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Comment by luckydude

10 years ago

It tracks renames, it's not like git. Every file has an internal identifier, that's the actual file id, the name is a versioned attribute of the file.

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luckydude

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glandium  10 years ago

What's not clear from your replies is whether it tracks renames like mercurial, by having users run a manual command to ensure the VCS know about the rename. Except if bk has a file system monitor, I'll assume that's what it does. Unfortunately, data on a few Mercurial repositories I looked at (Mozilla's and Mercurial's) shows that people don't mark all file renames.

  • neandrake  10 years ago

    The only way I'm familiar with instructing mercurial to do this is with

        hg addremove -s

    Is there another way to indicate a rename?

hansihe  10 years ago

How does it detect renamed files in the filesystem?

Thank you for open sourcing by the way, I can definitely see how some features (binary file handling, submodule handling) could be useful for large-scale projects like games.

  • luckydude  10 years ago

    Each history file contains it's internal name, much like a file system has an inode # that is the internal name for that file. We call the names "keys" and you can dig out the inode key like so (every delta has a key, the first delta is called the rootkey):

        $ bk log -nd:ROOTKEY: -r+ slib.c
    lm@bitmover.com|src/slib.c|19970518232928|52808|f3733b2c327712e5

    The key is user@host|relative path|UTC|checksum|64 bits of /dev/random and they are guaranteed to be unique if your DNS config is correct (we don't create duplicate keys, look for the uniq db in the code).

    The way we version the entire tree is simple, it's logically (implemented differently for performance):

        <rootkey> <delta key>
    <rootkey> <delta key>
    ...

    where each rootkey uniquely identifies a file and each delta key identifies the tip as of that commit.

    Not sure if that is clear enough or not, ask away if not.

    • danielbot  10 years ago

      Not tracking namespace accurately is Git's biggest weakness and would most probably be BK's best argument for getting a tryout. With Git, renaming a file and editing it at the same time tends to make a mess of the history and cause much pain. You can say just don't do that, but I say it happens, and it should just work.

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