view tests/test-sparse-clone.t @ 34179:036d47d7cf39

copytrace: move fast heuristic copytracing algorithm to core

copytrace extension in fb-hgext has a heuristic implementation of copy tracing
which is faster than the current copy tracing. The heuristic limits the search
of copies to just files that are either:

1) Renames in the same directory
2) Moved to other directory with same name

The default copytrace implementation is very slow as it finds all the new files
that were added from merge base up to the head commit and for each file it
checks whether it this was copied or moved version of a different file.

Stash@fb did analysis for the above heuristics on the fb repo and found that
among 2,443,768 moves/copies there are only 32,234 moves/copies which does not
fall under the above heuristics which is approx. 0.013 of total copies.

This patch moves the heuristics algorithm under config
`experimental.copytrace=heuristics`.

While moving fbext to core, this patch removes couple of less useful config
options named `sourcecommitlimit` and `maxmovescandidatestocheck`.

Tests are also added for the heuristics algorithm, which are basically copied
from fbext/tests/test-copytrace.t. The tests follow a pattern creating a server
repo and then cloning to a local repo to create public and draft changesets, the
distinction which will be useful in upcoming patches.

After this patch `experimental.copytrace` has the following behaviour:

1) `off`: turns off copytracing
2) `heuristics`: use the heuristic algorithm added in this patch.
3) everything else: use the full copytracing algorithm

.. feature::

   A new fast heuristic algorithm for copytracing which assumes that the files
   moves are either::
   1) Renames in the same directory
   2) Moves in other directories with same names
   You can use this algorithm by setting `experimental.copytrace=heuristics`.

Differential Revision: https://phab.mercurial-scm.org/D623

test sparse

  $ cat >> $HGRCPATH << EOF
  > [ui]
  > ssh = python "$RUNTESTDIR/dummyssh"
  > username = nobody <[e-mail]>
  > [extensions]
  > sparse=
  > purge=
  > strip=
  > rebase=
  > EOF

  $ hg init myrepo
  $ cd myrepo
  $ echo a > index.html
  $ echo x > data.py
  $ echo z > readme.txt
  $ cat > webpage.sparse <<EOF
  > [include]
  > *.html
  > EOF
  $ cat > backend.sparse <<EOF
  > [include]
  > *.py
  > EOF
  $ hg ci -Aqm 'initial'
  $ cd ..

Verify local clone with a sparse profile works

  $ hg clone --enable-profile webpage.sparse myrepo clone1
  updating to branch default
  warning: sparse profile 'webpage.sparse' not found in rev 000000000000 - ignoring it
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd clone1
  $ ls
  index.html
  $ cd ..

Verify local clone with include works

  $ hg clone --include *.sparse myrepo clone2
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd clone2
  $ ls
  backend.sparse
  webpage.sparse
  $ cd ..

Verify local clone with exclude works

  $ hg clone --exclude data.py myrepo clone3
  updating to branch default
  4 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd clone3
  $ ls
  backend.sparse
  index.html
  readme.txt
  webpage.sparse
  $ cd ..

Verify sparse clone profile over ssh works

  $ hg clone -q --enable-profile webpage.sparse ssh://user@dummy/myrepo clone4
  warning: sparse profile 'webpage.sparse' not found in rev 000000000000 - ignoring it
  $ cd clone4
  $ ls
  index.html
  $ cd ..