tests/svn/svndump-move.sh

effectflag: store an empty effect flag for the moment

The idea behind effect flag is to store additional information in obs-markers
about what changed between a changeset and its successor(s). It's a low-level
information that comes without guarantees.

This information can be computed a posteriori, but only if we have all
changesets locally. This is not the case with distributed workflows where you
work with several people or on several computers (eg: laptop + build server).

Storing the effect-flag as a bitfield has several advantages:

- It's compact, we are using one byte per obs-marker at most for the effect-
  flag.
- It's compoundable, the obsfate log approach needs to display evolve history
  that could spans several obs-markers. Computing the effect-flag between a
  changeset and its grand-grand-grand-successor is simple thanks to the
  bitfield.

The effect-flag design has also some limitations:

- Evolving a changeset and reverting these changes just after would lead to
  two obs-markers with the same effect-flag without information that the first
  and third changesets are the same.

The effect-flag current design is a trade-off between compactness and
usefulness.

Storing this information helps commands to display a more complete and
understandable evolve history. For example, obslog (an Evolve command) use it
to improve its output:

x  62206adfd571 (34302) obscache: skip updating outdated obscache...
|    rewritten(parent) by Matthieu Laneuville <matthieu.laneuville@octobus...
|    rewritten(content) by Boris Feld <[e-mail]>

The effect flag is stored in obs-markers metadata while we iterate on the
information we want to store. We plan to extend the existing obsmarkers
bit-field when the effect flag design will be stabilized.

It's different from the CommitCustody concept, effect-flag are not signed and
can be forged. It's also different from the operation metadata as the command
name (for example: amend) could alter a changeset in different ways (changing
the content with hg amend, changing the description with hg amend -e, changing
the user with hg amend -U). Also it's compatible with every custom command
that writes obs-markers without needing to be updated.

The effect-flag is placed behind an experimental flag set to off by default.

Hook the saving of effect flag in create markers, but store only an empty one
for the moment, I will refine the values in effect flag in following patches.

For more information, see:

  https://www.mercurial-scm.org/wiki/ChangesetEvolutionDevel#Record_types_of_operation

Differential Revision: https://phab.mercurial-scm.org/D533

#!/bin/sh
#
# Use this script to generate move.svndump
#

mkdir temp
cd temp

mkdir project-orig
cd project-orig
mkdir trunk
echo a > trunk/a
mkdir trunk/d1
mkdir trunk/d2
echo b > trunk/d1/b
echo c > trunk/d1/c
echo d > trunk/d2/d
cd ..

svnadmin create svn-repo
svnurl=file://`pwd`/svn-repo
svn import project-orig $svnurl -m "init projA"

svn co $svnurl project
cd project
# Build a module renaming chain which used to confuse the converter.
# Update svn repository
echo a >> trunk/a
echo c >> trunk/d1/c
svn ci -m commitbeforemove
svn mv $svnurl/trunk $svnurl/subproject -m movedtrunk
svn up
mkdir subproject/trunk
svn add subproject/trunk
svn ci -m createtrunk
mkdir subproject/branches
svn add subproject/branches
svn ci -m createbranches
svn mv $svnurl/subproject/d1 $svnurl/subproject/trunk/d1 -m moved1
svn mv $svnurl/subproject/d2 $svnurl/subproject/trunk/d2 -m moved2
svn up
echo b >> subproject/trunk/d1/b

svn rm subproject/trunk/d2
svn ci -m "changeb and rm d2"
svn mv $svnurl/subproject/trunk/d1 $svnurl/subproject/branches/d1 -m moved1again

if svn help copy | grep 'SRC\[@REV\]' > /dev/null 2>&1; then
    # SVN >= 1.5 replaced the -r REV syntax with @REV
    # Copy a file from a past revision
    svn copy $svnurl/subproject/trunk/d2/d@7 $svnurl/subproject/trunk -m copyfilefrompast
    # Copy a directory from a past revision
    svn copy $svnurl/subproject/trunk/d2@7 $svnurl/subproject/trunk -m copydirfrompast
else
    # Copy a file from a past revision
    svn copy -r 7 $svnurl/subproject/trunk/d2/d $svnurl/subproject/trunk -m copyfilefrompast
    # Copy a directory from a past revision
    svn copy -r 7 $svnurl/subproject/trunk/d2 $svnurl/subproject/trunk -m copydirfrompast
fi

# Copy a directory while removing a subdirectory
svn up
mkdir -p subproject/trunk/d3/d31
echo e > subproject/trunk/d3/d31/e
echo f > subproject/trunk/d3/f
svn add subproject/trunk/d3
svn ci -m "add d3"
svn copy subproject/trunk/d3 subproject/trunk/d4
svn rm subproject/trunk/d3/d31
svn ci -m "copy dir and remove subdir"

# Test directory moves
svn up
mkdir -p subproject/trunk/d4old
echo g > subproject/trunk/d4old/g
svn add subproject/trunk/d4old
svn ci -m "add d4old"
svn mv subproject/trunk/d4old subproject/trunk/d4new
svn ci -m "rename d4old into d4new"

cd ..

svnadmin dump svn-repo > ../move.svndump