tests/test-stack.t

bookmark: add a test for a race condition on push

Bookmark pointing to unknown nodes are ignored. Later these ignored bookmarks
are dropped when writing the file back on disk. On paper, this behavior should
be fine, but with the current implementation, it can lead to unexpected
bookmark deletions.

In theory, to make sure writer as a consistent view, taking the lock also
invalidate bookmark data we already loaded into memory.  However this
invalidation is incomplete. The data are stored in a `filecache` that preserve
them if the bookmark related file are untouched. In practice, the bookmark data
in memory also depends of the changelog content, because of the step checking
if the bookmarks refers to a node known to the changelog. So if the bookmark
data were loaded from an up to date bookmark file but filtered with an outdated
changelog file this go undetected.

This condition is fairly specific, but can occurs very often in practice.  We
introduce a test recreating the situation. The test comes in an independant
changeset to show it actually reproduce the situation. The fix will come soon
after.

A large share of the initial investigation of this race condition was made by
Valentin Gatien-Baron <[e-mail]>.

This test test the low-level definition of stack, agnostic from all formatting

Initial setup

  $ cat << EOF >> $HGRCPATH
  > [ui]
  > logtemplate = {rev} {branch} {phase} {desc|firstline}\n
  > [extensions]
  > rebase=
  > [experimental]
  > evolution=createmarkers,exchange,allowunstable
  > EOF

  $ hg init main
  $ cd main
  $ hg branch other
  marked working directory as branch other
  (branches are permanent and global, did you want a bookmark?)
  $ echo aaa > aaa
  $ hg add aaa
  $ hg commit -m c_a
  $ echo aaa > bbb
  $ hg add bbb
  $ hg commit -m c_b
  $ hg branch foo
  marked working directory as branch foo
  $ echo aaa > ccc
  $ hg add ccc
  $ hg commit -m c_c
  $ echo aaa > ddd
  $ hg add ddd
  $ hg commit -m c_d
  $ echo aaa > eee
  $ hg add eee
  $ hg commit -m c_e
  $ echo aaa > fff
  $ hg add fff
  $ hg commit -m c_f
  $ hg log -G
  @  5 foo draft c_f
  |
  o  4 foo draft c_e
  |
  o  3 foo draft c_d
  |
  o  2 foo draft c_c
  |
  o  1 other draft c_b
  |
  o  0 other draft c_a
  

Check that stack doesn't include public changesets
--------------------------------------------------

  $ hg up other
  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
  $ hg log -G -r "stack()"
  @  1 other draft c_b
  |
  o  0 other draft c_a
  
  $ hg phase --public 'branch("other")'
  $ hg log -G -r "stack()"
  $ hg up foo
  4 files updated, 0 files merged, 0 files removed, 0 files unresolved

Simple test
-----------

'stack()' list all changeset in the branch

  $ hg branch
  foo
  $ hg log -G -r "stack()"
  @  5 foo draft c_f
  |
  o  4 foo draft c_e
  |
  o  3 foo draft c_d
  |
  o  2 foo draft c_c
  |
  ~

Case with some of the branch unstable
------------------------------------

  $ hg up 3
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo bbb > ddd
  $ hg commit --amend
  2 new orphan changesets
  $ hg log -G
  @  6 foo draft c_d
  |
  | *  5 foo draft c_f
  | |
  | *  4 foo draft c_e
  | |
  | x  3 foo draft c_d
  |/
  o  2 foo draft c_c
  |
  o  1 other public c_b
  |
  o  0 other public c_a
  
  $ hg log -G -r "stack()"
  @  6 foo draft c_d
  |
  ~
  $ hg up -r "desc(c_e)"
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg log -G -r "stack()"
  @  4 foo draft c_e
  |
  x  3 foo draft c_d
  |
  ~
  $ hg up -r "desc(c_d)"
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ hg log -G -r "stack()"
  @  6 foo draft c_d
  |
  ~

Case with multiple topological heads
------------------------------------

Make things linear again

  $ hg rebase -s 'desc(c_e)' -d 'desc(c_d) - obsolete()'
  rebasing 4:4f2a69f6d380 "c_e"
  rebasing 5:913c298d8b0a "c_f"
  $ hg log -G
  o  8 foo draft c_f
  |
  o  7 foo draft c_e
  |
  @  6 foo draft c_d
  |
  o  2 foo draft c_c
  |
  o  1 other public c_b
  |
  o  0 other public c_a
  

Create the second branch

  $ hg up 'desc(c_d)'
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo aaa > ggg
  $ hg add ggg
  $ hg commit -m c_g
  created new head
  $ echo aaa > hhh
  $ hg add hhh
  $ hg commit -m c_h
  $ hg log -G
  @  10 foo draft c_h
  |
  o  9 foo draft c_g
  |
  | o  8 foo draft c_f
  | |
  | o  7 foo draft c_e
  |/
  o  6 foo draft c_d
  |
  o  2 foo draft c_c
  |
  o  1 other public c_b
  |
  o  0 other public c_a
  

Test output

  $ hg log -G -r "stack(10)"
  @  10 foo draft c_h
  |
  o  9 foo draft c_g
  |
  ~
  $ hg log -G -r "stack(8)"
  o  8 foo draft c_f
  |
  o  7 foo draft c_e
  |
  ~
  $ hg log -G -r "stack(head())"
  @  10 foo draft c_h
  |
  o  9 foo draft c_g
  |
  ~
  o  8 foo draft c_f
  |
  o  7 foo draft c_e
  |
  ~
Check the stack order
  $ hg log -r "first(stack())"
  9 foo draft c_g
  $ hg log -r "first(stack(10))"
  9 foo draft c_g
  $ hg log -r "first(stack(8))"
  7 foo draft c_e
  $ hg log -r "first(stack(head()))"
  7 foo draft c_e

Case with multiple heads with unstability involved
--------------------------------------------------

We amend the message to make sure the display base pick the right changeset

  $ hg up 'desc(c_d)'
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo ccc > ddd
  $ hg commit --amend -m 'c_D'
  4 new orphan changesets
  $ hg rebase -d . -s 'desc(c_g)'
  rebasing 9:2ebb6e48ab8a "c_g"
  rebasing 10:634f38e27a1d "c_h"
  $ hg log -G
  o  13 foo draft c_h
  |
  o  12 foo draft c_g
  |
  @  11 foo draft c_D
  |
  | *  8 foo draft c_f
  | |
  | *  7 foo draft c_e
  | |
  | x  6 foo draft c_d
  |/
  o  2 foo draft c_c
  |
  o  1 other public c_b
  |
  o  0 other public c_a
  

We should improve stack definition to also show 12 and 13 here
  $ hg log -G -r "stack()"
  @  11 foo draft c_D
  |
  ~