tests/test-issue4074.t

commands: rename clone --uncompressed to --stream and document

--uncompressed isn't a very good name and its description in the
help documentation isn't very useful. We refer to this concept as
"stream clones" in a number of places. I think it makes sense to
change the user-facing argument to use the mode --stream. So this
commit does that.

We keep --uncompressed around for backwards compatibility.

While we're here, we overhaul the help docs for streaming clones
to be somewhat useful.

All tests have been updated to reflect the new preferred --stream
argument. A test for backwards compatibility of --uncompressed has
been added.

.. bc::

   `hg clone --stream` should now be used instead of --uncompressed.

   --uncompressed is marked as deprecated and is an alias for --stream.
   There is no schedule for elimination of --uncompressed.

Differential Revision: https://phab.mercurial-scm.org/D864

#require no-pure

A script to generate nasty diff worst-case scenarios:

  $ cat > s.py <<EOF
  > import random
  > for x in xrange(100000):
  >     print
  >     if random.randint(0, 100) >= 50:
  >         x += 1
  >     print(hex(x))
  > EOF

  $ hg init a
  $ cd a

Check in a big file:

  $ $PYTHON ../s.py > a
  $ hg ci -qAm0

Modify it:

  $ $PYTHON ../s.py > a

Time a check-in, should never take more than 10 seconds user time:

  $ hg ci --time -m1
  time: real .* secs .user [0-9][.].* sys .* (re)