comparison tests/test-revset.t @ 33377:5d63e5f40bea

revset: define successors revset

This revset returns all successors, including transit nodes and the source
nodes (to be consistent with existing revsets like "ancestors").

To filter out transit nodes, use `successors(X)-obsolete()`.
To filter out divergent case, use `successors(X)-divergent()-obsolete()`.

The revset could be useful to define rebase destination, like:
`max(successors(BASE)-divergent()-obsolete())`. The `max` is to deal with
splits.

There are other implementations where `successors` returns just one level of
successors, and `allsuccessors` returns everything. I think `successors`
returning all successors by default is more user friendly. We have seen
cases in production where people use 1-level `successors` while they really
want `allsuccessors`. So it seems better to just have one single revset
returning all successors by default to avoid user errors.

In the future we might want to add `depth` keyword argument to it and for
other revsets like `ancestors` etc. Or even build some flexible indexing
syntax [1] to satisfy people having the depth limit requirement.

[1]: https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-July/101140.html

33376:d5a38eae67e5

  > 
  > mercurial.revset.symbols['r3232'] = r3232
  > EOF
  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > testrevset=$TESTTMP/testrevset.py
  > EOF

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

  P=[1]
  $ P=3 hg --config revsetalias.P=2 log -r . -T '\n'
  P=[3]

  $ cd ..

33377:5d63e5f40bea

  > 
  > mercurial.revset.symbols['r3232'] = r3232
  > EOF
  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > drawdag=$TESTDIR/drawdag.py
  > testrevset=$TESTTMP/testrevset.py
  > EOF

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

  P=[1]
  $ P=3 hg --config revsetalias.P=2 log -r . -T '\n'
  P=[3]

  $ cd ..

Test obsstore related revsets

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

  $ 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)-divergent()' -T '{desc}\n'
  A
  Z
  B

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