branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
#require bzr
$ . "$TESTDIR/bzr-definitions"
The file/directory replacement can only be reproduced on
bzr >= 1.4. Merge it back in test-convert-bzr-directories once
this version becomes mainstream.
replace file with dir
$ mkdir test-replace-file-with-dir
$ cd test-replace-file-with-dir
$ brz init -q source
$ cd source
$ echo d > d
$ brz add -q d
$ brz commit -q -m 'add d file'
$ rm d
$ mkdir d
$ brz add -q d
$ brz commit -q -m 'replace with d dir'
$ echo a > d/a
$ brz add -q d/a
$ brz commit -q -m 'add d/a'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
2 add d file
1 replace with d dir
0 add d/a
$ manifest source-hg tip
% manifest of tip
644 d/a
$ cd source-hg
$ hg update
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../..