rust-nodemap: accounting for dead blocks
By the very append-only nature of the `NodeTree`, inserting
new blocks has the effect of making some of the older ones
useless as they become unreachable.
Therefore some automatic housekeeping will need to be provided.
This is standard procedure in the word of databases, under names
such as "repack" or "vacuum".
The new `masked_readonly_blocks()` will provide callers with
useful information to decide if the nodetree is ripe for
repacking, but all the `NodeTree` can provide is how many
blocks have been masked in the currently mutable part. Analysing
the readonly part would be way too long to do it for each
transaction and defeat the whole purpose of nodemap persistence.
Serializing callers (from the Python layer) will get this figure
before each extraction and maintain an aggregate counter of
unreachable blocks separately.
Note: at this point, the most efficient repacking is just to restart
afresh with a full rescan.
Differential Revision: https://phab.mercurial-scm.org/D8097
$ HGMERGE=true; export HGMERGE
$ hg init r1
$ cd r1
$ echo a > a
$ hg addremove
adding a
$ hg commit -m "1"
$ hg clone . ../r2
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../r2
$ hg up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo abc > a
$ hg diff --nodates
diff -r c19d34741b0a a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a
+abc
$ cd ../r1
$ echo b > b
$ echo a2 > a
$ hg addremove
adding b
$ hg commit -m "2"
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
preserving a for resolve of a
b: remote created -> g
getting b
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up 0
starting 4 threads for background file closing (?)
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 1e71731e6fbb, local: 1e71731e6fbb+, remote: c19d34741b0a
preserving a for resolve of a
b: other deleted -> r
removing b
starting 4 threads for background file closing (?)
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
0 files updated, 1 files merged, 1 files removed, 0 files unresolved
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
preserving a for resolve of a
b: remote created -> g
getting b
a: versions differ -> m (premerge)
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
a: versions differ -> m (merge)
picked tool 'true' for a (binary False symlink False changedelete False)
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg -v history
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a b
description:
2
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a
description:
1
$ hg diff --nodates
diff -r 1e71731e6fbb a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a2
+abc
create a second head
$ cd ../r1
$ hg up 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo b2 > b
$ echo a3 > a
$ hg addremove
adding b
$ hg commit -m "3"
created new head
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 1:1e71731e6fbb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
updated to "1e71731e6fbb: 2"
1 other heads for branch "default"
test conflicting untracked files
$ hg up -qC 0
$ echo untracked > b
$ hg st
? b
$ hg up 1
b: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
$ rm b
test conflicting untracked ignored file
$ hg up -qC 0
$ echo ignored > .hgignore
$ hg add .hgignore
$ hg ci -m 'add .hgignore'
created new head
$ echo ignored > ignored
$ hg add ignored
$ hg ci -m 'add ignored file'
$ hg up -q 'desc("add .hgignore")'
$ echo untracked > ignored
$ hg st
$ hg up 'desc("add ignored file")'
ignored: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
test a local add
$ cd ..
$ hg init a
$ hg init b
$ echo a > a/a
$ echo a > b/a
$ hg --cwd a commit -A -m a
adding a
$ cd b
$ hg add a
$ hg pull -u ../a
pulling from ../a
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets cb9a9f314b8b
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
test updating backwards through a rename
$ hg mv a b
$ hg ci -m b
$ echo b > b
$ hg up -q 0
$ hg st
M a
$ hg diff --nodates
diff -r cb9a9f314b8b a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a
+b
test for superfluous filemerge of clean files renamed in the past
$ hg up -qC tip
$ echo c > c
$ hg add c
$ hg up -qt:fail 0
$ cd ..