tests/test-convert-splicemap.t

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

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "convert=" >> $HGRCPATH
  $ glog()
  > {
  >     hg log -G --template '{rev}:{node|short} "{desc|firstline}"\
  >  files: {files}\n' "$@"
  > }
  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ echo b > b
  $ echo a >> a
  $ hg ci -Am addb
  adding b
  $ PARENTID1=`hg id --debug -i`
  $ echo c > c
  $ hg ci -Am addc
  adding c
  $ PARENTID2=`hg id --debug -i`
  $ cd ..
  $ glog -R repo1
  @  2:e55c719b85b6 "addc" files: c
  |
  o  1:6d4c2037ddc2 "addb" files: a b
  |
  o  0:07f494440405 "adda" files: a
  

  $ hg init repo2
  $ cd repo2
  $ echo b > a
  $ echo d > d
  $ hg ci -Am addaandd
  adding a
  adding d
  $ INVALIDID1=afd12345af
  $ INVALIDID2=28173x36ddd1e67bf7098d541130558ef5534a86
  $ CHILDID1=`hg id --debug -i`
  $ echo d >> d
  $ hg ci -Am changed
  $ CHILDID2=`hg id --debug -i`
  $ echo e > e
  $ hg ci -Am adde
  adding e
  $ cd ..
  $ glog -R repo2
  @  2:a39b65753b0a "adde" files: e
  |
  o  1:e4ea00df9189 "changed" files: d
  |
  o  0:527cdedf31fb "addaandd" files: a d
  

test invalid splicemap1

  $ cat > splicemap <<EOF
  > $CHILDID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: syntax error in splicemap(1): child parent1[,parent2] expected
  [255]

test invalid splicemap2

  $ cat > splicemap <<EOF
  > $CHILDID2 $PARENTID1, $PARENTID2, $PARENTID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: syntax error in splicemap(1): child parent1[,parent2] expected
  [255]

test invalid splicemap3

  $ cat > splicemap <<EOF
  > $INVALIDID1 $INVALIDID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: splicemap entry afd12345af is not a valid revision identifier
  [255]

splice repo2 on repo1

  $ cat > splicemap <<EOF
  > $CHILDID1 $PARENTID1
  > $CHILDID2 $PARENTID2,$CHILDID1
  > 
  > EOF
  $ cat splicemap
  527cdedf31fbd5ea708aa14eeecf53d4676f38db 6d4c2037ddc2cb2627ac3a244ecce35283268f8e
  e4ea00df91897da3079a10fab658c1eddba6617b e55c719b85b60e5102fac26110ba626e7cb6b7dc,527cdedf31fbd5ea708aa14eeecf53d4676f38db
  
  $ hg clone repo1 target1
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg convert --splicemap splicemap repo2 target1
  scanning source...
  sorting...
  converting...
  2 addaandd
  spliced in 6d4c2037ddc2cb2627ac3a244ecce35283268f8e as parents of 527cdedf31fbd5ea708aa14eeecf53d4676f38db
  1 changed
  spliced in e55c719b85b60e5102fac26110ba626e7cb6b7dc and 527cdedf31fbd5ea708aa14eeecf53d4676f38db as parents of e4ea00df91897da3079a10fab658c1eddba6617b
  0 adde
  $ glog -R target1
  o  5:16bc847b02aa "adde" files: e
  |
  o    4:e30e4fee3418 "changed" files: d
  |\
  | o  3:e673348c3a3c "addaandd" files: a d
  | |
  @ |  2:e55c719b85b6 "addc" files: c
  |/
  o  1:6d4c2037ddc2 "addb" files: a b
  |
  o  0:07f494440405 "adda" files: a
  



Test splicemap and conversion order

  $ hg init ordered
  $ cd ordered
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg branch branch
  marked working directory as branch branch
  (branches are permanent and global, did you want a bookmark?)
  $ echo a >> a
  $ hg ci -Am changea
  $ echo a >> a
  $ hg ci -Am changeaagain
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo b > b
  $ hg ci -Am addb
  adding b

We want 2 to depend on 1 and 3. Since 3 is always converted after 2,
the bug should be exhibited with all conversion orders.

  $ cat > ../splicemap <<EOF
  > `(hg id -r 2 -i --debug)` `(hg id -r 1 -i --debug)`, `(hg id -r 3 -i --debug)`
  > EOF
  $ cd ..
  $ cat splicemap
  7c364e7fa7d70ae525610c016317ed717b519d97 717d54d67e6c31fd75ffef2ff3042bdd98418437, 102a90ea7b4a3361e4082ed620918c261189a36a

Test regular conversion

  $ hg convert --splicemap splicemap ordered ordered-hg1
  initializing destination ordered-hg1 repository
  scanning source...
  sorting...
  converting...
  3 adda
  2 changea
  1 addb
  0 changeaagain
  spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
  $ glog -R ordered-hg1
  o    3:4cb04b9afbf2 "changeaagain" files: a
  |\
  | o  2:102a90ea7b4a "addb" files: b
  | |
  o |  1:717d54d67e6c "changea" files: a
  |/
  o  0:07f494440405 "adda" files: a
  

Test conversion with parent revisions already in dest, using source
and destination identifiers. Test unknown splicemap target.

  $ hg convert -r1 ordered ordered-hg2
  initializing destination ordered-hg2 repository
  scanning source...
  sorting...
  converting...
  1 adda
  0 changea
  $ hg convert -r3 ordered ordered-hg2
  scanning source...
  sorting...
  converting...
  0 addb
  $ cat > splicemap <<EOF
  > `(hg -R ordered id -r 2 -i --debug)` \
  > `(hg -R ordered-hg2 id -r 1 -i --debug)`,\
  > `(hg -R ordered-hg2 id -r 2 -i --debug)`
  > deadbeef102a90ea7b4a3361e4082ed620918c26 deadbeef102a90ea7b4a3361e4082ed620918c27
  > EOF
  $ hg convert --splicemap splicemap ordered ordered-hg2
  scanning source...
  splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
  sorting...
  converting...
  0 changeaagain
  spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
  $ glog -R ordered-hg2
  o    3:4cb04b9afbf2 "changeaagain" files: a
  |\
  | o  2:102a90ea7b4a "addb" files: b
  | |
  o |  1:717d54d67e6c "changea" files: a
  |/
  o  0:07f494440405 "adda" files: a
  

Test empty conversion

  $ hg convert --splicemap splicemap ordered ordered-hg2
  scanning source...
  splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
  sorting...
  converting...

Test clonebranches

  $ hg --config convert.hg.clonebranches=true convert \
  >   --splicemap splicemap ordered ordered-hg3
  initializing destination ordered-hg3 repository
  scanning source...
  abort: revision 717d54d67e6c31fd75ffef2ff3042bdd98418437 not found in destination repository (lookups with clonebranches=true are not implemented)
  [255]

Test invalid dependency

  $ cat > splicemap <<EOF
  > `(hg -R ordered id -r 2 -i --debug)` \
  > deadbeef102a90ea7b4a3361e4082ed620918c26,\
  > `(hg -R ordered-hg2 id -r 2 -i --debug)`
  > EOF
  $ hg convert --splicemap splicemap ordered ordered-hg4
  initializing destination ordered-hg4 repository
  scanning source...
  abort: unknown splice map parent: deadbeef102a90ea7b4a3361e4082ed620918c26
  [255]