bundle2: implement consume() API on unbundlepart
We want bundle parts to not be seekable by default. That means
eliminating the generic seek() method.
A common pattern in bundle2.py is to seek to the end of the part
data. This is mainly used by the part iteration code to ensure
the underlying stream is advanced to the next bundle part.
In this commit, we establish a dedicated API for consuming a
bundle2 part data. We switch users of seek() to it.
The old implementation of seek(0, os.SEEK_END) would effectively
call self.read(). The new implementation calls self.read(32768)
in a loop. The old implementation would therefore assemble a
buffer to hold all remaining data being seeked over. For seeking
over large bundle parts, this would involve a large allocation and
a lot of overhead to collect intermediate data! This overhead can
be seen in the results for `hg perfbundleread`:
! bundle2 iterparts()
! wall 10.891305 comb 10.820000 user 7.990000 sys 2.830000 (best of 3)
! wall 8.070791 comb 8.060000 user 7.180000 sys 0.880000 (best of 3)
! bundle2 part seek()
! wall 12.991478 comb 10.390000 user 7.720000 sys 2.670000 (best of 3)
! wall 10.370142 comb 10.350000 user 7.430000 sys 2.920000 (best of 3)
Of course, skipping over large payload data isn't likely very common.
So I doubt the performance wins will be observed in the wild.
Differential Revision: https://phab.mercurial-scm.org/D1388
#require bzr
$ . "$TESTDIR/bzr-definitions"
empty directory
$ mkdir test-empty
$ cd test-empty
$ bzr init -q source
$ cd source
$ echo content > a
$ bzr add -q a
$ bzr commit -q -m 'Initial add'
$ mkdir empty
$ bzr add -q empty
$ bzr commit -q -m 'Empty directory added'
$ echo content > empty/something
$ bzr add -q empty/something
$ bzr commit -q -m 'Added file into directory'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
2 Initial add
1 Empty directory added
0 Added file into directory
$ manifest source-hg 1
% manifest of 1
644 a
$ manifest source-hg tip
% manifest of tip
644 a
644 empty/something
$ cd ..
directory renames
$ mkdir test-dir-rename
$ cd test-dir-rename
$ bzr init -q source
$ cd source
$ mkdir tpyo
$ echo content > tpyo/something
$ bzr add -q tpyo
$ bzr commit -q -m 'Added directory'
$ bzr mv tpyo typo
tpyo => typo
$ bzr commit -q -m 'Oops, typo'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Added directory
0 Oops, typo
$ manifest source-hg 0
% manifest of 0
644 tpyo/something
$ manifest source-hg tip
% manifest of tip
644 typo/something
$ cd ..
nested directory renames
$ mkdir test-nested-dir-rename
$ cd test-nested-dir-rename
$ bzr init -q source
$ cd source
$ mkdir -p firstlevel/secondlevel/thirdlevel
$ echo content > firstlevel/secondlevel/file
$ echo this_needs_to_be_there_too > firstlevel/secondlevel/thirdlevel/stuff
$ bzr add -q firstlevel
$ bzr commit -q -m 'Added nested directories'
$ bzr mv firstlevel/secondlevel secondlevel
firstlevel/secondlevel => secondlevel
$ bzr commit -q -m 'Moved secondlevel one level up'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Added nested directories
0 Moved secondlevel one level up
$ manifest source-hg tip
% manifest of tip
644 secondlevel/file
644 secondlevel/thirdlevel/stuff
$ cd ..
directory remove
$ mkdir test-dir-remove
$ cd test-dir-remove
$ bzr init -q source
$ cd source
$ mkdir src
$ echo content > src/sourcecode
$ bzr add -q src
$ bzr commit -q -m 'Added directory'
$ bzr rm -q src
$ bzr commit -q -m 'Removed directory'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Added directory
0 Removed directory
$ manifest source-hg 0
% manifest of 0
644 src/sourcecode
$ manifest source-hg tip
% manifest of tip
$ cd ..
directory replace
$ mkdir test-dir-replace
$ cd test-dir-replace
$ bzr init -q source
$ cd source
$ mkdir first second
$ echo content > first/file
$ echo morecontent > first/dummy
$ echo othercontent > second/something
$ bzr add -q first second
$ bzr commit -q -m 'Initial layout'
$ bzr mv first/file second/file
first/file => second/file
$ bzr mv first third
first => third
$ bzr commit -q -m 'Some conflicting moves'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Initial layout
0 Some conflicting moves
$ manifest source-hg tip
% manifest of tip
644 second/file
644 second/something
644 third/dummy
$ cd ..
divergent nested renames (issue3089)
$ mkdir test-divergent-renames
$ cd test-divergent-renames
$ bzr init -q source
$ cd source
$ mkdir -p a/c
$ echo a > a/fa
$ echo c > a/c/fc
$ bzr add -q a
$ bzr commit -q -m 'Initial layout'
$ bzr mv a b
a => b
$ mkdir a
$ bzr add a
add(ed|ing) a (re)
$ bzr mv b/c a/c
b/c => a/c
$ bzr status
added:
a/
renamed:
a/? => b/? (re)
a/c/? => a/c/? (re)
$ bzr commit -q -m 'Divergent renames'
$ cd ..
$ hg convert source source-hg
initializing destination source-hg repository
scanning source...
sorting...
converting...
1 Initial layout
0 Divergent renames
$ hg -R source-hg st -C --change 1
A b/fa
a/fa
R a/fa
$ hg -R source-hg manifest -r 1
a/c/fc
b/fa
$ cd ..