view contrib/all-revsets.txt @ 32697:19b9fc40cc51

revlog: skeleton support for version 2 revlogs

There are a number of improvements we want to make to revlogs
that will require a new version - version 2. It is unclear what the
full set of improvements will be or when we'll be done with them.
What I do know is that the process will likely take longer than a
single release, will require input from various stakeholders to
evaluate changes, and will have many contentious debates and
bikeshedding.

It is unrealistic to develop revlog version 2 up front: there
are just too many uncertainties that we won't know until things
are implemented and experiments are run. Some changes will also
be invasive and prone to bit rot, so sitting on dozens of patches
is not practical.

This commit introduces skeleton support for version 2 revlogs in
a way that is flexible and not bound by backwards compatibility
concerns.

An experimental repo requirement for denoting revlog v2 has been
added. The requirement string has a sub-version component to it.
This will allow us to declare multiple requirements in the course
of developing revlog v2. Whenever we change the in-development
revlog v2 format, we can tweak the string, creating a new
requirement and locking out old clients. This will allow us to
make as many backwards incompatible changes and experiments to
revlog v2 as we want. In other words, we can land code and make
meaningful progress towards revlog v2 while still maintaining
extreme format flexibility up until the point we freeze the
format and remove the experimental labels.

To enable the new repo requirement, you must supply an experimental
and undocumented config option. But not just any boolean flag
will do: you need to explicitly use a value that no sane person
should ever type. This is an additional guard against enabling
revlog v2 on an installation it shouldn't be enabled on. The
specific scenario I'm trying to prevent is say a user with a
4.4 client with a frozen format enabling the option but then
downgrading to 4.3 and accidentally creating repos with an
outdated and unsupported repo format. Requiring a "challenge"
string should prevent this.

Because the format is not yet finalized and I don't want to take
any chances, revlog v2's version is currently 0xDEAD. I figure
squatting on a value we're likely never to use as an actual revlog
version to mean "internal testing only" is acceptable. And
"dead" is easily recognized as something meaningful.

There is a bunch of cleanup that is needed before work on revlog
v2 begins in earnest. I plan on doing that work once this patch
is accepted and we're comfortable with the idea of starting down
this path.

# All revsets ever used with revsetbenchmarks.py script
#
# The goal of this file is to gather all revsets ever used for benchmarking
# revset's performance. It should be used to gather revsets that test a
# specific usecase or a specific implementation of revset predicates.
# If you are working on the smartset implementation itself, check
# 'base-revsets.txt'.
#
# Please update this file with any revsets you use for benchmarking a change so
# that future contributors can easily find and retest it when doing further
# modification. Feel free to highlight interesting variants if needed.


## Revset from this section are all extracted from changelog when this file was
# created. Feel free to dig and improve documentation.

# Used in revision da05fe01170b
(20000::) - (20000)
# Used in revision 95af98616aa7
parents(20000)
# Used in revision 186fd06283b4
(_intlist('20000\x0020001')) and merge()
# Used in revision 911f5a6579d1
p1(20000)
p2(10000)
# Used in revision b6dc3b79bb25
0::
# Used in revision faf4f63533ff
bookmark()
# Used in revision 22ba2c0825da
tip~25
# Used in revision 0cf46b8298fe
bisect(range)
# Used in revision 5b65429721d5
divergent()
# Used in revision 6261b9c549a2
file(COPYING)
# Used in revision 44f471102f3a
follow(COPYING)
# Used in revision 8040a44aab1c
origin(tip)
# Used in revision bbf4f3dfd700
rev(25)
# Used in revision a428db9ab61d
p1()
# Used in revision c1546d7400ef
min(0::)
# Used in revision 546fa6576815
author(lmoscovicz) or author(mpm)
author(mpm) or author(lmoscovicz)
# Used in revision 9bfe68357c01
public() and id("d82e2223f132")
# Used in revision ba89f7b542c9
rev(25)
# Used in revision eb763217152a
rev(210000)
# Used in revision 69524a05a7fa
10:100
parents(10):parents(100)
# Used in revision 6f1b8b3f12fd
100~5
parents(100)~5
(100~5)~5
# Used in revision 7a42e5d4c418
children(tip~100)
# Used in revision 7e8737e6ab08
100^1
parents(100)^1
(100^1)^1
# Used in revision 30e0dcd7c5ff
matching(100)
matching(parents(100))
# Used in revision aafeaba22826
0|1|2|3|4|5|6|7|8|9
# Used in revision 33c7a94d4dd0
tip:0
# Used in revision 7d369fae098e
(0:100000)
# Used in revision b333ca94403d
0 + 1 + 2 + ... + 200
0 + 1 + 2 + ... + 1000
sort(0 + 1 + 2 + ... + 200)
sort(0 + 1 + 2 + ... + 1000)
# Used in revision 7fbef7932af9
first(0 + 1 + 2 + ... + 1000)
# Used in revision ceaf04bb14ff
0:1000
# Used in revision 262e6ad93885
not public()
(tip~1000::) - public()
not public() and branch("default")
# Used in revision 15412bba5a68
0::tip

## all the revsets from this section have been taken from the former central file
# for revset's benchmarking, they are undocumented for this reason.
all()
draft()
::tip
draft() and ::tip
::tip and draft()
author(lmoscovicz)
author(mpm)
::p1(p1(tip))::
public()
:10000 and public()
:10000 and draft()
(not public() - obsolete())

# The one below is used by rebase
(children(ancestor(tip~5, tip)) and ::(tip~5))::

# those two `roots(...)` inputs are close to what phase movement use.
roots((tip~100::) - (tip~100::tip))
roots((0::) - (0::tip))

# more roots testing
roots(tip~100:)
roots(:42)
roots(not public())
roots((0:tip)::)
roots(0::tip)
42:68 and roots(42:tip)
# Used in revision f140d6207cca
roots(0:tip)
# test disjoint set with multiple roots
roots((:42) + (tip~42:))

# Testing the behavior of "head()" in various situations
head()
head() - public()
draft() and head()
head() and author("mpm")

# testing the mutable phases set
draft()
secret()