view tests/test-wireproto-command-filesdata.t @ 42743:8c9a6adec67a

rust-discovery: using the children cache in add_missing

The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.

The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.

This is a case where staying on the same side of the interface
between the two languages has clear benefits.

On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.

For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:

Rust version with simple iteration
  addcommons: 57.287us
  first undecided computation: 184.278334ms
  first children cache computation: 131.056us
  addmissings iteration: 42.766us
  first addinfo total: 185.24 ms

Python + C version
  first addcommons: 0.29 ms
  addcommons 0.21 ms
  first undecided computation 191.35 ms
  addmissings 45.75 ms
  first addinfo total: 237.77 ms

On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:

Rust version:
  first undecided computation: 293.842629ms
  first children cache computation: 407.911297ms
  addmissings iteration: 34.312869ms
  first addinfo total: 776.02 ms
  taking initial sample
  query 2: sampling time: 1318.38 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings: 143.062us

Python + C version:
  first undecided computation 298.13 ms
  addmissings 80.13 ms
  first addinfo total: 399.62 ms
  taking initial sample
  query 2: sampling time: 3957.23 ms
  query 2; still undecided: 1005013, sample size is: 200
  addmissings 52.88 ms

Differential Revision: https://phab.mercurial-scm.org/D6428

  $ . $TESTDIR/wireprotohelpers.sh

  $ hg init server
  $ enablehttpv2 server
  $ cd server
  $ cat > a << EOF
  > a0
  > 00000000000000000000000000000000000000
  > 11111111111111111111111111111111111111
  > EOF
  $ cat > b << EOF
  > b0
  > aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
  > bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
  > EOF
  $ mkdir -p dir0/child0 dir0/child1 dir1
  $ echo c0 > dir0/c
  $ echo d0 > dir0/d
  $ echo e0 > dir0/child0/e
  $ echo f0 > dir0/child1/f
  $ hg -q commit -A -m 'commit 0'

  $ echo a1 >> a
  $ echo d1 > dir0/d
  $ echo g0 > g
  $ echo h0 > h
  $ hg -q commit -A -m 'commit 1'
  $ echo f1 > dir0/child1/f
  $ echo i0 > dir0/i
  $ hg -q commit -A -m 'commit 2'

  $ hg -q up -r 0
  $ echo a2 >> a
  $ hg commit -m 'commit 3'
  created new head

Create multiple heads introducing the same file nodefile node

  $ hg -q up -r 0
  $ echo foo > dupe-file
  $ hg commit -Am 'dupe 1'
  adding dupe-file
  created new head
  $ hg -q up -r 0
  $ echo foo > dupe-file
  $ hg commit -Am 'dupe 2'
  adding dupe-file
  created new head

  $ hg log -G -T '{rev}:{node} {desc}\n'
  @  5:47fc30580911232cb264675b402819deddf6c6f0 dupe 2
  |
  | o  4:b16cce2967c1749ef4f4e3086a806cfbad8a3af7 dupe 1
  |/
  | o  3:476fbf122cd82f6726f0191ff146f67140946abc commit 3
  |/
  | o  2:b91c03cbba3519ab149b6cd0a0afbdb5cf1b5c8a commit 2
  | |
  | o  1:5b0b1a23577e205ea240e39c9704e28d7697cbd8 commit 1
  |/
  o  0:6e875ff18c227659ad6143bb3580c65700734884 commit 0
  

  $ hg serve -p $HGPORT -d --pid-file hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

Missing arguments is an error

  $ sendhttpv2peer << EOF
  > command filesdata
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  abort: missing required arguments: revisions!
  [255]

Bad pattern to pathfilter is rejected

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >          b'type': b'changesetexplicit',
  >          b'nodes': [
  >              b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >          ]}]
  >     pathfilter eval:{b'include': [b'bad:foo']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  abort: include pattern must begin with `path:` or `rootfilesin:`; got bad:foo!
  [255]

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     pathfilter eval:{b'exclude': [b'glob:foo']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  abort: exclude pattern must begin with `path:` or `rootfilesin:`; got glob:foo!
  [255]

Fetching a single changeset without parents fetches all files

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 8,
      b'totalpaths': 8
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 1
    },
    {
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

Fetching a single changeset saying parents data is available fetches just new files

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     haveparents eval:True
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 4,
      b'totalpaths': 4
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

A path filter for a sub-directory is honored

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     haveparents eval:True
  >     pathfilter eval:{b'include': [b'path:dir0']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 1,
      b'totalpaths': 1
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    }
  ]

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     haveparents eval:True
  >     pathfilter eval:{b'exclude': [b'path:a', b'path:g']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 2,
      b'totalpaths': 2
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

Requesting multiple changeset nodes without haveparents sends all data for both

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >             b'\xb9\x1c\x03\xcb\xba\x35\x19\xab\x14\x9b\x6c\xd0\xa0\xaf\xbd\xb5\xcf\x1b\x5c\x8a',
  >         ]}]
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 10,
      b'totalpaths': 9
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 2
    },
    {
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    {
      b'node': b'(\xc7v\xae\x08\xd0\xd5^\xb4\x06H\xb4\x01\xb9\x0f\xf5DH4\x8e'
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'dir0/i',
      b'totalitems': 1
    },
    {
      b'node': b'\xd7t\xb5\x80Jq\xfd1\xe1\xae\x05\xea\x8e2\xdd\x9b\xa3\xd8S\xd7'
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

Requesting multiple changeset nodes with haveparents sends incremental data for both

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >             b'\xb9\x1c\x03\xcb\xba\x35\x19\xab\x14\x9b\x6c\xd0\xa0\xaf\xbd\xb5\xcf\x1b\x5c\x8a',
  >         ]}]
  >     haveparents eval:True
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 6,
      b'totalpaths': 6
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 1
    },
    {
      b'node': b'(\xc7v\xae\x08\xd0\xd5^\xb4\x06H\xb4\x01\xb9\x0f\xf5DH4\x8e'
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'dir0/i',
      b'totalitems': 1
    },
    {
      b'node': b'\xd7t\xb5\x80Jq\xfd1\xe1\xae\x05\xea\x8e2\xdd\x9b\xa3\xd8S\xd7'
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

Requesting parents works

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     fields eval:[b'parents']
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 8,
      b'totalpaths': 8
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11',
      b'parents': [
        b'd\x9d\x14\x9d\xf4=\x83\x88%#\xb7\xfb\x1ej:\xf6\xf1\x90{9',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 1
    },
    {
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G',
      b'parents': [
        b'S\x82\x06\xdc\x97\x1eR\x15@\xd6\x84:\xbf\xe6\xd1`2\xf6\xd4&',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K',
      b'parents': [
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    }
  ]

Requesting revision data works
(haveparents defaults to False, so fulltext is emitted)

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     fields eval:[b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 8,
      b'totalpaths': 8
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          84
        ]
      ],
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    b'a0\n00000000000000000000000000000000000000\n11111111111111111111111111111111111111\na1\n',
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          81
        ]
      ],
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    b'b0\naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\nbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\n',
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    b'c0\n',
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    b'e0\n',
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    b'f0\n',
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    b'd1\n',
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    b'g0\n',
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    },
    b'h0\n'
  ]

haveparents=False should be same as above

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     fields eval:[b'revision']
  >     haveparents eval:False
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 8,
      b'totalpaths': 8
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          84
        ]
      ],
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    b'a0\n00000000000000000000000000000000000000\n11111111111111111111111111111111111111\na1\n',
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          81
        ]
      ],
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    b'b0\naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\nbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\n',
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    b'c0\n',
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    b'e0\n',
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    b'f0\n',
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    b'd1\n',
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    b'g0\n',
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    },
    b'h0\n'
  ]

haveparents=True should emit a delta

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >         ]}]
  >     fields eval:[b'revision']
  >     haveparents eval:True
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 4,
      b'totalpaths': 4
    },
    {
      b'path': b'a',
      b'totalitems': 1
    },
    {
      b'deltabasenode': b'd\x9d\x14\x9d\xf4=\x83\x88%#\xb7\xfb\x1ej:\xf6\xf1\x90{9',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    b'\x00\x00\x00Q\x00\x00\x00Q\x00\x00\x00\x03a1\n',
    {
      b'path': b'dir0/d',
      b'totalitems': 1
    },
    {
      b'deltabasenode': b'S\x82\x06\xdc\x97\x1eR\x15@\xd6\x84:\xbf\xe6\xd1`2\xf6\xd4&',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03d1\n',
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    b'g0\n',
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    },
    b'h0\n'
  ]

Requesting multiple revisions works
(first revision is a fulltext since haveparents=False by default)

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x6e\x87\x5f\xf1\x8c\x22\x76\x59\xad\x61\x43\xbb\x35\x80\xc6\x57\x00\x73\x48\x84',
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >             b'\xb9\x1c\x03\xcb\xba\x35\x19\xab\x14\x9b\x6c\xd0\xa0\xaf\xbd\xb5\xcf\x1b\x5c\x8a',
  >         ]}]
  >     fields eval:[b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 12,
      b'totalpaths': 9
    },
    {
      b'path': b'a',
      b'totalitems': 2
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          81
        ]
      ],
      b'node': b'd\x9d\x14\x9d\xf4=\x83\x88%#\xb7\xfb\x1ej:\xf6\xf1\x90{9'
    },
    b'a0\n00000000000000000000000000000000000000\n11111111111111111111111111111111111111\n',
    {
      b'deltabasenode': b'd\x9d\x14\x9d\xf4=\x83\x88%#\xb7\xfb\x1ej:\xf6\xf1\x90{9',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    b'\x00\x00\x00Q\x00\x00\x00Q\x00\x00\x00\x03a1\n',
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          81
        ]
      ],
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    b'b0\naaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\nbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\n',
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    b'c0\n',
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    b'e0\n',
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 2
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    b'f0\n',
    {
      b'deltabasenode': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'(\xc7v\xae\x08\xd0\xd5^\xb4\x06H\xb4\x01\xb9\x0f\xf5DH4\x8e'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03f1\n',
    {
      b'path': b'dir0/d',
      b'totalitems': 2
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'S\x82\x06\xdc\x97\x1eR\x15@\xd6\x84:\xbf\xe6\xd1`2\xf6\xd4&'
    },
    b'd0\n',
    {
      b'deltabasenode': b'S\x82\x06\xdc\x97\x1eR\x15@\xd6\x84:\xbf\xe6\xd1`2\xf6\xd4&',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03d1\n',
    {
      b'path': b'dir0/i',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xd7t\xb5\x80Jq\xfd1\xe1\xae\x05\xea\x8e2\xdd\x9b\xa3\xd8S\xd7'
    },
    b'i0\n',
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    b'g0\n',
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    },
    b'h0\n'
  ]

Requesting linknode field works

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x6e\x87\x5f\xf1\x8c\x22\x76\x59\xad\x61\x43\xbb\x35\x80\xc6\x57\x00\x73\x48\x84',
  >             b'\x5b\x0b\x1a\x23\x57\x7e\x20\x5e\xa2\x40\xe3\x9c\x97\x04\xe2\x8d\x76\x97\xcb\xd8',
  >             b'\xb9\x1c\x03\xcb\xba\x35\x19\xab\x14\x9b\x6c\xd0\xa0\xaf\xbd\xb5\xcf\x1b\x5c\x8a',
  >         ]}]
  >     fields eval:[b'linknode']
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 12,
      b'totalpaths': 9
    },
    {
      b'path': b'a',
      b'totalitems': 2
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'd\x9d\x14\x9d\xf4=\x83\x88%#\xb7\xfb\x1ej:\xf6\xf1\x90{9'
    },
    {
      b'linknode': b'[\x0b\x1a#W~ ^\xa2@\xe3\x9c\x97\x04\xe2\x8dv\x97\xcb\xd8',
      b'node': b'\n\x862\x1f\x13y\xd1\xa9\xec\xd0W\x9a"\x97z\xf7\xa5\xac\xaf\x11'
    },
    {
      b'path': b'b',
      b'totalitems': 1
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'\x88\xbac\xb8\xd8\xc6 :\xc6z\xc9\x98\xac\xd9\x17K\xf7\x05!\xb2'
    },
    {
      b'path': b'dir0/c',
      b'totalitems': 1
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'\x91DE4j\x0c\xa0b\x9b\xd4|\xeb]\xfe\x07\xe4\xd4\xcf%\x01'
    },
    {
      b'path': b'dir0/child0/e',
      b'totalitems': 1
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'\xbb\xbal\x06\xb3\x0fD=4\xff\x84\x1b\xc9\x85\xc4\xd0\x82|k\xe4'
    },
    {
      b'path': b'dir0/child1/f',
      b'totalitems': 2
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'\x12\xfc}\xcdw;Z\n\x92\x9c\xe1\x95"\x80\x83\xc6\xdd\xc9\xce\xc4'
    },
    {
      b'linknode': b'\xb9\x1c\x03\xcb\xba5\x19\xab\x14\x9bl\xd0\xa0\xaf\xbd\xb5\xcf\x1b\\\x8a',
      b'node': b'(\xc7v\xae\x08\xd0\xd5^\xb4\x06H\xb4\x01\xb9\x0f\xf5DH4\x8e'
    },
    {
      b'path': b'dir0/d',
      b'totalitems': 2
    },
    {
      b'linknode': b'n\x87_\xf1\x8c"vY\xadaC\xbb5\x80\xc6W\x00sH\x84',
      b'node': b'S\x82\x06\xdc\x97\x1eR\x15@\xd6\x84:\xbf\xe6\xd1`2\xf6\xd4&'
    },
    {
      b'linknode': b'[\x0b\x1a#W~ ^\xa2@\xe3\x9c\x97\x04\xe2\x8dv\x97\xcb\xd8',
      b'node': b'\x93\x88)\xad\x01R}2\xba\x06_\x81#6\xfe\xc7\x9d\xdd9G'
    },
    {
      b'path': b'dir0/i',
      b'totalitems': 1
    },
    {
      b'linknode': b'\xb9\x1c\x03\xcb\xba5\x19\xab\x14\x9bl\xd0\xa0\xaf\xbd\xb5\xcf\x1b\\\x8a',
      b'node': b'\xd7t\xb5\x80Jq\xfd1\xe1\xae\x05\xea\x8e2\xdd\x9b\xa3\xd8S\xd7'
    },
    {
      b'path': b'g',
      b'totalitems': 1
    },
    {
      b'linknode': b'[\x0b\x1a#W~ ^\xa2@\xe3\x9c\x97\x04\xe2\x8dv\x97\xcb\xd8',
      b'node': b'\xde\xca\xba5DFjI\x95r\xe9\x0f\xac\xe6\xfa\x0c!k\xba\x8c'
    },
    {
      b'path': b'h',
      b'totalitems': 1
    },
    {
      b'linknode': b'[\x0b\x1a#W~ ^\xa2@\xe3\x9c\x97\x04\xe2\x8dv\x97\xcb\xd8',
      b'node': b'\x03A\xfc\x84\x1b\xb5\xb4\xba\x93\xb2mM\xdaa\xf7y6]\xb3K'
    }
  ]

Test behavior where a file node is introduced in 2 DAG heads

Request for changeset introducing filenode returns linknode as self

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\xb1\x6c\xce\x29\x67\xc1\x74\x9e\xf4\xf4\xe3\x08\x6a\x80\x6c\xfb\xad\x8a\x3a\xf7',
  >         ]}]
  >     fields eval:[b'linknode']
  >     pathfilter eval:{b'include': [b'path:dupe-file']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 1,
      b'totalpaths': 1
    },
    {
      b'path': b'dupe-file',
      b'totalitems': 1
    },
    {
      b'linknode': b'\xb1l\xce)g\xc1t\x9e\xf4\xf4\xe3\x08j\x80l\xfb\xad\x8a:\xf7',
      b'node': b'.\xd2\xa3\x91*\x0b$P C\xea\xe8N\xe4\xb2y\xc1\x8b\x90\xdd'
    }
  ]

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\xb1\x6c\xce\x29\x67\xc1\x74\x9e\xf4\xf4\xe3\x08\x6a\x80\x6c\xfb\xad\x8a\x3a\xf7',
  >         ]}]
  >     fields eval:[b'linknode']
  >     haveparents eval:True
  >     pathfilter eval:{b'include': [b'path:dupe-file']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 1,
      b'totalpaths': 1
    },
    {
      b'path': b'dupe-file',
      b'totalitems': 1
    },
    {
      b'linknode': b'\xb1l\xce)g\xc1t\x9e\xf4\xf4\xe3\x08j\x80l\xfb\xad\x8a:\xf7',
      b'node': b'.\xd2\xa3\x91*\x0b$P C\xea\xe8N\xe4\xb2y\xc1\x8b\x90\xdd'
    }
  ]

Request for changeset where recorded linknode isn't in DAG ancestry will get
rewritten accordingly

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x47\xfc\x30\x58\x09\x11\x23\x2c\xb2\x64\x67\x5b\x40\x28\x19\xde\xdd\xf6\xc6\xf0',
  >         ]}]
  >     fields eval:[b'linknode']
  >     pathfilter eval:{b'include': [b'path:dupe-file']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 1,
      b'totalpaths': 1
    },
    {
      b'path': b'dupe-file',
      b'totalitems': 1
    },
    {
      b'linknode': b'G\xfc0X\t\x11#,\xb2dg[@(\x19\xde\xdd\xf6\xc6\xf0',
      b'node': b'.\xd2\xa3\x91*\x0b$P C\xea\xe8N\xe4\xb2y\xc1\x8b\x90\xdd'
    }
  ]

  $ sendhttpv2peer << EOF
  > command filesdata
  >     revisions eval:[{
  >         b'type': b'changesetexplicit',
  >         b'nodes': [
  >             b'\x47\xfc\x30\x58\x09\x11\x23\x2c\xb2\x64\x67\x5b\x40\x28\x19\xde\xdd\xf6\xc6\xf0',
  >         ]}]
  >     fields eval:[b'linknode']
  >     haveparents eval:True
  >     pathfilter eval:{b'include': [b'path:dupe-file']}
  > EOF
  creating http peer for wire protocol version 2
  sending filesdata command
  response: gen[
    {
      b'totalitems': 1,
      b'totalpaths': 1
    },
    {
      b'path': b'dupe-file',
      b'totalitems': 1
    },
    {
      b'linknode': b'G\xfc0X\t\x11#,\xb2dg[@(\x19\xde\xdd\xf6\xc6\xf0',
      b'node': b'.\xd2\xa3\x91*\x0b$P C\xea\xe8N\xe4\xb2y\xc1\x8b\x90\xdd'
    }
  ]

  $ cat error.log