tests/test-rebase-legacy.t

peer: introduce a limitedarguments attributes

When set to True, it signal that the peer cannot receive too larges arguments
and that algorithm must adapt. This should only be True for http peer that does
not support argument passed as "post".

This will be useful to unlock better discovery performance in the next
changesets.

I am using a dedicated argument because this is not really a usual
"capabilities" things. An alternative approach would be to adds a
"large-arguments" to all peer, but the http peers. That seemed a bit too hacky
to me.

Test rebase --continue with rebasestate written by legacy client

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > drawdag=$TESTDIR/drawdag.py
  > EOF

  $ hg init
  $ hg debugdrawdag <<'EOF'
  >    D H
  >    | |
  >    C G
  >    | |
  >    B F
  >    | |
  >  Z A E
  >   \|/
  >    R
  > EOF

rebasestate generated by a legacy client running "hg rebase -r B+D+E+G+H -d Z"

  $ touch .hg/last-message.txt
  $ cat > .hg/rebasestate <<EOF
  > 0000000000000000000000000000000000000000
  > f424eb6a8c01c4a0c0fba9f863f79b3eb5b4b69f
  > 0000000000000000000000000000000000000000
  > 0
  > 0
  > 0
  > 
  > 21a6c45028857f500f56ae84fbf40689c429305b:-2
  > de008c61a447fcfd93f808ef527d933a84048ce7:0000000000000000000000000000000000000000
  > c1e6b162678d07d0b204e5c8267d51b4e03b633c:0000000000000000000000000000000000000000
  > aeba276fcb7df8e10153a07ee728d5540693f5aa:-3
  > bd5548558fcf354d37613005737a143871bf3723:-3
  > d2fa1c02b2401b0e32867f26cce50818a4bd796a:0000000000000000000000000000000000000000
  > 6f7a236de6852570cd54649ab62b1012bb78abc8:0000000000000000000000000000000000000000
  > 6582e6951a9c48c236f746f186378e36f59f4928:0000000000000000000000000000000000000000
  > EOF

  $ hg rebase --continue
  rebasing 4:c1e6b162678d "B" (B)
  rebasing 8:6f7a236de685 "D" (D)
  rebasing 2:de008c61a447 "E" (E)
  rebasing 7:d2fa1c02b240 "G" (G)
  rebasing 9:6582e6951a9c "H" (H tip)
  warning: orphaned descendants detected, not stripping c1e6b162678d, de008c61a447
  saved backup bundle to $TESTTMP/.hg/strip-backup/6f7a236de685-9880a3dc-rebase.hg

  $ hg log -G -T '{rev}:{node|short} {desc}\n'
  o  11:721b8da0a708 H
  |
  o  10:9d65695ec3c2 G
  |
  o  9:21c8397a5d68 E
  |
  | o  8:fc52970345e8 D
  | |
  | o  7:eac96551b107 B
  |/
  | o  6:bd5548558fcf C
  | |
  | | o  5:aeba276fcb7d F
  | | |
  | o |  4:c1e6b162678d B
  | | |
  o | |  3:f424eb6a8c01 Z
  | | |
  +---o  2:de008c61a447 E
  | |
  | o  1:21a6c4502885 A
  |/
  o  0:b41ce7760717 R