view tests/test-exchange-obsmarkers-case-D3.t @ 42377:0546ead39a7e stable

manifest: avoid corruption by dropping removed files with pure (issue5801)

Previously, removed files would simply be marked by overwriting the first byte
with NUL and dropping their entry in `self.position`.  But no effort was made to
ignore them when compacting the dictionary into text form.  This allowed them to
slip into the manifest revision, since the code seems to be trying to minimize
the string operations by copying as large a chunk as possible.  As part of this,
compact() walks the existing text based on entries in the `positions` list, and
consumed everything up to the next position entry.   This typically resulted in
a ValueError complaining about unsorted manifest entries.

Sometimes it seems that files do get dropped in large repos- it seems to
correspond to there being a new entry that would take the same slot.  A much
more trivial problem is that if the only changes were removals, `_compact()`
didn't even run because `__delitem__` doesn't add anything to `self.extradata`.
Now there's an explicit variable to flag this, both to allow `_compact()` to
run, and to avoid searching the manifest in cases where there are no removals.

In practice, this behavior was mostly obscured by the check in fastdelta() which
takes a different path that explicitly drops removed files if there are fewer
than 1000 changes.  However, timeless has a repo where after rebasing tens of
commits, a totally different path[1] is taken that bypasses the change count
check and hits this problem.

[1] https://www.mercurial-scm.org/repo/hg/file/2338bdea4474/mercurial/manifest.py#l1511

============================================
Testing obsolescence markers push: Cases D.3
============================================

Mercurial pushes obsolescences markers relevant to the "pushed-set", the set of
all changesets that requested to be "in sync" after the push (even if they are
already on both side).

This test belongs to a series of tests checking such set is properly computed
and applied. This does not tests "obsmarkers" discovery capabilities.

Category D: Partial Information Case
TestCase 3: missing prune target (prune not in "pushed set")

D.3 missing prune target (prune not in "pushed set")
====================================================

.. {{{
..  A ø⇠✕ A'
..     | |
..     | ○ B
..     |/
..     ● O
.. }}}
..
.. Marker exist from:
..
..  * `A ø⇠o A'`
..  * A' (prune)
..
.. Command runs:
..
..  * hg push
..
.. Expected exclude:
..
..  * `A ø⇠o A'`
..  * A' (prune)

Setup
-----

  $ . $TESTDIR/testlib/exchange-obsmarker-util.sh

initial

  $ setuprepos D.3
  creating test repo for test case D.3
  - pulldest
  - main
  - pushdest
  cd into `main` and proceed with env setup
  $ cd main
  $ mkcommit A0
  $ hg up -q 0
  $ mkcommit B
  created new head
  $ mkcommit A1
  $ hg debugobsolete `getid 'desc(A0)'` `getid 'desc(A1)'`
  obsoleted 1 changesets
  $ hg prune -d '0 0' .
  obsoleted 1 changesets
  $ hg strip --hidden -q 'desc(A1)'
  $ hg log -G --hidden
  @  35b183996678 (draft): B
  |
  | x  28b51eb45704 (draft): A0
  |/
  o  a9bdc8b26820 (public): O
  
  $ inspect_obsmarkers
  obsstore content
  ================
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f 6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  $ cd ..
  $ cd ..

Actual Test
-----------

  $ dotest D.3 O
  ## Running testcase D.3
  # testing echange of "O" (a9bdc8b26820)
  ## initial state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f 6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest
  ## pushing "O" from main to pushdest
  pushing to pushdest
  searching for changes
  no changes found
  ## post push state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f 6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest
  ## pulling "a9bdc8b26820" from main into pulldest
  pulling from main
  no changes found
  ## post pull state
  # obstore: main
  28b51eb45704506b5c603decd6bf7ac5e0f6a52f 6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  6aa67a7b4baa6fb41b06aed38d5b1201436546e2 0 {35b1839966785d5703a01607229eea932db42f87} (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest