tests/test-git-interop.t

branchmap: skip obsolete revisions while computing heads

It's time to make this part of core Mercurial obsolescence-aware.

Not considering obsolete revisions when computing heads is clearly what
Mercurial should do. But there are a couple of small issues:

- Let's say tip of the repo is obsolete. There are two ways of finding tiprev
  for branchcache (both are in use): looking at input data for update() and
  looking at computed heads after update(). Previously, repo tip would be
  tiprev of the branchcache. With this patch, an obsolete revision can no
  longer be tiprev. And depending on what way we use for finding tiprev (input
  data vs computed heads) we'll get a different result. This is relevant when
  recomputing cache key from cache contents, and may lead to updating cache for
  obsolete revisions multiple times (not from scratch, because it still would
  be considered valid for a subset of revisions in the repo).

- If all commits on a branch are obsolete, the branchcache will include that
  branch, but the list of heads will be empty (that's why there's now `if not
  heads` when recomputing tiprev/tipnode from cache contents). Having an entry
  for every branch is currently required for notify extension (and
  test-notify.t to pass), because notify doesn't handle revsets in its
  subscription config very well and will throw an error if e.g. a branch
  doesn't exist.

- Cloning static HTTP repos may try to stat() a non-existent obsstore file. The
  issue is that we now care about obsolescence during clone, but statichttpvfs
  doesn't implement a stat method, so a regular vfs.stat() is used, and it
  assumes that file is local and calls os.stat().  During a clone, we're trying
  to stat() .hg/store/obsstore, but in static HTTP case we provide a literal
  URL to the obsstore file on the remote as if it were a local file path. On
  windows it actually results in a failure in test-static-http.t.

The first issue is going to be addressed in a series dedicated to making sure
branchcache is properly and timely written on disk (it wasn't perfect even
before this patch, but there aren't enough tests to demonstrate that). The
second issue will be addressed in a future patch for notify extension that will
make it not raise an exception if a branch doesn't exist. And the third one was
partially addressed in the previous patch in this series and will be properly
fixed in a future patch when this series is accepted.

filteredhash() grows a keyword argument to make sure that branchcache is also
invalidated when there are new obsolete revisions in its repo view. This way
the on-disk cache format is unchanged and compatible between versions (although
it will obviously be recomputed when switching versions before/after this patch
and the repo has obsolete revisions).

There's one test that uses plain `hg up` without arguments while updated to a
pruned commit. To make this test pass, simply return current working directory
parent. Later in this series this code will be replaced by what prune command
does: updating to the closest non-obsolete ancestor.

Test changes:

test-branch-change.t: update branch head and cache update message. The head of
default listed in hg heads is changed because revision 2 was rewritten as 7,
and 1 is the closest ancestor on the same branch, so it's the head of default
now.

The cache invalidation message appears now because of the cache hash change,
since we're now accounting for obsolete revisions. Here's some context:

"served.hidden" repo filter means everything is visible (no filtered
revisions), so before this series branch2-served.hidden file would not contain
any cache hash, only revnum and node. Now it also has a hash when there are
obsolete changesets in the repo. The command that the message appears for is
changing branch of 5 and 6, which are now obsolete, so the cache hash changes.

In general, when cache is simply out-of-date, it can be updated using the old
version as a base. But if cache hash differs, then the cache for that
particular repo filter is recomputed (at least with the current
implementation). This is what happens here.

test-obsmarker-template.t: the pull reports 2 heads changed, but after that the
repo correctly sees only 1. The new message could be better, but it's still an
improvement over the previous one where hg pull suggested merging with an
obsolete revision.

test-obsolete.t: we can see these revisions in hg log --hidden, but they
shouldn't be considered heads even with --hidden.

test-rebase-obsolete{,2}.t: there were new heads created previously after
making new orphan changesets, but they weren't detected. Now we are properly
detecting and reporting them.

test-rebase-obsolete4.t: there's only one head now because the other head is
pruned and was falsely reported before.

test-static-http.t: add obsstore to the list of requested files. This file
doesn't exist on the remotes, but clients want it anyway (they get 404). This
is fine, because there are other nonexistent files that clients request, like
.hg/bookmarks or .hg/cache/tags2-served.

Differential Revision: https://phab.mercurial-scm.org/D12097

#require pygit2 no-windows

Setup:
  $ GIT_AUTHOR_NAME='test'; export GIT_AUTHOR_NAME
  > GIT_AUTHOR_EMAIL='[e-mail]'; export GIT_AUTHOR_EMAIL
  > GIT_AUTHOR_DATE="2007-01-01 00:00:00 +0000"; export GIT_AUTHOR_DATE
  > GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME"; export GIT_COMMITTER_NAME
  > GIT_COMMITTER_EMAIL="$GIT_AUTHOR_EMAIL"; export GIT_COMMITTER_EMAIL
  > GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"; export GIT_COMMITTER_DATE
  > HGUSER="test <[e-mail]>"; export HGUSER
  > count=10
  > gitcommit() {
  >    GIT_AUTHOR_DATE="2007-01-01 00:00:$count +0000";
  >    GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"
  >    git commit "$@" >/dev/null 2>/dev/null || echo "git commit error"
  >    count=`expr $count + 1`
  >  }
  $ git config --global init.defaultBranch master


  $ hg version -v --config extensions.git= | grep '^[E ]'
  Enabled extensions:
    git  internal  (pygit2 *) (glob)

Test auto-loading extension works:
  $ mkdir nogit
  $ cd nogit
  $ mkdir .hg
  $ echo git >> .hg/requires
  $ hg status
  abort: repository specified git format in .hg/requires but has no .git directory
  [255]
  $ git config --global init.defaultBranch master
  $ git init
  Initialized empty Git repository in $TESTTMP/nogit/.git/
This status invocation shows some hg gunk because we didn't use
`hg init --git`, which fixes up .git/info/exclude for us.
  $ hg status
  ? .hg/cache/git-commits.sqlite
  ? .hg/cache/git-commits.sqlite-shm
  ? .hg/cache/git-commits.sqlite-wal
  ? .hg/requires
  $ cd ..

Now globally enable extension for the rest of the test:
  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > git=
  > [git]
  > log-index-cache-miss = yes
  > EOF

Test some edge cases around a commitless repo first
  $ mkdir empty
  $ cd empty
  $ git init
  Initialized empty Git repository in $TESTTMP/empty/.git/
  $ hg init --git
  $ hg heads
  [1]
  $ hg tip
  changeset:   -1:000000000000
  tag:         tip
  user:        
  date:        Thu Jan 01 00:00:00 1970 +0000
  
  $ cd ..

Make a new repo with git:
  $ mkdir foo
  $ cd foo
  $ git init
  Initialized empty Git repository in $TESTTMP/foo/.git/
Ignore the .hg directory within git:
  $ echo .hg >> .git/info/exclude
  $ echo alpha > alpha
  $ git add alpha
  $ gitcommit -am 'Add alpha'
  $ echo beta > beta
  $ git add beta
  $ gitcommit -am 'Add beta'
  $ echo gamma > gamma
  $ git status
  On branch master
  Untracked files:
    (use "git add <file>..." to include in what will be committed)
   (?)
  	gamma
  
  nothing added to commit but untracked files present (use "git add" to track)

Without creating the .hg, hg status fails:
  $ hg status
  abort: no repository found in '$TESTTMP/foo' (.hg not found)
  [10]
But if you run hg init --git, it works:
  $ hg init --git
  $ hg id --traceback
  heads mismatch, rebuilding dagcache
  3d9be8deba43 tip master
  $ hg status
  ? gamma
Log works too:
  $ hg log
  changeset:   1:3d9be8deba43
  bookmark:    master
  tag:         tip
  user:        test <[e-mail]>
  date:        Mon Jan 01 00:00:11 2007 +0000
  summary:     Add beta
  
  changeset:   0:c5864c9d16fb
  user:        test <[e-mail]>
  date:        Mon Jan 01 00:00:10 2007 +0000
  summary:     Add alpha
  


and bookmarks:
  $ hg bookmarks
   * master                    1:3d9be8deba43

diff even works transparently in both systems:
  $ echo blah >> alpha
  $ git diff
  diff --git a/alpha b/alpha
  index 4a58007..faed1b7 100644
  --- a/alpha
  +++ b/alpha
  @@ -1* +1,2 @@ (glob)
   alpha
  +blah
  $ hg diff --git
  diff --git a/alpha b/alpha
  --- a/alpha
  +++ b/alpha
  @@ -1,1 +1,2 @@
   alpha
  +blah

Remove a file, it shows as such:
  $ rm alpha
  $ hg status
  ! alpha
  ? gamma

Revert works:
  $ hg revert alpha --traceback
  $ hg status
  ? gamma
  $ git status
  On branch master
  Untracked files:
    (use "git add <file>..." to include in what will be committed)
   (?)
  	gamma
  
  nothing added to commit but untracked files present (use "git add" to track)

Add shows sanely in both:
  $ hg add gamma
  $ hg status
  A gamma
  $ hg files
  alpha
  beta
  gamma
  $ git ls-files
  alpha
  beta
  gamma
  $ git status
  On branch master
  Changes to be committed:
    (use "git restore --staged <file>..." to unstage) (?)
    (use "git reset HEAD <file>..." to unstage) (?)
   (?)
  	new file:   gamma
  

forget does what it should as well:
  $ hg forget gamma
  $ hg status
  ? gamma
  $ git status
  On branch master
  Untracked files:
    (use "git add <file>..." to include in what will be committed)
   (?)
  	gamma
  
  nothing added to commit but untracked files present (use "git add" to track)

clean up untracked file
  $ rm gamma

hg log FILE

  $ echo a >> alpha
  $ hg ci -m 'more alpha' --traceback --date '1583558723 18000'
  $ echo b >> beta
  $ hg ci -m 'more beta'
  heads mismatch, rebuilding dagcache
  $ echo a >> alpha
  $ hg ci -m 'even more alpha'
  heads mismatch, rebuilding dagcache
  $ hg log -G alpha
  heads mismatch, rebuilding dagcache
  @  changeset:   4:cf6ddf5d9b8a
  :  bookmark:    master
  :  tag:         tip
  :  user:        test <[e-mail]>
  :  date:        Thu Jan 01 00:00:00 1970 +0000
  :  summary:     even more alpha
  :
  o  changeset:   2:5b2c80b027ce
  :  user:        test <[e-mail]>
  :  date:        Sat Mar 07 00:25:23 2020 -0500
  :  summary:     more alpha
  :
  o  changeset:   0:c5864c9d16fb
     user:        test <[e-mail]>
     date:        Mon Jan 01 00:00:10 2007 +0000
     summary:     Add alpha
  
  $ hg log -G beta
  o  changeset:   3:980d4f79a9c6
  :  user:        test <[e-mail]>
  :  date:        Thu Jan 01 00:00:00 1970 +0000
  :  summary:     more beta
  :
  o  changeset:   1:3d9be8deba43
  |  user:        test <[e-mail]>
  ~  date:        Mon Jan 01 00:00:11 2007 +0000
     summary:     Add beta
  

  $ hg log -r "children(3d9be8deba43)" -T"{node|short} {children}\n"
  5b2c80b027ce 3:980d4f79a9c6

hg annotate

  $ hg annotate alpha
  0: alpha
  2: a
  4: a
  $ hg annotate beta
  1: beta
  3: b


Files in subdirectories. TODO: case-folding support, make this `A`
instead of `a`.

  $ mkdir a
  $ echo "This is file mu." > a/mu
  $ hg ci -A -m 'Introduce file a/mu'
  adding a/mu

Both hg and git agree a/mu is part of the repo

  $ git ls-files
  a/mu
  alpha
  beta
  $ hg files
  a/mu
  alpha
  beta

hg and git status both clean

  $ git status
  On branch master
  nothing to commit, working tree clean
  $ hg status
  heads mismatch, rebuilding dagcache


node|shortest works correctly
  $ hg log -T '{node}\n' | sort
  3d9be8deba43482be2c81a4cb4be1f10d85fa8bc
  5b2c80b027ce4250f88957326c199a2dc48dad60
  980d4f79a9c617d60d0fe1fb383753c4a61bea8e
  c1a41c49866ecc9c5411be932653e5b430961dd5
  c5864c9d16fb3431fe2c175ff84dc6accdbb2c18
  cf6ddf5d9b8a120bf90020342bcf7a96d0167279
  $ hg log -r c1a41c49866ecc9c5411be932653e5b430961dd5 --template "{shortest(node,1)}\n"
  c1

This covers gitlog._partialmatch()
  $ hg log -r c
  abort: ambiguous revision identifier: c
  [10]
  $ hg log -r c1
  changeset:   5:c1a41c49866e
  bookmark:    master
  tag:         tip
  user:        test <[e-mail]>
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Introduce file a/mu
  
  $ hg log -r dead
  abort: unknown revision 'dead'
  [255]

This coveres changelog.findmissing()
  $ hg merge --preview 3d9be8deba43

This covers manifest.diff()
  $ hg diff -c 3d9be8deba43
  diff -r c5864c9d16fb -r 3d9be8deba43 beta
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/beta	Mon Jan 01 00:00:11 2007 +0000
  @@ -0,0 +1,1 @@
  +beta


Interactive commit should work as expected

  $ echo bar >> alpha
  $ echo bar >> beta
  $ hg commit -m "test interactive commit" -i --config ui.interactive=true --config ui.interface=text << EOF
  > y
  > y
  > n
  > EOF
  diff --git a/alpha b/alpha
  1 hunks, 1 lines changed
  examine changes to 'alpha'?
  (enter ? for help) [Ynesfdaq?] y
  
  @@ -1,3 +1,4 @@
   alpha
   a
   a
  +bar
  record change 1/2 to 'alpha'?
  (enter ? for help) [Ynesfdaq?] y
  
  diff --git a/beta b/beta
  1 hunks, 1 lines changed
  examine changes to 'beta'?
  (enter ? for help) [Ynesfdaq?] n
  
Status should be consistent for both systems

  $ hg status
  heads mismatch, rebuilding dagcache
  M beta
  $ git status | egrep -v '^$|^  \(use '
  On branch master
  Changes not staged for commit:
  	modified:   beta
  no changes added to commit (use "git add" and/or "git commit -a")

Contents of each commit should be the same

  $ hg ex -r .
  # HG changeset patch
  # User test <[e-mail]>
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID 6024eda7986da123aa6797dd4603bd399d49bf5c
  # Parent  c1a41c49866ecc9c5411be932653e5b430961dd5
  test interactive commit
  
  diff -r c1a41c49866e -r 6024eda7986d alpha
  --- a/alpha	Thu Jan 01 00:00:00 1970 +0000
  +++ b/alpha	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,3 +1,4 @@
   alpha
   a
   a
  +bar
  $ git show
  commit 6024eda7986da123aa6797dd4603bd399d49bf5c
  Author: test <[e-mail]>
  Date:   Thu Jan 1 00:00:00 1970 +0000
  
      test interactive commit
  
  diff --git a/alpha b/alpha
  index d112a75..d2a2e9a 100644
  --- a/alpha
  +++ b/alpha
  @@ -1,3 +1,4 @@
   alpha
   a
   a
  +bar

Deleting files should also work (this was issue6398)
  $ hg revert -r . --all
  reverting beta
  $ hg rm beta
  $ hg ci -m 'remove beta'

This covers changelog.tiprev() (issue6510)
  $ hg log -r '(.^^):'
  heads mismatch, rebuilding dagcache
  changeset:   5:c1a41c49866e
  user:        test <[e-mail]>
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Introduce file a/mu
  
  changeset:   6:6024eda7986d
  user:        test <[e-mail]>
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     test interactive commit
  
  changeset:   7:1a0fee76bfc4
  bookmark:    master
  tag:         tip
  user:        test <[e-mail]>
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     remove beta
  
This covers changelog.headrevs() with a non-None arg
  $ hg log -r 'heads(.)' -Tcompact
  7[tip][master]   1a0fee76bfc4   1970-01-01 00:00 +0000   test
    remove beta