view tests/test-convert-tagsbranch-topology.t @ 27372:a79cba6cb206

help: add documentation for changegroup formats

There is no formal location for spec-like technical/internal docs. The
repository makes sense as such a location because spec-like
documentation should be reviewed (ruling out a wiki). mpm has also
stated that he would like this documentation to be part of the
built-in help system. So, we establish an "internals" sub-directory
to hold this class of documentation.

The format of changegroups does not appear to be documented anywhere,
even in source code. It therefore seemed like an appropriate first thing
to document.

This patch adds low-level documentation of versions 1 and 2 of the
changegroup foromat. It currently only describes the raw data format.
There is probably room to write higher-level documentation on strategies
for producing and consuming the data. We'll leave that for another day.

The added file is not yet accessible via `hg help` nor via hgweb.
Support for this will follow in subsequent patches.

#require git

  $ echo "[core]" >> $HOME/.gitconfig
  $ echo "autocrlf = false" >> $HOME/.gitconfig
  $ echo "[core]" >> $HOME/.gitconfig
  $ echo "autocrlf = false" >> $HOME/.gitconfig
  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > convert =
  > [convert]
  > hg.usebranchnames = True
  > hg.tagsbranch = tags-update
  > EOF
  $ GIT_AUTHOR_NAME='test'; export GIT_AUTHOR_NAME
  $ GIT_AUTHOR_EMAIL='[e-mail]'; export GIT_AUTHOR_EMAIL
  $ GIT_AUTHOR_DATE="2007-01-01 00:00:00 +0000"; export GIT_AUTHOR_DATE
  $ GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME"; export GIT_COMMITTER_NAME
  $ GIT_COMMITTER_EMAIL="$GIT_AUTHOR_EMAIL"; export GIT_COMMITTER_EMAIL
  $ GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"; export GIT_COMMITTER_DATE
  $ count=10
  $ action()
  > {
  >     GIT_AUTHOR_DATE="2007-01-01 00:00:$count +0000"
  >     GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"
  >     git "$@" >/dev/null 2>/dev/null || echo "git command error"
  >     count=`expr $count + 1`
  > }
  $ glog()
  > {
  >     hg log -G --template '{rev} "{desc|firstline}" files: {files}\n' "$@"
  > }
  $ convertrepo()
  > {
  >     hg convert --datesort git-repo hg-repo
  > }

Build a GIT repo with at least 1 tag

  $ mkdir git-repo
  $ cd git-repo
  $ git init >/dev/null 2>&1
  $ echo a > a
  $ git add a
  $ action commit -m "rev1"
  $ action tag -m "tag1" tag1
  $ cd ..

Convert without tags

  $ hg convert git-repo hg-repo --config convert.skiptags=True
  initializing destination hg-repo repository
  scanning source...
  sorting...
  converting...
  0 rev1
  updating bookmarks
  $ hg -R hg-repo tags
  tip                                0:d98c8ad3a4cf
  $ rm -rf hg-repo

Do a first conversion

  $ convertrepo
  initializing destination hg-repo repository
  scanning source...
  sorting...
  converting...
  0 rev1
  updating tags
  updating bookmarks

Simulate upstream  updates after first conversion

  $ cd git-repo
  $ echo b > a
  $ git add a
  $ action commit -m "rev2"
  $ action tag -m "tag2" tag2
  $ cd ..

Perform an incremental conversion

  $ convertrepo
  scanning source...
  sorting...
  converting...
  0 rev2
  updating tags
  updating bookmarks

Print the log

  $ cd hg-repo
  $ glog
  o  3 "update tags" files: .hgtags
  |
  | o  2 "rev2" files: a
  | |
  o |  1 "update tags" files: .hgtags
   /
  o  0 "rev1" files: a
  

  $ cd ..