tests/test-revset2.t
author Gregory Szorc <gregory.szorc@gmail.com>
Mon, 24 Sep 2018 09:41:42 -0700
changeset 39861 db5501d93bcf
parent 39707 5abc47d4ca6b
child 39912 7b35209ba1a7
permissions -rw-r--r--
changegroup: remove reordering control (BC) This logic - including the experimental bundle.reorder option - was originally added in a8e3931e3fb5 in 2011 and then later ported to changegroup.py. The intent of this option and associated logic is to control the ordering of revisions in deltagroups in changegroups. At the time it was implemented, only changegroup version 1 existed and generaldelta revlogs were just coming into the world. Changegroup version 1 requires that deltas be made against the last revision sent over the wire. Used with generaldelta, this created an impedance mismatch of sorts and resulted in changegroup producers spending a lot of time recomputing deltas. Revision reordering was introduced so outgoing revisions would be sent in "generaldelta order" and producers would be able to reuse internal deltas from storage. Later on, we introduced changegroup version 2. It supported denoting which revision a delta was against. So we no longer needed to sort outgoing revisions to ensure optimal delta generation from the producer. So, subsequent changegroup versions disabled reordering. We also later made the changelog not store deltas by default. And we also made the changelog send out deltas in storage order. Why we do this for changelog, I'm not sure. Maybe we want to preserve revision order across clones? It doesn't really matter for this commit. Fast forward to 2018. We want to abstract storage backends. And having changegroup code require knowledge about how deltas are stored internally interferes with that goal. This commit removes reordering control from changegroup generation. After this commit, the reordering behavior is: * The changelog is always sent out in storage order (no behavior change). * Non-changelog generaldelta revlogs are reordered to always be in DAG topological order (previously, generaldelta revlogs would be emitted in storage order for version 2 and 3 changegroups). * Non-changelog non-generaldelta revlogs are sent in storage order (no behavior change). * There exists no config option to override behavior. The big difference here is that generaldelta revlogs now *always* have their revisions sorted in DAG order before going out over the wire. This behavior was previously only done for changegroup version 1. Version 2 and version 3 changegroups disabled reordering because the interchange format supported encoding arbitrary delta parents, so reordering wasn't strictly necessary. I can think of a few significant implications for this change. Because changegroup receivers will now see non-changelog revisions in DAG order instead of storage order, the internal storage order of manifests and files may differ substantially between producer and consumer. I don't think this matters that much, since the storage order of manifests and files is largely hidden from users. Only the storage order of changelog matters (because `hg log` shows the changelog in storage order). I don't think there should be any controversy here. The reordering of revisions has implications for changegroup producers. Previously, generaldelta revlogs would be emitted in storage order. And in the common case, the internally-stored delta could effectively be copied from disk into the deltagroup delta. This meant that emitting delta groups for generaldelta revlogs would be mostly linear read I/O. This is desirable for performance. With us now reordering generaldelta revlog revisions in DAG order, the read operations may use more random I/O instead of sequential I/O. This could result in performance loss. But with the prevalence of SSDs and fast random I/O, I'm not too worried. (Note: the optimal emission order for revlogs is actually delta encoding order. But the changegroup code wasn't doing that before or after this change. We could potentially implement that in a later commit.) Changegroups in DAG order will have implications for receivers. Previously, receiving storage order might mean seeing a number of interleaved branches. This would mean long delta chains, sparse I/O, and possibly more fulltext revisions instead of deltas, blowing up storage storage. (This is the same set of problems that sparse revlogs aims to address.) With the producer now sending revisions in DAG order, the receiver also stores revisions in DAG order. That means revisions for the same DAG branch are all grouped together. And this should yield better storage outcomes. In other words, sending the reordered changegroup allows the receiver to have better storage order and for the producer to not propagate its (possibly sub-optimal) internal storage order. On the mozilla-unified repository, this change influences bundle generation: $ hg bundle -t none-v2 -a before: time: real 355.680 secs (user 256.790+0.000 sys 16.820+0.000) after: time: real 382.950 secs (user 281.700+0.000 sys 17.690+0.000) before: 7,150,228,967 bytes (uncompressed) after: 7,041,556,273 bytes (uncompressed) before: 1,669,063,234 bytes (zstd l=3) after: 1,628,598,830 bytes (zstd l=3) $ hg unbundle before: time: real 511.910 secs (user 466.750+0.000 sys 32.680+0.000) after: time: real 487.790 secs (user 443.940+0.000 sys 30.840+0.000) 00manifest.d size: source: 274,924,292 bytes before: 304,741,626 bytes after: 245,252,087 bytes .hg/store total file size: source: 2,649,133,490 before: 2,680,888,130 after: 2,627,875,673 We see the bundle size drop. That's probably because if a revlog internally isn't storing a delta, it will choose to delta against the last emitted revision. And on repos with interleaved branches (like mozilla-unified), the previous revision could be an unrelated branch and therefore be a large delta. But with this patch, the previous revision is likely p1 or p2 and a delta should be small. We also see the manifest size drop by ~50 MB. It's worth noting that the manifest actually *increased* in size by ~25 MB in the old strategy and decreased ~25 MB from its source in the new strategy. Again, my explanation for this is that the DAG ordering in the changegroup is resulting in better grouping of revisions in the receiver, which results in more compact delta chains and higher storage efficiency. Unbundle time also dropped. I suspect this is due to the revlog having to work less to compute deltas since the incoming deltas are more optimal. i.e. the receiver spends less time resolving fulltext revisions as incoming deltas bounce around between DAG branches and delta chains. We also see bundle generation time increase. This is not desirable. However, the regression is only significant on the original repository: if we generate a bundle from the repository created from the new, always reordered bundles, we're close to baseline (if not at it with expected noise): $ hg bundle -t none-v2 -a before (original): time: real 355.680 secs (user 256.790+0.000 sys 16.820+0.000) after (original): time: real 382.950 secs (user 281.700+0.000 sys 17.690+0.000) after (new repo): time: real 362.280 secs (user 260.300+0.000 sys 17.700+0.000) This regression is a bit worrying because it will impact serving canonical repositories (that don't have optimal internal storage unless they are reordered - possibly as part of running `hg debugupgraderepo`). However, this regression will only be noticed by very large changegroups. And I'm guessing/hoping that any repository that large is using clonebundles to mitigate server load. Again, sending DAG order isn't the optimal send order for servers: sending in storage-delta order is. But in order to enable storage-optimal send order, we'll need a storage API that handles sorting. Future commits will introduce such an API. Differential Revision: https://phab.mercurial-scm.org/D4721

  $ HGENCODING=utf-8
  $ export HGENCODING
  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > drawdag=$TESTDIR/drawdag.py
  > EOF

  $ try() {
  >   hg debugrevspec --debug "$@"
  > }

  $ log() {
  >   hg log --template '{rev}\n' -r "$1"
  > }

  $ hg init repo
  $ cd repo

  $ echo a > a
  $ hg branch a
  marked working directory as branch a
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -Aqm0

  $ echo b > b
  $ hg branch b
  marked working directory as branch b
  $ hg ci -Aqm1

  $ rm a
  $ hg branch a-b-c-
  marked working directory as branch a-b-c-
  $ hg ci -Aqm2 -u Bob

  $ hg log -r "extra('branch', 'a-b-c-')" --template '{rev}\n'
  2
  $ hg log -r "extra('branch')" --template '{rev}\n'
  0
  1
  2
  $ hg log -r "extra('branch', 're:a')" --template '{rev} {branch}\n'
  0 a
  2 a-b-c-

  $ hg co 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg branch +a+b+c+
  marked working directory as branch +a+b+c+
  $ hg ci -Aqm3

  $ hg co 2  # interleave
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo bb > b
  $ hg branch -- -a-b-c-
  marked working directory as branch -a-b-c-
  $ hg ci -Aqm4 -d "May 12 2005"

  $ hg co 3
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg branch !a/b/c/
  marked working directory as branch !a/b/c/
  $ hg ci -Aqm"5 bug"

  $ hg merge 4
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg branch _a_b_c_
  marked working directory as branch _a_b_c_
  $ hg ci -Aqm"6 issue619"

  $ hg branch .a.b.c.
  marked working directory as branch .a.b.c.
  $ hg ci -Aqm7

  $ hg branch all
  marked working directory as branch all

  $ hg co 4
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg branch é
  marked working directory as branch \xc3\xa9 (esc)
  $ hg ci -Aqm9

  $ hg tag -r6 1.0
  $ hg bookmark -r6 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

  $ hg clone --quiet -U -r 7 . ../remote1
  $ hg clone --quiet -U -r 8 . ../remote2
  $ echo "[paths]" >> .hg/hgrc
  $ echo "default = ../remote1" >> .hg/hgrc

test subtracting something from an addset

  $ log '(outgoing() or removes(a)) - removes(a)'
  8
  9

test intersecting something with an addset

  $ log 'parents(outgoing() or removes(a))'
  1
  4
  5
  8

test that `or` operation combines elements in the right order:

  $ log '3:4 or 2:5'
  3
  4
  2
  5
  $ log '3:4 or 5:2'
  3
  4
  5
  2
  $ log 'sort(3:4 or 2:5)'
  2
  3
  4
  5
  $ log 'sort(3:4 or 5:2)'
  2
  3
  4
  5

test that more than one `-r`s are combined in the right order and deduplicated:

  $ hg log -T '{rev}\n' -r 3 -r 3 -r 4 -r 5:2 -r 'ancestors(4)'
  3
  4
  5
  2
  0
  1

test that `or` operation skips duplicated revisions from right-hand side

  $ try 'reverse(1::5) or ancestors(4)'
  (or
    (list
      (func
        (symbol 'reverse')
        (dagrange
          (symbol '1')
          (symbol '5')))
      (func
        (symbol 'ancestors')
        (symbol '4'))))
  * set:
  <addset
    <baseset- [1, 3, 5]>,
    <generatorsetdesc+>>
  5
  3
  1
  0
  2
  4
  $ try 'sort(ancestors(4) or reverse(1::5))'
  (func
    (symbol 'sort')
    (or
      (list
        (func
          (symbol 'ancestors')
          (symbol '4'))
        (func
          (symbol 'reverse')
          (dagrange
            (symbol '1')
            (symbol '5'))))))
  * set:
  <addset+
    <generatorsetdesc+>,
    <baseset- [1, 3, 5]>>
  0
  1
  2
  3
  4
  5

test optimization of trivial `or` operation

  $ try --optimize '0|(1)|"2"|-2|tip|null'
  (or
    (list
      (symbol '0')
      (group
        (symbol '1'))
      (string '2')
      (negate
        (symbol '2'))
      (symbol 'tip')
      (symbol 'null')))
  * optimized:
  (func
    (symbol '_list')
    (string '0\x001\x002\x00-2\x00tip\x00null'))
  * set:
  <baseset [0, 1, 2, 8, 9, -1]>
  0
  1
  2
  8
  9
  -1

  $ try --optimize '0|1|2:3'
  (or
    (list
      (symbol '0')
      (symbol '1')
      (range
        (symbol '2')
        (symbol '3'))))
  * optimized:
  (or
    (list
      (func
        (symbol '_list')
        (string '0\x001'))
      (range
        (symbol '2')
        (symbol '3'))))
  * set:
  <addset
    <baseset [0, 1]>,
    <spanset+ 2:4>>
  0
  1
  2
  3

  $ try --optimize '0:1|2|3:4|5|6'
  (or
    (list
      (range
        (symbol '0')
        (symbol '1'))
      (symbol '2')
      (range
        (symbol '3')
        (symbol '4'))
      (symbol '5')
      (symbol '6')))
  * optimized:
  (or
    (list
      (range
        (symbol '0')
        (symbol '1'))
      (symbol '2')
      (range
        (symbol '3')
        (symbol '4'))
      (func
        (symbol '_list')
        (string '5\x006'))))
  * set:
  <addset
    <addset
      <spanset+ 0:2>,
      <baseset [2]>>,
    <addset
      <spanset+ 3:5>,
      <baseset [5, 6]>>>
  0
  1
  2
  3
  4
  5
  6

unoptimized `or` looks like this

  $ try --no-optimized -p analyzed '0|1|2|3|4'
  * analyzed:
  (or
    (list
      (symbol '0')
      (symbol '1')
      (symbol '2')
      (symbol '3')
      (symbol '4')))
  * set:
  <addset
    <addset
      <baseset [0]>,
      <baseset [1]>>,
    <addset
      <baseset [2]>,
      <addset
        <baseset [3]>,
        <baseset [4]>>>>
  0
  1
  2
  3
  4

test that `_list` should be narrowed by provided `subset`

  $ log '0:2 and (null|1|2|3)'
  1
  2

test that `_list` should remove duplicates

  $ log '0|1|2|1|2|-1|tip'
  0
  1
  2
  9

test unknown revision in `_list`

  $ log '0|unknown'
  abort: unknown revision 'unknown'!
  [255]

test integer range in `_list`

  $ log '-1|-10'
  9
  0

  $ log '-10|-11'
  abort: unknown revision '-11'!
  [255]

  $ log '9|10'
  abort: unknown revision '10'!
  [255]

test '0000' != '0' in `_list`

  $ log '0|0000'
  0
  -1

test ',' in `_list`
  $ log '0,1'
  hg: parse error: can't use a list in this context
  (see 'hg help "revsets.x or y"')
  [255]
  $ try '0,1,2'
  (list
    (symbol '0')
    (symbol '1')
    (symbol '2'))
  hg: parse error: can't use a list in this context
  (see 'hg help "revsets.x or y"')
  [255]

test that chained `or` operations make balanced addsets

  $ try '0:1|1:2|2:3|3:4|4:5'
  (or
    (list
      (range
        (symbol '0')
        (symbol '1'))
      (range
        (symbol '1')
        (symbol '2'))
      (range
        (symbol '2')
        (symbol '3'))
      (range
        (symbol '3')
        (symbol '4'))
      (range
        (symbol '4')
        (symbol '5'))))
  * set:
  <addset
    <addset
      <spanset+ 0:2>,
      <spanset+ 1:3>>,
    <addset
      <spanset+ 2:4>,
      <addset
        <spanset+ 3:5>,
        <spanset+ 4:6>>>>
  0
  1
  2
  3
  4
  5

no crash by empty group "()" while optimizing `or` operations

  $ try --optimize '0|()'
  (or
    (list
      (symbol '0')
      (group
        None)))
  * optimized:
  (or
    (list
      (symbol '0')
      None))
  hg: parse error: missing argument
  [255]

test that chained `or` operations never eat up stack (issue4624)
(uses `0:1` instead of `0` to avoid future optimization of trivial revisions)

  $ hg log -T '{rev}\n' -r `"$PYTHON" -c "print '+'.join(['0:1'] * 500)"`
  0
  1

test that repeated `-r` options never eat up stack (issue4565)
(uses `-r 0::1` to avoid possible optimization at old-style parser)

  $ hg log -T '{rev}\n' `"$PYTHON" -c "for i in range(500): print '-r 0::1 ',"`
  0
  1

check that conversion to only works
  $ try --optimize '::3 - ::1'
  (minus
    (dagrangepre
      (symbol '3'))
    (dagrangepre
      (symbol '1')))
  * optimized:
  (func
    (symbol 'only')
    (list
      (symbol '3')
      (symbol '1')))
  * set:
  <baseset+ [3]>
  3
  $ try --optimize 'ancestors(1) - ancestors(3)'
  (minus
    (func
      (symbol 'ancestors')
      (symbol '1'))
    (func
      (symbol 'ancestors')
      (symbol '3')))
  * optimized:
  (func
    (symbol 'only')
    (list
      (symbol '1')
      (symbol '3')))
  * set:
  <baseset+ []>
  $ try --optimize 'not ::2 and ::6'
  (and
    (not
      (dagrangepre
        (symbol '2')))
    (dagrangepre
      (symbol '6')))
  * optimized:
  (func
    (symbol 'only')
    (list
      (symbol '6')
      (symbol '2')))
  * set:
  <baseset+ [3, 4, 5, 6]>
  3
  4
  5
  6
  $ try --optimize 'ancestors(6) and not ancestors(4)'
  (and
    (func
      (symbol 'ancestors')
      (symbol '6'))
    (not
      (func
        (symbol 'ancestors')
        (symbol '4'))))
  * optimized:
  (func
    (symbol 'only')
    (list
      (symbol '6')
      (symbol '4')))
  * set:
  <baseset+ [3, 5, 6]>
  3
  5
  6

no crash by empty group "()" while optimizing to "only()"

  $ try --optimize '::1 and ()'
  (and
    (dagrangepre
      (symbol '1'))
    (group
      None))
  * optimized:
  (andsmally
    (func
      (symbol 'ancestors')
      (symbol '1'))
    None)
  hg: parse error: missing argument
  [255]

optimization to only() works only if ancestors() takes only one argument

  $ hg debugrevspec -p optimized 'ancestors(6) - ancestors(4, 1)'
  * optimized:
  (difference
    (func
      (symbol 'ancestors')
      (symbol '6'))
    (func
      (symbol 'ancestors')
      (list
        (symbol '4')
        (symbol '1'))))
  0
  1
  3
  5
  6
  $ hg debugrevspec -p optimized 'ancestors(6, 1) - ancestors(4)'
  * optimized:
  (difference
    (func
      (symbol 'ancestors')
      (list
        (symbol '6')
        (symbol '1')))
    (func
      (symbol 'ancestors')
      (symbol '4')))
  5
  6

optimization disabled if keyword arguments passed (because we're too lazy
to support it)

  $ hg debugrevspec -p optimized 'ancestors(set=6) - ancestors(set=4)'
  * optimized:
  (difference
    (func
      (symbol 'ancestors')
      (keyvalue
        (symbol 'set')
        (symbol '6')))
    (func
      (symbol 'ancestors')
      (keyvalue
        (symbol 'set')
        (symbol '4'))))
  3
  5
  6

invalid function call should not be optimized to only()

  $ log '"ancestors"(6) and not ancestors(4)'
  hg: parse error: not a symbol
  [255]

  $ log 'ancestors(6) and not "ancestors"(4)'
  hg: parse error: not a symbol
  [255]

test empty string

  $ log ''
  hg: parse error: empty query
  [255]
  $ log 'parents("")'
  hg: parse error: empty string is not a valid revision
  [255]

test empty revset
  $ hg log 'none()'

we can use patterns when searching for tags

  $ log 'tag("1..*")'
  abort: tag '1..*' does not exist!
  [255]
  $ log 'tag("re:1..*")'
  6
  $ log 'tag("re:[0-9].[0-9]")'
  6
  $ log 'tag("literal:1.0")'
  6
  $ log 'tag("re:0..*")'

  $ log 'tag(unknown)'
  abort: tag 'unknown' does not exist!
  [255]
  $ log 'tag("re:unknown")'
  $ log 'present(tag("unknown"))'
  $ log 'present(tag("re:unknown"))'
  $ log 'branch(unknown)'
  abort: unknown revision 'unknown'!
  [255]
  $ log 'branch("literal:unknown")'
  abort: branch 'unknown' does not exist!
  [255]
  $ log 'branch("re:unknown")'
  $ log 'present(branch("unknown"))'
  $ log 'present(branch("re:unknown"))'
  $ log 'user(bob)'
  2

  $ log '4::8'
  4
  8
  $ log '4:8'
  4
  5
  6
  7
  8

  $ log 'sort(!merge() & (modifies(b) | user(bob) | keyword(bug) | keyword(issue) & 1::9), "-date")'
  4
  2
  5

  $ log 'not 0 and 0:2'
  1
  2
  $ log 'not 1 and 0:2'
  0
  2
  $ log 'not 2 and 0:2'
  0
  1
  $ log '(1 and 2)::'
  $ log '(1 and 2):'
  $ log '(1 and 2):3'
  $ log 'sort(head(), -rev)'
  9
  7
  6
  5
  4
  3
  2
  1
  0
  $ log '4::8 - 8'
  4

matching() should preserve the order of the input set:

  $ log '(2 or 3 or 1) and matching(1 or 2 or 3)'
  2
  3
  1

  $ log 'named("unknown")'
  abort: namespace 'unknown' does not exist!
  [255]
  $ log 'named("re:unknown")'
  abort: no namespace exists that match 'unknown'!
  [255]
  $ log 'present(named("unknown"))'
  $ log 'present(named("re:unknown"))'

  $ log 'tag()'
  6
  $ log 'named("tags")'
  6

issue2437

  $ log '3 and p1(5)'
  3
  $ log '4 and p2(6)'
  4
  $ log '1 and parents(:2)'
  1
  $ log '2 and children(1:)'
  2
  $ log 'roots(all()) or roots(all())'
  0
  $ hg debugrevspec 'roots(all()) or roots(all())'
  0
  $ log 'heads(branch(é)) or heads(branch(é))'
  9
  $ log 'ancestors(8) and (heads(branch("-a-b-c-")) or heads(branch(é)))'
  4

issue2654: report a parse error if the revset was not completely parsed

  $ log '1 OR 2'
  hg: parse error at 2: invalid token
  (1 OR 2
     ^ here)
  [255]

or operator should preserve ordering:
  $ log 'reverse(2::4) or tip'
  4
  2
  9

parentrevspec

  $ log 'merge()^0'
  6
  $ log 'merge()^'
  5
  $ log 'merge()^1'
  5
  $ log 'merge()^2'
  4
  $ log '(not merge())^2'
  $ log 'merge()^^'
  3
  $ log 'merge()^1^'
  3
  $ log 'merge()^^^'
  1

  $ hg debugrevspec -s '(merge() | 0)~-1'
  * set:
  <baseset+ [1, 7]>
  1
  7
  $ log 'merge()~-1'
  7
  $ log 'tip~-1'
  $ log '(tip | merge())~-1'
  7
  $ log 'merge()~0'
  6
  $ log 'merge()~1'
  5
  $ log 'merge()~2'
  3
  $ log 'merge()~2^1'
  1
  $ log 'merge()~3'
  1

  $ log '(-3:tip)^'
  4
  6
  8

  $ log 'tip^foo'
  hg: parse error: ^ expects a number 0, 1, or 2
  [255]

  $ log 'branchpoint()~-1'
  abort: revision in set has more than one child!
  [255]

Bogus function gets suggestions
  $ log 'add()'
  hg: parse error: unknown identifier: add
  (did you mean adds?)
  [255]
  $ log 'added()'
  hg: parse error: unknown identifier: added
  (did you mean adds?)
  [255]
  $ log 'remo()'
  hg: parse error: unknown identifier: remo
  (did you mean one of remote, removes?)
  [255]
  $ log 'babar()'
  hg: parse error: unknown identifier: babar
  [255]

Bogus function with a similar internal name doesn't suggest the internal name
  $ log 'matches()'
  hg: parse error: unknown identifier: matches
  (did you mean matching?)
  [255]

Undocumented functions aren't suggested as similar either
  $ log 'tagged2()'
  hg: parse error: unknown identifier: tagged2
  [255]

multiple revspecs

  $ hg log -r 'tip~1:tip' -r 'tip~2:tip~1' --template '{rev}\n'
  8
  9
  4
  5
  6
  7

test usage in revpair (with "+")

(real pair)

  $ hg diff -r 'tip^^' -r 'tip'
  diff -r 2326846efdab -r 24286f4ae135 .hgtags
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/.hgtags	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +e0cc66ef77e8b6f711815af4e001a6594fde3ba5 1.0
  $ hg diff -r 'tip^^::tip'
  diff -r 2326846efdab -r 24286f4ae135 .hgtags
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/.hgtags	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +e0cc66ef77e8b6f711815af4e001a6594fde3ba5 1.0

(single rev)

  $ hg diff -r 'tip^' -r 'tip^'
  $ hg diff -r 'tip^:tip^'

(single rev that does not looks like a range)

  $ hg diff -r 'tip^::tip^ or tip^'
  diff -r d5d0dcbdc4d9 .hgtags
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/.hgtags	* (glob)
  @@ -0,0 +1,1 @@
  +e0cc66ef77e8b6f711815af4e001a6594fde3ba5 1.0
  $ hg diff -r 'tip^ or tip^'
  diff -r d5d0dcbdc4d9 .hgtags
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/.hgtags	* (glob)
  @@ -0,0 +1,1 @@
  +e0cc66ef77e8b6f711815af4e001a6594fde3ba5 1.0

(no rev)

  $ hg diff -r 'author("babar") or author("celeste")'
  abort: empty revision range
  [255]

aliases:

  $ echo '[revsetalias]' >> .hg/hgrc
  $ echo 'm = merge()' >> .hg/hgrc
(revset aliases can override builtin revsets)
  $ echo 'p2($1) = p1($1)' >> .hg/hgrc
  $ echo 'sincem = descendants(m)' >> .hg/hgrc
  $ echo 'd($1) = reverse(sort($1, date))' >> .hg/hgrc
  $ echo 'rs(ARG1, ARG2) = reverse(sort(ARG1, ARG2))' >> .hg/hgrc
  $ echo 'rs4(ARG1, ARGA, ARGB, ARG2) = reverse(sort(ARG1, ARG2))' >> .hg/hgrc

  $ try m
  (symbol 'm')
  * expanded:
  (func
    (symbol 'merge')
    None)
  * set:
  <filteredset
    <fullreposet+ 0:10>,
    <merge>>
  6

  $ HGPLAIN=1
  $ export HGPLAIN
  $ try m
  (symbol 'm')
  abort: unknown revision 'm'!
  [255]

  $ HGPLAINEXCEPT=revsetalias
  $ export HGPLAINEXCEPT
  $ try m
  (symbol 'm')
  * expanded:
  (func
    (symbol 'merge')
    None)
  * set:
  <filteredset
    <fullreposet+ 0:10>,
    <merge>>
  6

  $ unset HGPLAIN
  $ unset HGPLAINEXCEPT

  $ try 'p2(.)'
  (func
    (symbol 'p2')
    (symbol '.'))
  * expanded:
  (func
    (symbol 'p1')
    (symbol '.'))
  * set:
  <baseset+ [8]>
  8

  $ HGPLAIN=1
  $ export HGPLAIN
  $ try 'p2(.)'
  (func
    (symbol 'p2')
    (symbol '.'))
  * set:
  <baseset+ []>

  $ HGPLAINEXCEPT=revsetalias
  $ export HGPLAINEXCEPT
  $ try 'p2(.)'
  (func
    (symbol 'p2')
    (symbol '.'))
  * expanded:
  (func
    (symbol 'p1')
    (symbol '.'))
  * set:
  <baseset+ [8]>
  8

  $ unset HGPLAIN
  $ unset HGPLAINEXCEPT

test alias recursion

  $ try sincem
  (symbol 'sincem')
  * expanded:
  (func
    (symbol 'descendants')
    (func
      (symbol 'merge')
      None))
  * set:
  <generatorsetasc+>
  6
  7

test infinite recursion

  $ echo 'recurse1 = recurse2' >> .hg/hgrc
  $ echo 'recurse2 = recurse1' >> .hg/hgrc
  $ try recurse1
  (symbol 'recurse1')
  hg: parse error: infinite expansion of revset alias "recurse1" detected
  [255]

  $ echo 'level1($1, $2) = $1 or $2' >> .hg/hgrc
  $ echo 'level2($1, $2) = level1($2, $1)' >> .hg/hgrc
  $ try "level2(level1(1, 2), 3)"
  (func
    (symbol 'level2')
    (list
      (func
        (symbol 'level1')
        (list
          (symbol '1')
          (symbol '2')))
      (symbol '3')))
  * expanded:
  (or
    (list
      (symbol '3')
      (or
        (list
          (symbol '1')
          (symbol '2')))))
  * set:
  <addset
    <baseset [3]>,
    <baseset [1, 2]>>
  3
  1
  2

test nesting and variable passing

  $ echo 'nested($1) = nested2($1)' >> .hg/hgrc
  $ echo 'nested2($1) = nested3($1)' >> .hg/hgrc
  $ echo 'nested3($1) = max($1)' >> .hg/hgrc
  $ try 'nested(2:5)'
  (func
    (symbol 'nested')
    (range
      (symbol '2')
      (symbol '5')))
  * expanded:
  (func
    (symbol 'max')
    (range
      (symbol '2')
      (symbol '5')))
  * set:
  <baseset
    <max
      <fullreposet+ 0:10>,
      <spanset+ 2:6>>>
  5

test chained `or` operations are flattened at parsing phase

  $ echo 'chainedorops($1, $2, $3) = $1|$2|$3' >> .hg/hgrc
  $ try 'chainedorops(0:1, 1:2, 2:3)'
  (func
    (symbol 'chainedorops')
    (list
      (range
        (symbol '0')
        (symbol '1'))
      (range
        (symbol '1')
        (symbol '2'))
      (range
        (symbol '2')
        (symbol '3'))))
  * expanded:
  (or
    (list
      (range
        (symbol '0')
        (symbol '1'))
      (range
        (symbol '1')
        (symbol '2'))
      (range
        (symbol '2')
        (symbol '3'))))
  * set:
  <addset
    <spanset+ 0:2>,
    <addset
      <spanset+ 1:3>,
      <spanset+ 2:4>>>
  0
  1
  2
  3

test variable isolation, variable placeholders are rewritten as string
then parsed and matched again as string. Check they do not leak too
far away.

  $ echo 'injectparamasstring = max("$1")' >> .hg/hgrc
  $ echo 'callinjection($1) = descendants(injectparamasstring)' >> .hg/hgrc
  $ try 'callinjection(2:5)'
  (func
    (symbol 'callinjection')
    (range
      (symbol '2')
      (symbol '5')))
  * expanded:
  (func
    (symbol 'descendants')
    (func
      (symbol 'max')
      (string '$1')))
  abort: unknown revision '$1'!
  [255]

test scope of alias expansion: 'universe' is expanded prior to 'shadowall(0)',
but 'all()' should never be substituted to '0()'.

  $ echo 'universe = all()' >> .hg/hgrc
  $ echo 'shadowall(all) = all and universe' >> .hg/hgrc
  $ try 'shadowall(0)'
  (func
    (symbol 'shadowall')
    (symbol '0'))
  * expanded:
  (and
    (symbol '0')
    (func
      (symbol 'all')
      None))
  * set:
  <filteredset
    <baseset [0]>,
    <spanset+ 0:10>>
  0

test unknown reference:

  $ try "unknownref(0)" --config 'revsetalias.unknownref($1)=$1:$2'
  (func
    (symbol 'unknownref')
    (symbol '0'))
  abort: bad definition of revset alias "unknownref": invalid symbol '$2'
  [255]

  $ hg debugrevspec --debug --config revsetalias.anotherbadone='branch(' "tip"
  (symbol 'tip')
  warning: bad definition of revset alias "anotherbadone": at 7: not a prefix: end
  * set:
  <baseset [9]>
  9

  $ try 'tip'
  (symbol 'tip')
  * set:
  <baseset [9]>
  9

  $ hg debugrevspec --debug --config revsetalias.'bad name'='tip' "tip"
  (symbol 'tip')
  warning: bad declaration of revset alias "bad name": at 4: invalid token
  * set:
  <baseset [9]>
  9
  $ echo 'strictreplacing($1, $10) = $10 or desc("$1")' >> .hg/hgrc
  $ try 'strictreplacing("foo", tip)'
  (func
    (symbol 'strictreplacing')
    (list
      (string 'foo')
      (symbol 'tip')))
  * expanded:
  (or
    (list
      (symbol 'tip')
      (func
        (symbol 'desc')
        (string '$1'))))
  * set:
  <addset
    <baseset [9]>,
    <filteredset
      <fullreposet+ 0:10>,
      <desc '$1'>>>
  9

  $ try 'd(2:5)'
  (func
    (symbol 'd')
    (range
      (symbol '2')
      (symbol '5')))
  * expanded:
  (func
    (symbol 'reverse')
    (func
      (symbol 'sort')
      (list
        (range
          (symbol '2')
          (symbol '5'))
        (symbol 'date'))))
  * set:
  <baseset [4, 5, 3, 2]>
  4
  5
  3
  2
  $ try 'rs(2 or 3, date)'
  (func
    (symbol 'rs')
    (list
      (or
        (list
          (symbol '2')
          (symbol '3')))
      (symbol 'date')))
  * expanded:
  (func
    (symbol 'reverse')
    (func
      (symbol 'sort')
      (list
        (or
          (list
            (symbol '2')
            (symbol '3')))
        (symbol 'date'))))
  * set:
  <baseset [3, 2]>
  3
  2
  $ try 'rs()'
  (func
    (symbol 'rs')
    None)
  hg: parse error: invalid number of arguments: 0
  [255]
  $ try 'rs(2)'
  (func
    (symbol 'rs')
    (symbol '2'))
  hg: parse error: invalid number of arguments: 1
  [255]
  $ try 'rs(2, data, 7)'
  (func
    (symbol 'rs')
    (list
      (symbol '2')
      (symbol 'data')
      (symbol '7')))
  hg: parse error: invalid number of arguments: 3
  [255]
  $ try 'rs4(2 or 3, x, x, date)'
  (func
    (symbol 'rs4')
    (list
      (or
        (list
          (symbol '2')
          (symbol '3')))
      (symbol 'x')
      (symbol 'x')
      (symbol 'date')))
  * expanded:
  (func
    (symbol 'reverse')
    (func
      (symbol 'sort')
      (list
        (or
          (list
            (symbol '2')
            (symbol '3')))
        (symbol 'date'))))
  * set:
  <baseset [3, 2]>
  3
  2

issue4553: check that revset aliases override existing hash prefix

  $ hg log -qr e
  6:e0cc66ef77e8

  $ hg log -qr e --config revsetalias.e="all()"
  0:2785f51eece5
  1:d75937da8da0
  2:5ed5505e9f1c
  3:8528aa5637f2
  4:2326846efdab
  5:904fa392b941
  6:e0cc66ef77e8
  7:013af1973af4
  8:d5d0dcbdc4d9
  9:24286f4ae135

  $ hg log -qr e: --config revsetalias.e="0"
  0:2785f51eece5
  1:d75937da8da0
  2:5ed5505e9f1c
  3:8528aa5637f2
  4:2326846efdab
  5:904fa392b941
  6:e0cc66ef77e8
  7:013af1973af4
  8:d5d0dcbdc4d9
  9:24286f4ae135

  $ hg log -qr :e --config revsetalias.e="9"
  0:2785f51eece5
  1:d75937da8da0
  2:5ed5505e9f1c
  3:8528aa5637f2
  4:2326846efdab
  5:904fa392b941
  6:e0cc66ef77e8
  7:013af1973af4
  8:d5d0dcbdc4d9
  9:24286f4ae135

  $ hg log -qr e:
  6:e0cc66ef77e8
  7:013af1973af4
  8:d5d0dcbdc4d9
  9:24286f4ae135

  $ hg log -qr :e
  0:2785f51eece5
  1:d75937da8da0
  2:5ed5505e9f1c
  3:8528aa5637f2
  4:2326846efdab
  5:904fa392b941
  6:e0cc66ef77e8

issue2549 - correct optimizations

  $ try 'limit(1 or 2 or 3, 2) and not 2'
  (and
    (func
      (symbol 'limit')
      (list
        (or
          (list
            (symbol '1')
            (symbol '2')
            (symbol '3')))
        (symbol '2')))
    (not
      (symbol '2')))
  * set:
  <filteredset
    <baseset [1, 2]>,
    <not
      <baseset [2]>>>
  1
  $ try 'max(1 or 2) and not 2'
  (and
    (func
      (symbol 'max')
      (or
        (list
          (symbol '1')
          (symbol '2'))))
    (not
      (symbol '2')))
  * set:
  <filteredset
    <baseset
      <max
        <fullreposet+ 0:10>,
        <baseset [1, 2]>>>,
    <not
      <baseset [2]>>>
  $ try 'min(1 or 2) and not 1'
  (and
    (func
      (symbol 'min')
      (or
        (list
          (symbol '1')
          (symbol '2'))))
    (not
      (symbol '1')))
  * set:
  <filteredset
    <baseset
      <min
        <fullreposet+ 0:10>,
        <baseset [1, 2]>>>,
    <not
      <baseset [1]>>>
  $ try 'last(1 or 2, 1) and not 2'
  (and
    (func
      (symbol 'last')
      (list
        (or
          (list
            (symbol '1')
            (symbol '2')))
        (symbol '1')))
    (not
      (symbol '2')))
  * set:
  <filteredset
    <baseset [2]>,
    <not
      <baseset [2]>>>

issue4289 - ordering of built-ins
  $ hg log -M -q -r 3:2
  3:8528aa5637f2
  2:5ed5505e9f1c

test revsets started with 40-chars hash (issue3669)

  $ ISSUE3669_TIP=`hg tip --template '{node}'`
  $ hg log -r "${ISSUE3669_TIP}" --template '{rev}\n'
  9
  $ hg log -r "${ISSUE3669_TIP}^" --template '{rev}\n'
  8

test or-ed indirect predicates (issue3775)

  $ log '6 or 6^1' | sort
  5
  6
  $ log '6^1 or 6' | sort
  5
  6
  $ log '4 or 4~1' | sort
  2
  4
  $ log '4~1 or 4' | sort
  2
  4
  $ log '(0 or 2):(4 or 6) or 0 or 6' | sort
  0
  1
  2
  3
  4
  5
  6
  $ log '0 or 6 or (0 or 2):(4 or 6)' | sort
  0
  1
  2
  3
  4
  5
  6

tests for 'remote()' predicate:
#.  (csets in remote) (id)            (remote)
1.  less than local   current branch  "default"
2.  same with local   specified       "default"
3.  more than local   specified       specified

  $ hg clone --quiet -U . ../remote3
  $ cd ../remote3
  $ hg update -q 7
  $ echo r > r
  $ hg ci -Aqm 10
  $ log 'remote()'
  7
  $ log 'remote("a-b-c-")'
  2
  $ cd ../repo
  $ log 'remote(".a.b.c.", "../remote3")'

tests for concatenation of strings/symbols by "##"

  $ try "278 ## '5f5' ## 1ee ## 'ce5'"
  (_concat
    (_concat
      (_concat
        (symbol '278')
        (string '5f5'))
      (symbol '1ee'))
    (string 'ce5'))
  * concatenated:
  (string '2785f51eece5')
  * set:
  <baseset [0]>
  0

  $ echo 'cat4($1, $2, $3, $4) = $1 ## $2 ## $3 ## $4' >> .hg/hgrc
  $ try "cat4(278, '5f5', 1ee, 'ce5')"
  (func
    (symbol 'cat4')
    (list
      (symbol '278')
      (string '5f5')
      (symbol '1ee')
      (string 'ce5')))
  * expanded:
  (_concat
    (_concat
      (_concat
        (symbol '278')
        (string '5f5'))
      (symbol '1ee'))
    (string 'ce5'))
  * concatenated:
  (string '2785f51eece5')
  * set:
  <baseset [0]>
  0

(check concatenation in alias nesting)

  $ echo 'cat2($1, $2) = $1 ## $2' >> .hg/hgrc
  $ echo 'cat2x2($1, $2, $3, $4) = cat2($1 ## $2, $3 ## $4)' >> .hg/hgrc
  $ log "cat2x2(278, '5f5', 1ee, 'ce5')"
  0

(check operator priority)

  $ echo 'cat2n2($1, $2, $3, $4) = $1 ## $2 or $3 ## $4~2' >> .hg/hgrc
  $ log "cat2n2(2785f5, 1eece5, 24286f, 4ae135)"
  0
  4

  $ cd ..

prepare repository that has "default" branches of multiple roots

  $ hg init namedbranch
  $ cd namedbranch

  $ echo default0 >> a
  $ hg ci -Aqm0
  $ echo default1 >> a
  $ hg ci -m1

  $ hg branch -q stable
  $ echo stable2 >> a
  $ hg ci -m2
  $ echo stable3 >> a
  $ hg ci -m3

  $ hg update -q null
  $ echo default4 >> a
  $ hg ci -Aqm4
  $ echo default5 >> a
  $ hg ci -m5

"null" revision belongs to "default" branch (issue4683)

  $ log 'branch(null)'
  0
  1
  4
  5

"null" revision belongs to "default" branch, but it shouldn't appear in set
unless explicitly specified (issue4682)

  $ log 'children(branch(default))'
  1
  2
  5

  $ cd ..

test author/desc/keyword in problematic encoding
# unicode: cp932:
# u30A2    0x83 0x41(= 'A')
# u30C2    0x83 0x61(= 'a')

  $ hg init problematicencoding
  $ cd problematicencoding

  $ "$PYTHON" > setup.sh <<EOF
  > print u'''
  > echo a > text
  > hg add text
  > hg --encoding utf-8 commit -u '\u30A2' -m none
  > echo b > text
  > hg --encoding utf-8 commit -u '\u30C2' -m none
  > echo c > text
  > hg --encoding utf-8 commit -u none -m '\u30A2'
  > echo d > text
  > hg --encoding utf-8 commit -u none -m '\u30C2'
  > '''.encode('utf-8')
  > EOF
  $ sh < setup.sh

test in problematic encoding
  $ "$PYTHON" > test.sh <<EOF
  > print u'''
  > hg --encoding cp932 log --template '{rev}\\n' -r 'author(\u30A2)'
  > echo ====
  > hg --encoding cp932 log --template '{rev}\\n' -r 'author(\u30C2)'
  > echo ====
  > hg --encoding cp932 log --template '{rev}\\n' -r 'desc(\u30A2)'
  > echo ====
  > hg --encoding cp932 log --template '{rev}\\n' -r 'desc(\u30C2)'
  > echo ====
  > hg --encoding cp932 log --template '{rev}\\n' -r 'keyword(\u30A2)'
  > echo ====
  > hg --encoding cp932 log --template '{rev}\\n' -r 'keyword(\u30C2)'
  > '''.encode('cp932')
  > EOF
  $ sh < test.sh
  0
  ====
  1
  ====
  2
  ====
  3
  ====
  0
  2
  ====
  1
  3

test error message of bad revset
  $ hg log -r 'foo\\'
  hg: parse error at 3: syntax error in revset 'foo\\'
  (foo\\
      ^ here)
  [255]

  $ cd ..

Test that revset predicate of extension isn't loaded at failure of
loading it

  $ cd repo

  $ cat <<EOF > $TESTTMP/custompredicate.py
  > from mercurial import error, registrar, revset
  > 
  > revsetpredicate = registrar.revsetpredicate()
  > 
  > @revsetpredicate(b'custom1()')
  > def custom1(repo, subset, x):
  >     return revset.baseset([1])
  > 
  > raise error.Abort(b'intentional failure of loading extension')
  > EOF
  $ cat <<EOF > .hg/hgrc
  > [extensions]
  > custompredicate = $TESTTMP/custompredicate.py
  > EOF

  $ hg debugrevspec "custom1()"
  *** failed to import extension custompredicate from $TESTTMP/custompredicate.py: intentional failure of loading extension
  hg: parse error: unknown identifier: custom1
  [255]

Test repo.anyrevs with customized revset overrides

  $ cat > $TESTTMP/printprevset.py <<EOF
  > from mercurial import encoding, registrar
  > cmdtable = {}
  > command = registrar.command(cmdtable)
  > @command(b'printprevset')
  > def printprevset(ui, repo):
  >     alias = {}
  >     p = encoding.environ.get(b'P')
  >     if p:
  >         alias[b'P'] = p
  >     revs = repo.anyrevs([b'P'], user=True, localalias=alias)
  >     ui.write(b'P=%r\n' % list(revs))
  > EOF

  $ cat >> .hg/hgrc <<EOF
  > custompredicate = !
  > printprevset = $TESTTMP/printprevset.py
  > EOF

  $ hg --config revsetalias.P=1 printprevset
  P=[1]
  $ P=3 hg --config revsetalias.P=2 printprevset
  P=[3]

  $ cd ..

Test obsstore related revsets

  $ hg init repo1
  $ cd repo1
  $ cat <<EOF >> .hg/hgrc
  > [experimental]
  > evolution.createmarkers=True
  > EOF

  $ hg debugdrawdag <<'EOS'
  >        F G
  >        |/    # split: B -> E, F
  > B C D  E     # amend: B -> C -> D
  >  \|/   |     # amend: F -> G
  >   A    A  Z  # amend: A -> Z
  > EOS
  3 new orphan changesets
  3 new content-divergent changesets

  $ hg log -r 'successors(Z)' -T '{desc}\n'
  Z

  $ hg log -r 'successors(F)' -T '{desc}\n'
  F
  G

  $ hg tag --remove --local C D E F G

  $ hg log -r 'successors(B)' -T '{desc}\n'
  B
  D
  E
  G

  $ hg log -r 'successors(B)' -T '{desc}\n' --hidden
  B
  C
  D
  E
  F
  G

  $ hg log -r 'successors(B)-obsolete()' -T '{desc}\n' --hidden
  D
  E
  G

  $ hg log -r 'successors(B+A)-contentdivergent()' -T '{desc}\n'
  A
  Z
  B

  $ hg log -r 'successors(B+A)-contentdivergent()-obsolete()' -T '{desc}\n'
  Z

Test `draft() & ::x` optimization

  $ hg init $TESTTMP/repo2
  $ cd $TESTTMP/repo2
  $ hg debugdrawdag <<'EOS'
  >   P5 S1
  >    |  |
  > S2 | D3
  >   \|/
  >   P4
  >    |
  >   P3 D2
  >    |  |
  >   P2 D1
  >    |/
  >   P1
  >    |
  >   P0
  > EOS
  $ hg phase --public -r P5
  $ hg phase --force --secret -r S1+S2
  $ hg log -G -T '{rev} {desc} {phase}' -r 'sort(all(), topo, topo.firstbranch=P5)'
  o  8 P5 public
  |
  | o  10 S1 secret
  | |
  | o  7 D3 draft
  |/
  | o  9 S2 secret
  |/
  o  6 P4 public
  |
  o  5 P3 public
  |
  o  3 P2 public
  |
  | o  4 D2 draft
  | |
  | o  2 D1 draft
  |/
  o  1 P1 public
  |
  o  0 P0 public
  
  $ hg debugrevspec --verify -p analyzed -p optimized 'draft() & ::(((S1+D1+P5)-D3)+S2)'
  * analyzed:
  (and
    (func
      (symbol 'draft')
      None)
    (func
      (symbol 'ancestors')
      (or
        (list
          (and
            (or
              (list
                (symbol 'S1')
                (symbol 'D1')
                (symbol 'P5')))
            (not
              (symbol 'D3')))
          (symbol 'S2')))))
  * optimized:
  (func
    (symbol '_phaseandancestors')
    (list
      (symbol 'draft')
      (or
        (list
          (difference
            (func
              (symbol '_list')
              (string 'S1\x00D1\x00P5'))
            (symbol 'D3'))
          (symbol 'S2')))))
  $ hg debugrevspec --verify -p analyzed -p optimized 'secret() & ::9'
  * analyzed:
  (and
    (func
      (symbol 'secret')
      None)
    (func
      (symbol 'ancestors')
      (symbol '9')))
  * optimized:
  (func
    (symbol '_phaseandancestors')
    (list
      (symbol 'secret')
      (symbol '9')))
  $ hg debugrevspec --verify -p analyzed -p optimized '7 & ( (not public()) & ::(tag()) )'
  * analyzed:
  (and
    (symbol '7')
    (and
      (not
        (func
          (symbol 'public')
          None))
      (func
        (symbol 'ancestors')
        (func
          (symbol 'tag')
          None))))
  * optimized:
  (and
    (symbol '7')
    (func
      (symbol '_phaseandancestors')
      (list
        (symbol '_notpublic')
        (func
          (symbol 'tag')
          None))))
  $ hg debugrevspec --verify -p optimized '(not public()) & ancestors(S1+D2+P5, 1)'
  * optimized:
  (and
    (func
      (symbol '_notpublic')
      None)
    (func
      (symbol 'ancestors')
      (list
        (func
          (symbol '_list')
          (string 'S1\x00D2\x00P5'))
        (symbol '1'))))
  $ hg debugrevspec --verify -p optimized '(not public()) & ancestors(S1+D2+P5, depth=1)'
  * optimized:
  (and
    (func
      (symbol '_notpublic')
      None)
    (func
      (symbol 'ancestors')
      (list
        (func
          (symbol '_list')
          (string 'S1\x00D2\x00P5'))
        (keyvalue
          (symbol 'depth')
          (symbol '1')))))

test commonancestors and its optimization

  $ hg debugrevspec --verify -p analyzed -p optimized 'heads(commonancestors(head()))'
  * analyzed:
  (func
    (symbol 'heads')
    (func
      (symbol 'commonancestors')
      (func
        (symbol 'head')
        None)))
  * optimized:
  (func
    (symbol '_commonancestorheads')
    (func
      (symbol 'head')
      None))