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
Path conflict checking is currently disabled by default because of issue5716.
Turn it on for this test.
$ cat >> $HGRCPATH << EOF
> [experimental]
> merge.checkpathconflicts=True
> EOF
$ hg init repo
$ cd repo
$ echo base > base
$ hg add base
$ hg commit -m "base"
$ hg bookmark -i base
$ echo 1 > a
$ hg add a
$ hg commit -m "file"
$ hg bookmark -i file
$ echo 2 > a
$ hg commit -m "file2"
$ hg bookmark -i file2
$ hg up -q 0
$ mkdir a
$ echo 2 > a/b
$ hg add a/b
$ hg commit -m "dir"
created new head
$ hg bookmark -i dir
Basic merge - local file conflicts with remote directory
$ hg up -q file
$ hg bookmark -i
$ hg merge --verbose dir
resolving manifests
a: path conflict - a file or link has the same name as a directory
the local file has been renamed to a~853701544ac3
resolve manually then use 'hg resolve --mark a'
moving a to a~853701544ac3
getting a/b
1 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
[1]
$ hg update --clean .
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ rm a~853701544ac3
Basic update - local directory conflicts with remote file
$ hg up -q 0
$ mkdir a
$ echo 3 > a/b
$ hg up file
a: untracked directory conflicts with file
abort: untracked files in working directory differ from files in requested revision
[20]
$ hg up --clean file
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(activating bookmark file)
Repo state is ok
$ hg sum
parent: 1:853701544ac3
file
branch: default
bookmarks: *file
commit: (clean)
update: 2 new changesets (update)
phases: 4 draft
Basic update - untracked file conflicts with remote directory
$ hg up -q 0
$ echo untracked > a
$ hg up --config merge.checkunknown=warn dir
a: replacing untracked file
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(activating bookmark dir)
$ cat a.orig
untracked
$ rm -f a.orig
Basic clean update - local directory conflicts with changed remote file
$ hg up -q file
$ rm a
$ mkdir a
$ echo 4 > a/b
$ hg up file2
abort: *: *$TESTTMP/repo/a* (glob)
[255]
$ hg up --clean file2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(activating bookmark file2)
Repo state is ok
$ hg sum
parent: 2:f64e09fac717
file2
branch: default
bookmarks: *file2
commit: (clean)
update: 1 new changesets, 2 branch heads (merge)
phases: 4 draft