documentation: add some internals documentation about bid merge
This is an important algorithm that was only documented on the wiki so far.
Some update to the algorithm (and associated doc) is to expected in the future
since the bid merge algorithm is bug-ridden when it comes to file deletion comes
to play.
Differential Revision: https://phab.mercurial-scm.org/D8711
bundle w/o type option
$ hg init t1
$ hg init t2
$ cd t1
$ echo blablablablabla > file.txt
$ hg ci -Ama
adding file.txt
$ hg log | grep summary
summary: a
$ hg bundle ../b1 ../t2
searching for changes
1 changesets found
$ cd ../t2
$ hg unbundle ../b1
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets c35a0f9217e6 (1 drafts)
(run 'hg update' to get a working copy)
$ hg up
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg log | grep summary
summary: a
$ cd ..
Unknown compression type is rejected
$ hg init t3
$ cd t3
$ hg -q unbundle ../b1
$ hg bundle -a -t unknown out.hg
abort: unknown is not a recognized bundle specification
(see 'hg help bundlespec' for supported values for --type)
[255]
$ hg bundle -a -t unknown-v2 out.hg
abort: unknown compression is not supported
(see 'hg help bundlespec' for supported values for --type)
[255]
$ cd ..
test bundle types
$ testbundle() {
> echo % test bundle type $1
> hg init t$1
> cd t1
> hg bundle -t $1 ../b$1 ../t$1
> f -q -B6 -D ../b$1; echo
> cd ../t$1
> hg debugbundle ../b$1
> hg debugbundle --spec ../b$1
> echo
> cd ..
> }
$ for t in "None" "bzip2" "gzip" "none-v2" "v2" "v1" "gzip-v1"; do
> testbundle $t
> done
% test bundle type None
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
none-v2
% test bundle type bzip2
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
bzip2-v2
% test bundle type gzip
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {Compression: GZ}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
gzip-v2
% test bundle type none-v2
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
none-v2
% test bundle type v2
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {Compression: BZ}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
bzip2-v2
% test bundle type v1
searching for changes
1 changesets found
HG10BZ
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
bzip2-v1
% test bundle type gzip-v1
searching for changes
1 changesets found
HG10GZ
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
gzip-v1
Compression level can be adjusted for bundle2 bundles
$ hg init test-complevel
$ cd test-complevel
$ cat > file0 << EOF
> this is a file
> with some text
> and some more text
> and other content
> EOF
$ cat > file1 << EOF
> this is another file
> with some other content
> and repeated, repeated, repeated, repeated content
> EOF
$ hg -q commit -A -m initial
$ hg bundle -a -t gzip-v2 gzip-v2.hg
1 changesets found
$ f --size gzip-v2.hg
gzip-v2.hg: size=468
$ hg --config experimental.bundlecomplevel=1 bundle -a -t gzip-v2 gzip-v2-level1.hg
1 changesets found
$ f --size gzip-v2-level1.hg
gzip-v2-level1.hg: size=475
$ hg --config experimental.bundlecomplevel.gzip=1 --config experimental.bundlelevel=9 bundle -a -t gzip-v2 gzip-v2-level1.hg
1 changesets found
$ f --size gzip-v2-level1.hg
gzip-v2-level1.hg: size=475
$ cd ..
#if zstd
$ for t in "zstd" "zstd-v2"; do
> testbundle $t
> done
% test bundle type zstd
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {Compression: ZS}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
zstd-v2
% test bundle type zstd-v2
searching for changes
1 changesets found
HG20\x00\x00 (esc)
Stream params: {Compression: ZS}
changegroup -- {nbchanges: 1, version: 02} (mandatory: True)
c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
cache:rev-branch-cache -- {} (mandatory: False)
zstd-v2
Explicit request for zstd on non-generaldelta repos
$ hg --config format.usegeneraldelta=false init nogd
$ hg -q -R nogd pull t1
$ hg -R nogd bundle -a -t zstd nogd-zstd
1 changesets found
zstd-v1 always fails
$ hg -R tzstd bundle -a -t zstd-v1 zstd-v1
abort: compression engine zstd is not supported on v1 bundles
(see 'hg help bundlespec' for supported values for --type)
[255]
#else
zstd is a valid engine but isn't available
$ hg -R t1 bundle -a -t zstd irrelevant.hg
abort: compression engine zstd could not be loaded
[255]
#endif
test garbage file
$ echo garbage > bgarbage
$ hg init tgarbage
$ cd tgarbage
$ hg pull ../bgarbage
pulling from ../bgarbage
abort: ../bgarbage: not a Mercurial bundle
[255]
$ cd ..
test invalid bundle type
$ cd t1
$ hg bundle -a -t garbage ../bgarbage
abort: garbage is not a recognized bundle specification
(see 'hg help bundlespec' for supported values for --type)
[255]
$ cd ..