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
$ cat >> $HGRCPATH << EOF
> [extensions]
> absorb=
> EOF
$ sedi() { # workaround check-code
> pattern="$1"
> shift
> for i in "$@"; do
> sed "$pattern" "$i" > "$i".tmp
> mv "$i".tmp "$i"
> done
> }
$ hg init repo1
$ cd repo1
Do not crash with empty repo:
$ hg absorb
abort: no mutable changeset to change
[255]
Make some commits:
$ for i in 1 2 3 4 5; do
> echo $i >> a
> hg commit -A a -m "commit $i" -q
> done
$ hg annotate a
0: 1
1: 2
2: 3
3: 4
4: 5
Change a few lines:
$ cat > a <<EOF
> 1a
> 2b
> 3
> 4d
> 5e
> EOF
Preview absorb changes:
$ hg absorb --print-changes --dry-run
showing changes for a
@@ -0,2 +0,2 @@
4ec16f8 -1
5c5f952 -2
4ec16f8 +1a
5c5f952 +2b
@@ -3,2 +3,2 @@
ad8b8b7 -4
4f55fa6 -5
ad8b8b7 +4d
4f55fa6 +5e
4 changesets affected
4f55fa6 commit 5
ad8b8b7 commit 4
5c5f952 commit 2
4ec16f8 commit 1
Run absorb:
$ hg absorb --apply-changes
saved backup bundle to * (glob)
2 of 2 chunk(s) applied
$ hg annotate a
0: 1a
1: 2b
2: 3
3: 4d
4: 5e
Delete a few lines and related commits will be removed if they will be empty:
$ cat > a <<EOF
> 2b
> 4d
> EOF
$ echo y | hg absorb --config ui.interactive=1
showing changes for a
@@ -0,1 +0,0 @@
f548282 -1a
@@ -2,1 +1,0 @@
ff5d556 -3
@@ -4,1 +2,0 @@
84e5416 -5e
3 changesets affected
84e5416 commit 5
ff5d556 commit 3
f548282 commit 1
apply changes (yn)? y
saved backup bundle to * (glob)
3 of 3 chunk(s) applied
$ hg annotate a
1: 2b
2: 4d
$ hg log -T '{rev} {desc}\n' -Gp
@ 2 commit 4
| diff -r 1cae118c7ed8 -r 58a62bade1c6 a
| --- a/a Thu Jan 01 00:00:00 1970 +0000
| +++ b/a Thu Jan 01 00:00:00 1970 +0000
| @@ -1,1 +1,2 @@
| 2b
| +4d
|
o 1 commit 2
| diff -r 84add69aeac0 -r 1cae118c7ed8 a
| --- a/a Thu Jan 01 00:00:00 1970 +0000
| +++ b/a Thu Jan 01 00:00:00 1970 +0000
| @@ -0,0 +1,1 @@
| +2b
|
o 0 commit 1
Non 1:1 map changes will be ignored:
$ echo 1 > a
$ hg absorb --apply-changes
nothing applied
[1]
The prompt is not given if there are no changes to be applied, even if there
are some changes that won't be applied:
$ hg absorb
showing changes for a
@@ -0,2 +0,1 @@
-2b
-4d
+1
0 changesets affected
nothing applied
[1]
Insertaions:
$ cat > a << EOF
> insert before 2b
> 2b
> 4d
> insert aftert 4d
> EOF
$ hg absorb -q --apply-changes
$ hg status
$ hg annotate a
1: insert before 2b
1: 2b
2: 4d
2: insert aftert 4d
Bookmarks are moved:
$ hg bookmark -r 1 b1
$ hg bookmark -r 2 b2
$ hg bookmark ba
$ hg bookmarks
b1 1:b35060a57a50
b2 2:946e4bc87915
* ba 2:946e4bc87915
$ sedi 's/insert/INSERT/' a
$ hg absorb -q --apply-changes
$ hg status
$ hg bookmarks
b1 1:a4183e9b3d31
b2 2:c9b20c925790
* ba 2:c9b20c925790
Non-modified files are ignored:
$ touch b
$ hg commit -A b -m b
$ touch c
$ hg add c
$ hg rm b
$ hg absorb --apply-changes
nothing applied
[1]
$ sedi 's/INSERT/Insert/' a
$ hg absorb --apply-changes
saved backup bundle to * (glob)
2 of 2 chunk(s) applied
$ hg status
A c
R b
Public commits will not be changed:
$ hg phase -p 1
$ sedi 's/Insert/insert/' a
$ hg absorb -pn
showing changes for a
@@ -0,1 +0,1 @@
-Insert before 2b
+insert before 2b
@@ -3,1 +3,1 @@
85b4e0e -Insert aftert 4d
85b4e0e +insert aftert 4d
1 changesets affected
85b4e0e commit 4
$ hg absorb --apply-changes
saved backup bundle to * (glob)
1 of 2 chunk(s) applied
$ hg diff -U 0
diff -r 1c8eadede62a a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a * (glob)
@@ -1,1 +1,1 @@
-Insert before 2b
+insert before 2b
$ hg annotate a
1: Insert before 2b
1: 2b
2: 4d
2: insert aftert 4d
$ hg co -qC 1
$ sedi 's/Insert/insert/' a
$ hg absorb --apply-changes
abort: no mutable changeset to change
[255]
Make working copy clean:
$ hg co -qC ba
$ rm c
$ hg status
Merge commit will not be changed:
$ echo 1 > m1
$ hg commit -A m1 -m m1
$ hg bookmark -q -i m1
$ hg update -q '.^'
$ echo 2 > m2
$ hg commit -q -A m2 -m m2
$ hg merge -q m1
$ hg commit -m merge
$ hg bookmark -d m1
$ hg log -G -T '{rev} {desc} {phase}\n'
@ 6 merge draft
|\
| o 5 m2 draft
| |
o | 4 m1 draft
|/
o 3 b draft
|
o 2 commit 4 draft
|
o 1 commit 2 public
|
o 0 commit 1 public
$ echo 2 >> m1
$ echo 2 >> m2
$ hg absorb --apply-changes
abort: cannot absorb into a merge
[255]
$ hg revert -q -C m1 m2
Use a new repo:
$ cd ..
$ hg init repo2
$ cd repo2
Make some commits to multiple files:
$ for f in a b; do
> for i in 1 2; do
> echo $f line $i >> $f
> hg commit -A $f -m "commit $f $i" -q
> done
> done
Use pattern to select files to be fixed up:
$ sedi 's/line/Line/' a b
$ hg status
M a
M b
$ hg absorb --apply-changes a
saved backup bundle to * (glob)
1 of 1 chunk(s) applied
$ hg status
M b
$ hg absorb --apply-changes --exclude b
nothing applied
[1]
$ hg absorb --apply-changes b
saved backup bundle to * (glob)
1 of 1 chunk(s) applied
$ hg status
$ cat a b
a Line 1
a Line 2
b Line 1
b Line 2
Test config option absorb.max-stack-size:
$ sedi 's/Line/line/' a b
$ hg log -T '{rev}:{node} {desc}\n'
3:712d16a8f445834e36145408eabc1d29df05ec09 commit b 2
2:74cfa6294160149d60adbf7582b99ce37a4597ec commit b 1
1:28f10dcf96158f84985358a2e5d5b3505ca69c22 commit a 2
0:f9a81da8dc53380ed91902e5b82c1b36255a4bd0 commit a 1
$ hg --config absorb.max-stack-size=1 absorb -pn
absorb: only the recent 1 changesets will be analysed
showing changes for a
@@ -0,2 +0,2 @@
-a Line 1
-a Line 2
+a line 1
+a line 2
showing changes for b
@@ -0,2 +0,2 @@
-b Line 1
712d16a -b Line 2
+b line 1
712d16a +b line 2
1 changesets affected
712d16a commit b 2
Test obsolete markers creation:
$ cat >> $HGRCPATH << EOF
> [experimental]
> evolution=createmarkers
> [absorb]
> add-noise=1
> EOF
$ hg --config absorb.max-stack-size=3 absorb -a
absorb: only the recent 3 changesets will be analysed
2 of 2 chunk(s) applied
$ hg log -T '{rev}:{node|short} {desc} {get(extras, "absorb_source")}\n'
6:3dfde4199b46 commit b 2 712d16a8f445834e36145408eabc1d29df05ec09
5:99cfab7da5ff commit b 1 74cfa6294160149d60adbf7582b99ce37a4597ec
4:fec2b3bd9e08 commit a 2 28f10dcf96158f84985358a2e5d5b3505ca69c22
0:f9a81da8dc53 commit a 1
$ hg absorb --apply-changes
1 of 1 chunk(s) applied
$ hg log -T '{rev}:{node|short} {desc} {get(extras, "absorb_source")}\n'
10:e1c8c1e030a4 commit b 2 3dfde4199b4610ea6e3c6fa9f5bdad8939d69524
9:816c30955758 commit b 1 99cfab7da5ffdaf3b9fc6643b14333e194d87f46
8:5867d584106b commit a 2 fec2b3bd9e0834b7cb6a564348a0058171aed811
7:8c76602baf10 commit a 1 f9a81da8dc53380ed91902e5b82c1b36255a4bd0
Executable files:
$ cat >> $HGRCPATH << EOF
> [diff]
> git=True
> EOF
$ cd ..
$ hg init repo3
$ cd repo3
#if execbit
$ echo > foo.py
$ chmod +x foo.py
$ hg add foo.py
$ hg commit -mfoo
#else
$ hg import -q --bypass - <<EOF
> # HG changeset patch
> foo
>
> diff --git a/foo.py b/foo.py
> new file mode 100755
> --- /dev/null
> +++ b/foo.py
> @@ -0,0 +1,1 @@
> +
> EOF
$ hg up -q
#endif
$ echo bla > foo.py
$ hg absorb --dry-run --print-changes
showing changes for foo.py
@@ -0,1 +0,1 @@
99b4ae7 -
99b4ae7 +bla
1 changesets affected
99b4ae7 foo
$ hg absorb --dry-run --interactive --print-changes
diff -r 99b4ae712f84 foo.py
1 hunks, 1 lines changed
examine changes to 'foo.py'?
(enter ? for help) [Ynesfdaq?] y
@@ -1,1 +1,1 @@
-
+bla
record this change to 'foo.py'?
(enter ? for help) [Ynesfdaq?] y
showing changes for foo.py
@@ -0,1 +0,1 @@
99b4ae7 -
99b4ae7 +bla
1 changesets affected
99b4ae7 foo
$ hg absorb --apply-changes
1 of 1 chunk(s) applied
$ hg diff -c .
diff --git a/foo.py b/foo.py
new file mode 100755
--- /dev/null
+++ b/foo.py
@@ -0,0 +1,1 @@
+bla
$ hg diff
Remove lines may delete changesets:
$ cd ..
$ hg init repo4
$ cd repo4
$ cat > a <<EOF
> 1
> 2
> EOF
$ hg commit -m a12 -A a
$ cat > b <<EOF
> 1
> 2
> EOF
$ hg commit -m b12 -A b
$ echo 3 >> b
$ hg commit -m b3
$ echo 4 >> b
$ hg commit -m b4
$ echo 1 > b
$ echo 3 >> a
$ hg absorb -pn
showing changes for a
@@ -2,0 +2,1 @@
bfafb49 +3
showing changes for b
@@ -1,3 +1,0 @@
1154859 -2
30970db -3
a393a58 -4
4 changesets affected
a393a58 b4
30970db b3
1154859 b12
bfafb49 a12
$ hg absorb -av | grep became
0:bfafb49242db: 1 file(s) changed, became 4:1a2de97fc652
1:115485984805: 2 file(s) changed, became 5:0c930dfab74c
2:30970dbf7b40: became empty and was dropped
3:a393a58b9a85: became empty and was dropped
$ hg log -T '{rev} {desc}\n' -Gp
@ 5 b12
| diff --git a/b b/b
| new file mode 100644
| --- /dev/null
| +++ b/b
| @@ -0,0 +1,1 @@
| +1
|
o 4 a12
diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,3 @@
+1
+2
+3
Use revert to make the current change and its parent disappear.
This should move us to the non-obsolete ancestor.
$ cd ..
$ hg init repo5
$ cd repo5
$ cat > a <<EOF
> 1
> 2
> EOF
$ hg commit -m a12 -A a
$ hg id
bfafb49242db tip
$ echo 3 >> a
$ hg commit -m a123 a
$ echo 4 >> a
$ hg commit -m a1234 a
$ hg id
82dbe7fd19f0 tip
$ hg revert -r 0 a
$ hg absorb -pn
showing changes for a
@@ -2,2 +2,0 @@
f1c23dd -3
82dbe7f -4
2 changesets affected
82dbe7f a1234
f1c23dd a123
$ hg absorb --apply-changes --verbose
1:f1c23dd5d08d: became empty and was dropped
2:82dbe7fd19f0: became empty and was dropped
a: 1 of 1 chunk(s) applied
$ hg id
bfafb49242db tip