> On Jul 3, 2018, at 3:27 PM, Elijah Newren <newren@xxxxxxxxx> wrote: > > Hi Philip, > > On Tue, Jul 3, 2018 at 1:40 PM, Philip Prindeville > <philipp_subx@xxxxxxxxxxxxxxxxxxxxx> wrote: >> Hi. >> >> I tried to import into git a repo that I was working on (because it just seemed easier), but when I tried to export the repo back out after making my changes I found it choking on a few things. >> >> It was explained to me (by the Bitkeeper folks) that git meta-data doesn’t accurately track file moves… If a file disappears from one place and reappears in another with the same contents, that’s assumed to be a move. >> >> Given that “git mv” is an explicit action, I’m not sure why that wouldn’t be explicitly tracked. > > Not a full explanation, but see > https://git-scm.com/book/en/v2/Git-Internals-Moving-Files Why not add the logic to track moves/renames? That link explains what it does, but not why it does it. > >> But I’ve not looked too closely under the covers about how git represents stuff, so maybe there’s more to it than I’m assuming. >> >> During an export using “-M” and “-C”, Bitkeeper complained: > > Why would you add -C? Does bitkeeper also track copies? I figure that I’d furnish the maximum amount of meta data, and bitkeeper would use what it could and ignore the rest. > >> fast-import: line 'R ports/winnt/libntp/nt_clockstuff.c ports/winnt/ntpd/nt_clockstuff.c' not supported >> >> so I tried removing those two options, and it got further, this time stalling on: >> >> fast-import: Unknown command: tag ntp-stable > > If the fast-import command you are using can't read tags, then perhaps > you should report that to the authors of the fast-import tool you are > using and/or only feed branches to your fast-export command. Well, I’ll just do branches for now… > >> I like git, mostly because I’ve used it a lot more… and I like the GitHub service. I use Bitkeeper because a few projects I work on are already set up to use it and it’s not my call whether it’s worth the effort to make the conversion or live with it. >> >> So… this is an appeal for both to play better together. >> >> What’s involved in getting git to track file/directory moves/renames so that it’s palatable to Bitkeeper? > > Not tracking file/directory moves/renames wasn't an oversight but a > fundamental design decision; see e.g. > https://public-inbox.org/git/Pine.LNX.4.64.0510211826350.10477@xxxxxxxxxxx/. "I'm convinced that git handles renames better than any other SCM ever. Exactly because we figure it out when it matters.” I disagree. When the move happens, there’s a commit message that goes along with that. There’s an insight into why the move is happening. That’s something that software can’t do for you. > > However, supposing that we did track renames, how would we tell > bitkeeper? Well, we'd print out a line that looks like this in the > fast-export: > > 'R ports/winnt/libntp/nt_clockstuff.c ports/winnt/ntpd/nt_clockstuff.c' > > which is precisely the line that bitkeeper's fast-import was choking > on. So, it sounds like they don't support importing rename > information (or at least the version of fast-import you're using > doesn't). I think this is where the bug is; you'll probably want to > report it to whoever maintains the fast-import command that is choking > on this line. Already done: https://users.bitkeeper.org/t/using-fast-import-from-git-into-bk/907 Not sure I understand the response: "The rename info that git gives us is a guess, that’s why there is that 0-100% next to it, that’s showing you how much of the two versions of the file were identical. So that info is unreliable, it’s just a guess." Okay, what’s stopping them from doing their best with the information provided, even if it is a guess? By the way, what happens when you interactively rebase a bunch of commits, change their order, and in the middle of an “edit”, do a “git mv … …” followed by a “git commit --amend && git rebase --continue”? -Philip > > Once that's fixed, you can export from git with the -M flag, and from > that output, there'll be no way to tell whether the original > repository tracked renames or detected them after the fact. > > > Hope that helps, > Elijah
