view tests/test-show-stack.t @ 41247:a89b20a49c13

rust-cpython: using MissingAncestors from Python code

As precedently done with LazyAncestors on cpython.rs, we test for the
presence of the 'rustext' module.

incrementalmissingrevs() has two callers within the Mercurial core:
`setdiscovery.partialdiscovery` and the `only()` revset.

This move shows a significant discovery performance improvement
in cases where the baseline is slow: using perfdiscovery on the PyPy
repos, prepared with `contrib/discovery-helper <repo> 50 100`, we
get averaged medians of 403ms with the Rust version vs 742ms without
(about 45% better).

But there are still indications that performance can be worse in cases
the baseline is fast, possibly due to the conversion from Python to
Rust and back becoming the bottleneck. We could measure this on
mozilla-central in cases were the delta is just a few changesets.
This requires confirmation, but if that's the reason, then an
upcoming `partialdiscovery` fully in Rust should solve the problem.

Differential Revision: https://phab.mercurial-scm.org/D5551

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > show =
  > EOF

  $ hg init repo0
  $ cd repo0

Empty repo / no checkout results in error

  $ hg show stack
  abort: stack view only available when there is a working directory
  [255]

Stack displays single draft changeset as root revision

  $ echo 0 > foo
  $ hg -q commit -A -m 'commit 0'
  $ hg show stack
    @  9f17 commit 0

Stack displays multiple draft changesets

  $ echo 1 > foo
  $ hg commit -m 'commit 1'
  $ echo 2 > foo
  $ hg commit -m 'commit 2'
  $ echo 3 > foo
  $ hg commit -m 'commit 3'
  $ echo 4 > foo
  $ hg commit -m 'commit 4'
  $ hg show stack
    @  2737 commit 4
    o  d1a6 commit 3
    o  128c commit 2
    o  181c commit 1
    o  9f17 commit 0

Public parent of draft base is displayed, separated from stack

  $ hg phase --public -r 0
  $ hg show stack
    @  2737 commit 4
    o  d1a6 commit 3
    o  128c commit 2
    o  181c commit 1
   /   (stack base)
  o  9f17 commit 0

  $ hg phase --public -r 1
  $ hg show stack
    @  2737 commit 4
    o  d1a6 commit 3
    o  128c commit 2
   /   (stack base)
  o  181c commit 1

Draft descendants are shown

  $ hg -q up 2
  $ hg show stack
    o  2737 commit 4
    o  d1a6 commit 3
    @  128c commit 2
   /   (stack base)
  o  181c commit 1

  $ hg -q up 3
  $ hg show stack
    o  2737 commit 4
    @  d1a6 commit 3
    o  128c commit 2
   /   (stack base)
  o  181c commit 1

working dir on public changeset should display special message

  $ hg -q up 1
  $ hg show stack
  (empty stack; working directory parent is a published changeset)

Branch point in descendants displayed at top of graph

  $ hg -q up 3
  $ echo b > foo
  $ hg commit -m 'commit 5 (new dag branch)'
  created new head
  $ hg -q up 2
  $ hg show stack
   \ /  (multiple children)
    |
    o  d1a6 commit 3
    @  128c commit 2
   /   (stack base)
  o  181c commit 1

  $ cd ..

Base is stopped at merges

  $ hg init merge-base
  $ cd merge-base
  $ echo 0 > foo
  $ hg -q commit -A -m initial
  $ echo h1 > foo
  $ hg commit -m 'head 1'
  $ hg -q up 0
  $ echo h2 > foo
  $ hg -q commit -m 'head 2'
  $ hg phase --public -r 0:tip
  $ hg -q up 1
  $ hg merge -t :local 2
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m 'merge heads'

TODO doesn't yet handle case where wdir is a draft merge

  $ hg show stack
    @  8ee9 merge heads
   /   (stack base)
  o  5947 head 1

  $ echo d1 > foo
  $ hg commit -m 'draft 1'
  $ echo d2 > foo
  $ hg commit -m 'draft 2'

  $ hg show stack
    @  430d draft 2
    o  787b draft 1
   /   (stack base)
  o  8ee9 merge heads

  $ cd ..

Now move on to stacks when there are more commits after the base branchpoint

  $ hg init public-rebase
  $ cd public-rebase
  $ echo 0 > foo
  $ hg -q commit -A -m 'base'
  $ hg phase --public -r .
  $ echo d1 > foo
  $ hg commit -m 'draft 1'
  $ echo d2 > foo
  $ hg commit -m 'draft 2'
  $ hg -q up 0
  $ echo 1 > foo
  $ hg commit -m 'new 1'
  created new head
  $ echo 2 > foo
  $ hg commit -m 'new 2'
  $ hg -q up 2

Newer draft heads don't impact output

  $ hg show stack
    @  eaff draft 2
    o  2b21 draft 1
   /   (stack base)
  o  b66b base

Newer public heads are rendered

  $ hg phase --public -r '::tip'

  $ hg show stack
    o  baa4 new 2
   /    (2 commits ahead)
  :
  :    (stack head)
  : @  eaff draft 2
  : o  2b21 draft 1
  :/   (stack base)
  o  b66b base

If rebase is available, we show a hint how to rebase to that head

  $ hg --config extensions.rebase= show stack
    o  baa4 new 2
   /    (2 commits ahead; hg rebase --source 2b21 --dest baa4)
  :
  :    (stack head)
  : @  eaff draft 2
  : o  2b21 draft 1
  :/   (stack base)
  o  b66b base

Similar tests but for multiple heads

  $ hg -q up 0
  $ echo h2 > foo
  $ hg -q commit -m 'new head 2'
  $ hg phase --public -r .
  $ hg -q up 2

  $ hg show stack
    o  baa4 new 2
   /    (2 commits ahead)
  : o  9a84 new head 2
  :/    (1 commits ahead)
  :
  :    (stack head)
  : @  eaff draft 2
  : o  2b21 draft 1
  :/   (stack base)
  o  b66b base

  $ hg --config extensions.rebase= show stack
    o  baa4 new 2
   /    (2 commits ahead; hg rebase --source 2b21 --dest baa4)
  : o  9a84 new head 2
  :/    (1 commits ahead; hg rebase --source 2b21 --dest 9a84)
  :
  :    (stack head)
  : @  eaff draft 2
  : o  2b21 draft 1
  :/   (stack base)
  o  b66b base