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.
====================================
Testing head checking code: Case A-4
====================================
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
This case is part of a series of tests checking this behavior.
Category A: simple case involving a branch being superseded by another.
TestCase 4: New changeset as children of the successor
.. old-state:
..
.. * 1-changeset branch
..
.. new-state:
..
.. * 2-changeset branch, first is a successor, but head is new
..
.. expected-result:
..
.. * push allowed
..
.. graph-summary:
..
.. ◔ B
.. |
.. A ø⇠◔ A'
.. |/
.. ●
$ . $TESTDIR/testlib/push-checkheads-util.sh
Test setup
----------
$ mkdir A4
$ cd A4
$ setuprepos
creating basic server and client repo
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd client
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit A1
created new head
$ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`
1 new obsolescence markers
obsoleted 1 changesets
$ mkcommit B0
$ hg log -G --hidden
@ f40ded968333 (draft): B0
|
o f6082bc4ffef (draft): A1
|
| x 8aaa48160adc (draft): A0
|/
o 1e4be0697311 (public): root
Actual testing
--------------
$ hg push
pushing to $TESTTMP/A4/server
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files (+1 heads)
1 new obsolescence markers
obsoleted 1 changesets
$ cd ../../