view tests/test-convert-splicemap.t @ 33289:abd7dedbaa36

sparse: vendor Facebook-developed extension

Facebook has developed an extension to enable "sparse" checkouts -
a working directory with a subset of files. This feature is a critical
component in enabling repositories to scale to infinite number of
files while retaining reasonable performance. It's worth noting
that sparse checkout is only one possible solution to this problem:
another is virtual filesystems that realize files on first access.
But given that virtual filesystems may not be accessible to all
users, sparse checkout is necessary as a fallback.

Per mailing list discussion at
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/095868.html
we want to add sparse checkout to the Mercurial distribution via
roughly the following mechanism:

1. Vendor extension as-is with minimal modifications (this patch)
2. Refactor extension so it is more clearly experimental and inline
   with Mercurial practices
3. Move code from extension into core where possible
4. Drop experimental labeling and/or move feature into core
   after sign-off from narrow clone feature owners

This commit essentially copies the sparse extension and tests
from revision 71e0a2aeca92a4078fe1b8c76e32c88ff1929737 of the
https://bitbucket.org/facebook/hg-experimental repository.

A list of modifications made as part of vendoring is as follows:

* "EXPERIMENTAL" added to module docstring
* Imports were changed to match Mercurial style conventions
* "testedwith" value was updated to core Mercurial special value and
  comment boilerplate was inserted
* A "clone_sparse" function was renamed to "clonesparse" to appease
  the style checker
* Paths to the sparse extension in tests reflect built-in location
* test-sparse-extensions.t was renamed to test-sparse-fsmonitor.t
  and references to "simplecache" were removed. The test always skips
  because it isn't trivial to run it given the way we currently run
  fsmonitor tests
* A double empty line was removed from test-sparse-profiles.t

There are aspects of the added code that are obviously not ideal.
The goal is to make a minimal number of modifications as part of
the vendoring to make it easier to track changes from the original
implementation. Refactoring will occur in subsequent patches.

  $ 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]