tests/test-merge-subrepos.t

wireprotoserver: ability to run an SSH server until an event is set

It seems useful to be able to start an SSH protocol server that
won't run forever and won't call sys.exit() when it stops. This
could be used to facilitate intra-process testing of the SSH
protocol, for example.

We teach the server function to loop until a threading.Event is set
and invent a new API to run the server until an event is set. It also
won't sys.exit() afterwards.

There aren't many callers of serve_forever(). So we could refactor
them relatively easily. But I was lazy.

threading.Event might be a bit heavyweight. An alternative would be
a list whose only elements is changed. We can't use a simple scalar
value like a bool or int because those types are immutable. Events
are what you use in systems programming for this use case, so the
use of threading.Event seems justified.

Differential Revision: https://phab.mercurial-scm.org/D2461

  $ hg init

  $ echo a > a
  $ hg ci -qAm 'add a'

  $ hg init subrepo
  $ echo 'subrepo = http://example.net/libfoo' > .hgsub
  $ hg ci -qAm 'added subrepo'

  $ hg up -qC 0
  $ echo ax > a
  $ hg ci -m 'changed a'
  created new head

  $ hg up -qC 1
  $ cd subrepo
  $ echo b > b
  $ hg add b
  $ cd ..

Should fail, since there are added files to subrepo:

  $ hg merge
  abort: uncommitted changes in subrepository "subrepo"
  [255]

Deleted files trigger a '+' marker in top level repos.  Deleted files are also
noticed by `update --check` in the top level repo.

  $ hg ci -Sqm 'add b'
  $ echo change > subrepo/b

  $ hg ci -Sm 'change b'
  committing subrepository subrepo

  $ rm a
  $ hg id
  9bfe45a197d7+ tip
  $ hg sum
  parent: 4:9bfe45a197d7 tip
   change b
  branch: default
  commit: 1 deleted (clean)
  update: 1 new changesets, 2 branch heads (merge)
  phases: 5 draft

  $ hg up --check -r '.^'
  abort: uncommitted changes
  [255]
  $ hg st -S
  ! a
  $ hg up -Cq .

Test that dirty is consistent through subrepos

  $ rm subrepo/b

A deleted subrepo file is flagged as dirty, like the top level repo

  $ hg id --config extensions.blackbox= --config blackbox.dirty=True
  9bfe45a197d7+ tip
  $ cat .hg/blackbox.log
  * @9bfe45a197d7b0ab09bf287729dd57e9619c9da5+ (*)> serve --cmdserver chgunix * (glob) (chg !)
  * @9bfe45a197d7b0ab09bf287729dd57e9619c9da5+ (*)> id --config *extensions.blackbox=* --config *blackbox.dirty=True* (glob)
  * @9bfe45a197d7b0ab09bf287729dd57e9619c9da5+ (*)> id --config *extensions.blackbox=* --config *blackbox.dirty=True* exited 0 * (glob)

TODO: a deleted file should be listed as such, like the top level repo

  $ hg sum
  parent: 4:9bfe45a197d7 tip
   change b
  branch: default
  commit: (clean)
  update: 1 new changesets, 2 branch heads (merge)
  phases: 5 draft

Modified subrepo files are noticed by `update --check` and `summary`

  $ echo mod > subrepo/b
  $ hg st -S
  M subrepo/b

  $ hg up -r '.^' --check
  abort: uncommitted changes in subrepository "subrepo"
  [255]

  $ hg sum
  parent: 4:9bfe45a197d7 tip
   change b
  branch: default
  commit: 1 subrepos
  update: 1 new changesets, 2 branch heads (merge)
  phases: 5 draft

TODO: why is -R needed here?  If it's because the subrepo is treated as a
discrete unit, then this should probably warn or something.
  $ hg revert -R subrepo --no-backup subrepo/b -r .

  $ rm subrepo/b
  $ hg st -S
  ! subrepo/b

`hg update --check` notices a subrepo with a missing file, like it notices a
missing file in the top level repo.

  $ hg up -r '.^' --check
  abort: uncommitted changes in subrepository "subrepo"
  [255]

  $ hg up -r '.^' --config ui.interactive=True << EOF
  > d
  > EOF
  other [destination] changed b which local [working copy] deleted
  use (c)hanged version, leave (d)eleted, or leave (u)nresolved? d
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

XXX: There's a difference between wdir() and '.', so there should be a status.
`hg files -S` from the top is also missing 'subrepo/b'.

  $ hg st -S
  $ hg st -R subrepo
  $ hg files -R subrepo
  [1]
  $ hg files -R subrepo -r '.'
  subrepo/b

  $ hg bookmark -r tip @other
  $ echo xyz > subrepo/c
  $ hg ci -SAm 'add c'
  adding subrepo/c
  committing subrepository subrepo
  created new head
  $ rm subrepo/c

Merge sees deleted subrepo files as an uncommitted change

  $ hg merge @other
  abort: uncommitted changes in subrepository "subrepo"
  [255]