view tests/test-push-checkheads-pruned-B7.t @ 37291:b0041036214e

wireproto: define frame to represent progress updates

Today, a long-running operation on a server may run without any sign
of progress on the client. This can lead to the conclusion that the
server has hung or the connection has dropped. In fact, connections
can and do time out due to inactivity. And a long-running server
operation can result in the connection dropping prematurely because
no data is being sent!

While we're inventing the new wire protocol, let's provide a mechanism
for communicating progress on potentially expensive server-side events.

We introduce a new frame type that conveys "progress" updates. This
frame type essentially holds the data required to formulate a
``ui.progress()`` call.

We only define the frame right now. Implementing it will be a bit of
work since there is no analog to progress frames in the existing
wire protocol. We'll need to teach the ui object to write to the
wire protocol, etc.

The use of a CBOR map may seem wasteful, as this will encode key
names in every frame. This *is* wasteful. However, maps are
extensible. And the intent is to always use compression via
streams. Compression will make the overhead negligible since repeated
strings will be mostly eliminated over the wire.

Differential Revision: https://phab.mercurial-scm.org/D2902

====================================
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 ../..