETURN)

Ok, this not funny anymore. Apparently the verbs are listed in alphabetical order. So let's browse to the letter g as in get. However it doesn't exist. There's bzr export, and then the next entry is bzr help (Oh, irony!) -- but no get in-between.

Ok, enough of this shit. Maybe the message wants to tell us that the repo actually doesn't exist (even though it confusingly calls it a "branch"). Let's go back to the original page at Erik's site and read things again. Aha, the "main archive archive can be found at (yes, the directory looks empty, but it isn't):". Hmm, indeed -- that URL looks very empty when it is accessed. How weird though that in bzr a repo is an empty directory!

And at this point I gave up and downloaded the tarball to make my patches against. I have still not managed to check out the sources from the repo. Somehow I get the feeling the actual repo really isn't available anymore under that address.

So why am I blogging about this? Not so much to start another flamefest, to nourish the fanboys, nor because it is so much fun to bash other people's work or simply to piss people off. It's more for two reasons:

Firstly, simply to make the point that folks can claim a thousand times that git's UI sucks and bzr's UI is awesome. It's simply not true. From what I experienced it is not the tiniest bit better. The error messages useless, the documentation incomplete, the interfaces surprising and exactly as redundant as git's. The only effective difference I noticed is that it takes a bit longer to show those error messages with bzr -- the Python tax. To summarize this more positively: git excels as much as bzr does. Both' documentation, their error messages and their user interface are the best in their class. And they have all the best chances for future improvement.

And the second reason of course is that I'd still like to know what the correct way to get the sources is. But for that I should probably ask Erik himself.

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