Order of merges and the appearance of the revision history

[Joseph Wakeling]

Something that's started to bother me is that revision history in bzr is
dependent not just on what patches are in the system but also on what
order merges and pulls happened.

I've attached a simple little shell script to show what I mean.  It
creates two divergent branches (1 and 2) and then clones each into a and
b copies.

1a merges from 2a, and 2a then pulls from 1a.

2b merges from 1b, and 1b then pulls from 2b.

Now, if we look at either an a branch or a b branch with bzr viz, the
revision history is topologically identical, but it's displayed
differently depending on the order of the merge.

Worse, bzr pull won't let me pull from a b branch to an a branch,
despite the fact that the _code_ is identical and so, topologically
speaking, is the revision history.

I wonder if anyone could give some insight into why this is and what
purpose it serves (if any).

    -- Joe
-------------- next part --------------
A non-text attachment was scrubbed...
Name: bzrtest.sh
Type: application/x-shellscript
Size: 657 bytes
Desc: not available
Url : https://lists.ubuntu.com/archives/bazaar/attachments/20070423/0cfedef3/attachment.bin