view tests/test-push-checkheads-pruned-B7.t @ 40176:41263df08109

wireprotov2: change how revisions are specified to changesetdata

Right now, we have a handful of arguments for specifying the revisions
whose data should be returned. Defining how all these arguments
interact when various combinations are present is difficult.

This commit establishes a new, generic mechanism for specifying
revisions. Instead of a hodgepodge of arguments defining things, we
have a list of dicts that specify revision selectors. The final set
of revisions is a union of all these selectors.

We implement support for specifying revisions based on:

* An explicit list of changeset revisions
* An explicit list of changeset revisions plus ancestry depth
* A DAG range between changeset roots and heads

If you squint hard enough, this problem has already been solved by
revsets. But I'm reluctant to expose revsets to the wire protocol
because that would require servers to implement a revset parser.
Plus there are security and performance implications: the set
of revision selectors needs to be narrowly and specifically tailored
for what is appropriate to be executing on a server. Perhaps there
would be a way for us to express the "parse tree" of a revset
query, for example. I'm not sure. We can explore this space another
time. For now, the new mechanism should bring sufficient flexibility
while remaining relatively simple.

The selector "types" are prefixed with "changeset" because I plan
to add manifest and file-flavored selectors as well. This will enable
us to e.g. select file revisions based on a range of changeset
revisions.

Differential Revision: https://phab.mercurial-scm.org/D4979

====================================
Testing head checking code: Case B-7
====================================

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 B: simple case involving pruned changesets
TestCase 7: single changesets, pruned then superseeded (on an existing changeset)

.. old-state:
..
.. * 1 changeset branch
..
.. new-state:
..
.. * old branch is rewritten onto the common set,
.. * the new version is then pruned.
..
.. expected-result:
..
.. * push allowed
..
.. graph-summary:
..
..   A ø⇠⊗ A'
.. B ◔ | |
..    \|/
..     ●

  $ . $TESTDIR/testlib/push-checkheads-util.sh

Test setup
----------

  $ mkdir B7
  $ cd B7
  $ 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 B0
  created new head
  $ mkcommit A1
  $ hg up 'desc(B0)'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg debugobsolete `getid "desc(A0)"` `getid "desc(A1)"`
  obsoleted 1 changesets
  $ hg debugobsolete --record-parents `getid "desc(A1)"`
  obsoleted 1 changesets
  $ hg log -G --hidden
  x  ba93660aff8d (draft): A1
  |
  @  74ff5441d343 (draft): B0
  |
  | x  8aaa48160adc (draft): A0
  |/
  o  1e4be0697311 (public): root
  

Actual testing
--------------

  $ hg push
  pushing to $TESTTMP/B7/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  2 new obsolescence markers
  obsoleted 1 changesets

  $ cd ../..