tests/test-addremove.t

commandserver: add new forking server implemented without using SocketServer

SocketServer.ForkingMixIn of Python 2.x has a couple of issues, such as:

 - race condition that leads to 100% CPU usage (Python 2.6)
   https://bugs.python.org/issue21491
 - can't wait for children belonging to different process groups (Python 2.6)
 - leaves at least one zombie process (Python 2.6, 2.7)
   https://bugs.python.org/issue11109

The first two are critical because we do setpgid(0, 0) in child process to
isolate terminal signals. The last one isn't, but ForkingMixIn seems to be
doing silly. So there are two choices:

 a) backport and maintain SocketServer until we can drop support for Python 2.x
 b) replace SocketServer by simpler one and eliminate glue codes

I chose (b) because it's great time for getting rid of utterly complicated
SocketServer stuff, and preparing for future move towards prefork service.

New unixforkingservice is implemented loosely based on chg 531f8ef64be6. It
is monolithic but much simpler than SocketServer. unixservicehandler provides
customizing points for chg, and it will be shared with future prefork service.

Old unixservice class is still used by chgserver. It will be removed later.

Thanks to Jun Wu for investigating these issues.

  $ hg init rep
  $ cd rep
  $ mkdir dir
  $ touch foo dir/bar
  $ hg -v addremove
  adding dir/bar
  adding foo
  $ hg -v commit -m "add 1"
  committing files:
  dir/bar
  foo
  committing manifest
  committing changelog
  committed changeset 0:6f7f953567a2
  $ cd dir/
  $ touch ../foo_2 bar_2
  $ hg -v addremove
  adding dir/bar_2
  adding foo_2
  $ hg -v commit -m "add 2"
  committing files:
  dir/bar_2
  foo_2
  committing manifest
  committing changelog
  committed changeset 1:e65414bf35c5
  $ cd ..
  $ hg forget foo
  $ hg -v addremove
  adding foo
  $ hg forget foo
#if windows
  $ hg -v addremove nonexistent
  nonexistent: The system cannot find the file specified
  [1]
#else
  $ hg -v addremove nonexistent
  nonexistent: No such file or directory
  [1]
#endif
  $ cd ..

  $ hg init subdir
  $ cd subdir
  $ mkdir dir
  $ cd dir
  $ touch a.py
  $ hg addremove 'glob:*.py'
  adding a.py
  $ hg forget a.py
  $ hg addremove -I 'glob:*.py'
  adding a.py
  $ hg forget a.py
  $ hg addremove
  adding dir/a.py
  $ cd ..

  $ hg init sim
  $ cd sim
  $ echo a > a
  $ echo a >> a
  $ echo a >> a
  $ echo c > c
  $ hg commit -Ama
  adding a
  adding c
  $ mv a b
  $ rm c
  $ echo d > d
  $ hg addremove -n -s 50 # issue 1696
  removing a
  adding b
  removing c
  adding d
  recording removal of a as rename to b (100% similar)
  $ hg addremove -s 50
  removing a
  adding b
  removing c
  adding d
  recording removal of a as rename to b (100% similar)
  $ hg commit -mb
  $ cp b c
  $ hg forget b
  $ hg addremove -s 50
  adding b
  adding c

  $ rm c
#if windows
  $ hg ci -A -m "c" nonexistent
  nonexistent: The system cannot find the file specified
  abort: failed to mark all new/missing files as added/removed
  [255]
#else
  $ hg ci -A -m "c" nonexistent
  nonexistent: No such file or directory
  abort: failed to mark all new/missing files as added/removed
  [255]
#endif
  $ hg st
  ! c
  $ cd ..