dirstate-tree: Add tree traversal/iteration
Like Python’s, Rust’s iterators are "external" in that they are driven
by a caller who calls a `next` method. This is as opposed to "internal"
iterators who drive themselves and call a callback for each item.
Writing an internal iterator traversing a tree is easy with recursion,
but internal iterators cannot rely on the call stack in that way,
they must save in an explicit object all state that they need to be
preserved across two `next` calls.
This algorithm uses a `Vec` as a stack that contains what would be
local variables on the call stack if we could use recursion.
Differential Revision: https://phab.mercurial-scm.org/D10370
====================================
Testing head checking code: Case B-2
====================================
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
This case is part of a series of tests checking this behavior.
Category B: simple case involving pruned changesets
TestCase 2: multi-changeset branch, head is pruned, rest is superceeded, through other
.. old-state:
..
.. * 2 changeset branch
..
.. new-state:
..
.. * old head is rewritten then pruned
.. * 1 new branch succeeding to the other changeset in the old branch (through another obsolete branch)
..
.. expected-result:
..
.. * push allowed
..
.. graph-summary:
..
.. B ø⇠⊗ B'
.. | | A'
.. A ø⇠ø⇠◔ A''
.. |/ /
.. | /
.. |/
.. ●
$ . $TESTDIR/testlib/push-checkheads-util.sh
Test setup
----------
$ mkdir B8
$ cd B8
$ setuprepos
creating basic server and client repo
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd server
$ mkcommit B0
$ cd ../client
$ hg pull
pulling from $TESTTMP/B8/server
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets d73caddc5533 (1 drafts)
(run 'hg update' to get a working copy)
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit A1
created new head
$ mkcommit B1
$ hg up 0
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ mkcommit A2
created new head
$ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`
1 new obsolescence markers
obsoleted 1 changesets
1 new orphan changesets
$ hg debugobsolete `getid "desc(B0)" ` `getid "desc(B1)"`
1 new obsolescence markers
obsoleted 1 changesets
$ hg debugobsolete --record-parents `getid "desc(B1)"`
1 new obsolescence markers
obsoleted 1 changesets
$ hg debugobsolete `getid "desc(A1)" ` `getid "desc(A2)"`
1 new obsolescence markers
obsoleted 1 changesets
$ hg log -G --hidden
@ c1f8d089020f (draft): A2
|
| x 262c8c798096 (draft): B1
| |
| x f6082bc4ffef (draft): A1
|/
| x d73caddc5533 (draft): B0
| |
| x 8aaa48160adc (draft): A0
|/
o 1e4be0697311 (public): root
Actual testing
--------------
$ hg push
pushing to $TESTTMP/B8/server
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
4 new obsolescence markers
obsoleted 2 changesets
$ cd ../..