branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
============================================================================
Pulling from modern to a non-general delta target (and other related checks)
============================================================================
There is various issue that can arise when we update the code with modern
storage in mind while working on delta processing. So this file is meant for
various scenario that might break in the future or have break in the past.
Setup
=====
Create a modern server with an older clone
$ cat << EOF >> $HGRCPATH
> [command-templates]
> log = "{desc} {tags}\n"
> EOF
$ hg init server
$ hg clone --quiet --pull server client --config format.usegeneraldelta=no
$ hg debugformat -R client | grep generaldelta
generaldelta: no
Create some complexe history
$ cd server
$ hg debugbuilddag -n '.+3:a$.+5:b/a:k$.+7:c/b:l$.+6:d/a:m<k+6/l+1/m'
$ hg log -G
o r36 tip
|\
| o r35
| |
| o r34
| |\
| | o r33
| | |
| | o r32
| | |
| | o r31
| | |
| | o r30
| | |
| | o r29
| | |
| | o r28
| | |
o | | r27 m
|\ \ \
| o | | r26 d
| | | |
| o | | r25
| | | |
| o | | r24
| | | |
| o | | r23
| | | |
| o | | r22
| | | |
| o | | r21
| | | |
| o | | r20
| / /
| o | r19 l
| |\ \
| | o | r18 c
| | | |
| | o | r17
| | | |
| | o | r16
| | | |
| | o | r15
| | | |
| | o | r14
| | | |
| | o | r13
| | | |
| | o | r12
| | | |
| | o | r11
| | /
+---o r10 k
| |/
| o r9 b
| |
| o r8
| |
| o r7
| |
| o r6
| |
| o r5
| |
| o r4
|
o r3 a
|
o r2
|
o r1
|
o r0
$ cd ..
Pull it in the client
=====================
pull with default value
-----------------------
$ cp -R client client-simple-pull
$ hg -R client-simple-pull pull
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 37 changesets with 37 changes to 37 files
new changesets 61246295ee1e:b4b117cbbcf3
(run 'hg update' to get a working copy)
$ hg -R client-simple-pull verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checking dirstate
checked 37 changesets with 37 changes to 37 files
pull with "no-reuse" policy
---------------------------
$ cp -R client client-no-reuse
$ hg -R client-no-reuse pull --config paths.default:pulled-delta-reuse-policy=no-reuse
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 37 changesets with 37 changes to 37 files
new changesets 61246295ee1e:b4b117cbbcf3
(run 'hg update' to get a working copy)
$ hg -R client-no-reuse verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checking dirstate
checked 37 changesets with 37 changes to 37 files
pull with "try-base" policy
---------------------------
$ cp -R client client-try-base
$ hg -R client-try-base pull --config paths.default:pulled-delta-reuse-policy=try-base
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 37 changesets with 37 changes to 37 files
new changesets 61246295ee1e:b4b117cbbcf3
(run 'hg update' to get a working copy)
$ hg -R client-try-base verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checking dirstate
checked 37 changesets with 37 changes to 37 files
pull with "forced" policy
-------------------------
$ cp -R client client-forced
$ hg -R client-forced paths --config paths.default:pulled-delta-reuse-policy=forced
default = $TESTTMP/server
default:pulled-delta-reuse-policy = forced
$ hg -R client-forced pull --config paths.default:pulled-delta-reuse-policy=forced
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 37 changesets with 37 changes to 37 files
new changesets 61246295ee1e:b4b117cbbcf3
(run 'hg update' to get a working copy)
$ hg -R client-forced verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checking dirstate
checked 37 changesets with 37 changes to 37 files