tests/test-exchange-obsmarkers-case-A2.t

windows: add a method to convert Unix style command lines to Windows style

This started as a copy/paste of `os.path.expandvars()`, but limited to a given
dictionary of variables, converting `foo = foo + bar` to `foo += bar`, and
adding 'b' string prefixes.  Then code was added to make sure that a value being
substituted in wouldn't itself be expanded by cmd.exe.  But that left
inconsistent results between `$var1` and `%var1%` when its value was '%foo%'-
since neither were touched, `$var1` wouldn't expand but `%var1%` would.  So
instead, this just converts the Unix style to Windows style (if the variable
exists, because Windows will leave `%missing%` as-is), and lets cmd.exe do its
thing.

I then dropped the %% -> % conversion (because Windows doesn't do this), and
added the ability to escape the '$' with '\'.  The escape character is dropped,
for consistency with shell handling.

After everything seemed stable and working, running the whole test suite flagged
a problem near the end of test-bookmarks.t:1069.  The problem is cmd.exe won't
pass empty variables to its child, so defined but empty variables are now
skipped.  I can't think of anything better, and it seems like a pre-existing
violation of the documentation, which calls out that HG_OLDNODE is empty on
bookmark creation.

Future additions could potentially be replacing strong quotes with double quotes
(cmd.exe doesn't know what to do with the former), escaping a double quote, and
some tilde expansion via os.path.expanduser().  I've got some doubts about
replacing the strong quotes in case sh.exe is run, but it seems like the right
thing to do the vast majority of the time.  The original form of this was
discussed about a year ago[1].

[1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-July/100735.html

============================================
Testing obsolescence markers push: Cases A.2
============================================

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 A: simple cases
TestCase 2: Two heads, only one of them pushed

A.2 Two heads, only on of then pushed
=====================================

.. {{{
..     ⇠○ B
..   ⇠◔ | A
..    |/
..    ● O
.. }}}
..
.. Markers exist from:
..
..  * A
..  * B
..
..
.. Command runs:
..
..  * hg push -r A
..
.. Expected exchange:
..
..  * chain from A
..
.. Expected Exclude:
..
..  * chain from B

Setup
-----

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

initial

  $ setuprepos A.2
  creating test repo for test case A.2
  - pulldest
  - main
  - pushdest
  cd into `main` and proceed with env setup
  $ cd main
  $ mkcommit A
  $ hg debugobsolete aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa `getid 'desc(A)'`
  $ hg up '.~1'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mkcommit B
  created new head
  $ hg debugobsolete bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb `getid 'desc(B)'`
  $ hg log -G
  @  35b183996678 (draft): B
  |
  | o  f5bc6836db60 (draft): A
  |/
  o  a9bdc8b26820 (public): O
  
  $ inspect_obsmarkers
  obsstore content
  ================
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  $ cd ..
  $ cd ..

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

  $ dotest A.2 A
  ## Running testcase A.2
  # testing echange of "A" (f5bc6836db60)
  ## initial state
  # obstore: main
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  # obstore: pulldest
  ## pushing "A" from main to pushdest
  pushing to pushdest
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files
  remote: 1 new obsolescence markers
  ## post push state
  # obstore: main
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  ## pulling "f5bc6836db60" from main into pulldest
  pulling from main
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  1 new obsolescence markers
  new changesets f5bc6836db60
  (run 'hg update' to get a working copy)
  ## post pull state
  # obstore: main
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pushdest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
  # obstore: pulldest
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}

  $ cd ..