git-svn 1.5.3 does not understand grafts?

git-svn 1.5.3 does not understand grafts?

[Joakim Tjernlund]

svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"

In my git repo I do
git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
git-svn fetch
git branch svn remotes/git-svn
#make remotes/git-svn parent to the initial commit in my git tree
graftid=`git-show-ref -s svn`
echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
#da783... is the initial commit in my git tree.
git-svn dcommit

fails with:
Committing to file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
Commit da783cce390ce013b19f1d308ea6813269c6a6b5
has no parent commit, and therefore nothing to diff against.
You should be working from a repository originally created by git-svn


 Jocke

Re: git-svn 1.5.3 does not understand grafts?

[Joakim Tjernlund]

On Fri, 2007-09-07 at 18:41 +0200, Joakim Tjernlund wrote:
> svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
> svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
> svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"
> 
> In my git repo I do
> git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> git-svn fetch
> git branch svn remotes/git-svn
> #make remotes/git-svn parent to the initial commit in my git tree
> graftid=`git-show-ref -s svn`
> echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
> #da783... is the initial commit in my git tree.
> git-svn dcommit
> 
> fails with:
> Committing to file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
> Commit da783cce390ce013b19f1d308ea6813269c6a6b5
> has no parent commit, and therefore nothing to diff against.
> You should be working from a repository originally created by git-svn
> 
> 
>  Jocke

Using filter-branch helps, but git-svn isn't too happy:

git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
git-svn fetch
git branch svn remotes/git-svn
#make remotes/git-svn parent to the initial commit in my git tree
graftid=`git-show-ref -s svn`
echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
#da783... is the initial commit in my git tree.
git filter-branch $graftid..HEAD
git-svn dcommit

Now I get alot of complaints, but it commits to svn.
It takes forever though:
r3 = 55a489bd4f66dd1f641a4676359d7b8911dc7d83 (git-svn)
W: HEAD and refs/remotes/git-svn differ, using rebase:
:100644 100644 f85ae11af7715a224015582724cb2bab87ec914a
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84eba702cce3a9e4f125162f77f3ea52ae45aebc
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890dfe7abdac0aa03eeca24572d98e3953db69d7
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100644 3095638b3f28d5b8e04be1c660fc37bf82e034c2
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2967bc6e21ab9581a47266966867ded04d8076f1
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aa86ba2a2c313ca688700e75a4353a4d66846b54
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853c18b6c42f9d463f14eede3b84ed700b00dcd5 M    transceiver.cFirst,
rewinding head to replay your work on top of it...
HEAD is now at 55a489b... Initial import of 7700, sws100034.

I get alot similar messages until it is finished.

    Jocke 

Re: git-svn 1.5.3 does not understand grafts?

[Joakim Tjernlund]

On Fri, 2007-09-07 at 18:52 +0200, Joakim Tjernlund wrote:
> On Fri, 2007-09-07 at 18:41 +0200, Joakim Tjernlund wrote:
> > svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
> > svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
> > svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"
> > 
> > In my git repo I do
> > git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > git-svn fetch
> > git branch svn remotes/git-svn
> > #make remotes/git-svn parent to the initial commit in my git tree
> > graftid=`git-show-ref -s svn`
> > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
> > #da783... is the initial commit in my git tree.
> > git-svn dcommit
> > 
> > fails with:
> > Committing to file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
> > Commit da783cce390ce013b19f1d308ea6813269c6a6b5
> > has no parent commit, and therefore nothing to diff against.
> > You should be working from a repository originally created by git-svn
> > 
> > 
> >  Jocke
> 
> Using filter-branch helps, but git-svn isn't too happy:
> 
> git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> git-svn fetch
> git branch svn remotes/git-svn
> #make remotes/git-svn parent to the initial commit in my git tree
> graftid=`git-show-ref -s svn`
> echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
> #da783... is the initial commit in my git tree.
> git filter-branch $graftid..HEAD
> git-svn dcommit
> 
> Now I get alot of complaints, but it commits to svn.
> It takes forever though:
> r3 = 55a489bd4f66dd1f641a4676359d7b8911dc7d83 (git-svn)
> W: HEAD and refs/remotes/git-svn differ, using rebase:
> :100644 100644 f85ae11af7715a224015582724cb2bab87ec914a
[SNIP]

Just wanted to add that 1.5.2.2 works with grafts and 
that I suspect sub read_commit_parents in git-svn, but as I don't
do perl I am stuck.

     Jocke
Oh, Eric W. CC:ed as well this time

Re: git-svn 1.5.3 does not understand grafts?

[Eric Wong]

Joakim Tjernlund <joakim.tjernlund@transmode.se> wrote:
> On Fri, 2007-09-07 at 18:52 +0200, Joakim Tjernlund wrote:
> > On Fri, 2007-09-07 at 18:41 +0200, Joakim Tjernlund wrote:
> > > svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
> > > svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
> > > svn mkdir  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"
> > > 
> > > In my git repo I do
> > > git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > > git-svn fetch
> > > git branch svn remotes/git-svn
> > > #make remotes/git-svn parent to the initial commit in my git tree
> > > graftid=`git-show-ref -s svn`
> > > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
> > > #da783... is the initial commit in my git tree.
> > > git-svn dcommit
> > > 
> > > fails with:
> > > Committing to file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
> > > Commit da783cce390ce013b19f1d308ea6813269c6a6b5
> > > has no parent commit, and therefore nothing to diff against.
> > > You should be working from a repository originally created by git-svn
> > 
> > Using filter-branch helps, but git-svn isn't too happy:
> > 
> > git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > git-svn fetch
> > git branch svn remotes/git-svn
> > #make remotes/git-svn parent to the initial commit in my git tree
> > graftid=`git-show-ref -s svn`
> > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts
> > #da783... is the initial commit in my git tree.
> > git filter-branch $graftid..HEAD
> > git-svn dcommit
> > 
> > Now I get alot of complaints, but it commits to svn.
> > It takes forever though:
> > r3 = 55a489bd4f66dd1f641a4676359d7b8911dc7d83 (git-svn)
> > W: HEAD and refs/remotes/git-svn differ, using rebase:
> > :100644 100644 f85ae11af7715a224015582724cb2bab87ec914a

I haven't used filter-branch myself, but you probably need to remove all
.rev_db* files in $GIT_DIR after running it (git-svn can recreate them
unless you use the svmRevProps or noMetadata options.

> [SNIP]
> 
> Just wanted to add that 1.5.2.2 works with grafts and 
> that I suspect sub read_commit_parents in git-svn, but as I don't
> do perl I am stuck.

Crap, it looks like I completely forgot about the existence
of grafts while doing this function.

>      Jocke
> Oh, Eric W. CC:ed as well this time

Thanks.

-- 
Eric Wong

RE: git-svn 1.5.3 does not understand grafts?

[Joakim Tjernlund]

> -----Original Message-----
> From: Eric Wong [mailto:normalperson@yhbt.net] 
> Sent: den 8 september 2007 07:02
> To: Joakim Tjernlund
> Cc: git
> Subject: Re: git-svn 1.5.3 does not understand grafts?
> 
> Joakim Tjernlund <joakim.tjernlund@transmode.se> wrote:
> > On Fri, 2007-09-07 at 18:52 +0200, Joakim Tjernlund wrote:
> > > On Fri, 2007-09-07 at 18:41 +0200, Joakim Tjernlund wrote:
> > > > svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
> > > > svn mkdir  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
> > > > svn mkdir  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"
> > > > 
> > > > In my git repo I do
> > > > git-svn init  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > > > git-svn fetch
> > > > git branch svn remotes/git-svn
> > > > #make remotes/git-svn parent to the initial commit in 
> my git tree
> > > > graftid=`git-show-ref -s svn`
> > > > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid 
> > .git/info/grafts
> > > > #da783... is the initial commit in my git tree.
> > > > git-svn dcommit
> > > > 
> > > > fails with:
> > > > Committing to 
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
> > > > Commit da783cce390ce013b19f1d308ea6813269c6a6b5
> > > > has no parent commit, and therefore nothing to diff against.
> > > > You should be working from a repository originally 
> created by git-svn
> > > 
> > > Using filter-branch helps, but git-svn isn't too happy:
> > > 
> > > git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > > git-svn fetch
> > > git branch svn remotes/git-svn
> > > #make remotes/git-svn parent to the initial commit in my git tree
> > > graftid=`git-show-ref -s svn`
> > > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > 
> .git/info/grafts
> > > #da783... is the initial commit in my git tree.
> > > git filter-branch $graftid..HEAD
> > > git-svn dcommit
> > > 
> > > Now I get alot of complaints, but it commits to svn.
> > > It takes forever though:
> > > r3 = 55a489bd4f66dd1f641a4676359d7b8911dc7d83 (git-svn)
> > > W: HEAD and refs/remotes/git-svn differ, using rebase:
> > > :100644 100644 f85ae11af7715a224015582724cb2bab87ec914a
> 
> I haven't used filter-branch myself, but you probably need to 
> remove all
> .rev_db* files in $GIT_DIR after running it (git-svn can recreate them
> unless you use the svmRevProps or noMetadata options.

havn't used it either, but I wanted to see if it makes a difference.
I will remember to remove the .rev_db* files next time I try.

filter branch is overkill if the grafts file works as git-svn will rewrite
the commits so once the first dcommit has been made, I can remove the
grafts file.

I do have another project though were I want to fix som odd parenting caused
by set-tree, there I will have to used filter-branch to make it permanet.

> 
> > [SNIP]
> > 
> > Just wanted to add that 1.5.2.2 works with grafts and 
> > that I suspect sub read_commit_parents in git-svn, but as I don't
> > do perl I am stuck.
> 
> Crap, it looks like I completely forgot about the existence
> of grafts while doing this function.

:)
Do you have to worry about grafts in git-svn? 
Can't git plumbing do this for you?

> 
> >      Jocke
> > Oh, Eric W. CC:ed as well this time
> 
> Thanks.
> 
> -- 
> Eric Wong
> 
> 

RE: git-svn 1.5.3 does not understand grafts?

[Joakim Tjernlund]

 

> -----Original Message-----
> From: Eric Wong [mailto:normalperson@yhbt.net] 
> Sent: den 8 september 2007 07:02
> To: Joakim Tjernlund
> Cc: git
> Subject: Re: git-svn 1.5.3 does not understand grafts?
> 
> Joakim Tjernlund <joakim.tjernlund@transmode.se> wrote:
> > On Fri, 2007-09-07 at 18:52 +0200, Joakim Tjernlund wrote:
> > > On Fri, 2007-09-07 at 18:41 +0200, Joakim Tjernlund wrote:
> > > > svnadmin create /usr/local/src/TM/svn-tst/7720-svn/
> > > > svn mkdir  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk -m "Add trunk dir"
> > > > svn mkdir  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp -m "Add swp dir"
> > > > 
> > > > In my git repo I do
> > > > git-svn init  
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > > > git-svn fetch
> > > > git branch svn remotes/git-svn
> > > > #make remotes/git-svn parent to the initial commit in 
> my git tree
> > > > graftid=`git-show-ref -s svn`
> > > > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid 
> > .git/info/grafts
> > > > #da783... is the initial commit in my git tree.
> > > > git-svn dcommit
> > > > 
> > > > fails with:
> > > > Committing to 
> file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp ...
> > > > Commit da783cce390ce013b19f1d308ea6813269c6a6b5
> > > > has no parent commit, and therefore nothing to diff against.
> > > > You should be working from a repository originally 
> created by git-svn
> > > 
> > > Using filter-branch helps, but git-svn isn't too happy:
> > > 
> > > git-svn init  file:///usr/local/src/TM/svn-tst/7720-svn/trunk/swp 
> > > git-svn fetch
> > > git branch svn remotes/git-svn
> > > #make remotes/git-svn parent to the initial commit in my git tree
> > > graftid=`git-show-ref -s svn`
> > > echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > 
> .git/info/grafts
> > > #da783... is the initial commit in my git tree.
> > > git filter-branch $graftid..HEAD
> > > git-svn dcommit
> > > 
> > > Now I get alot of complaints, but it commits to svn.
> > > It takes forever though:
> > > r3 = 55a489bd4f66dd1f641a4676359d7b8911dc7d83 (git-svn)
> > > W: HEAD and refs/remotes/git-svn differ, using rebase:
> > > :100644 100644 f85ae11af7715a224015582724cb2bab87ec914a
> 
> I haven't used filter-branch myself, but you probably need to 
> remove all
> .rev_db* files in $GIT_DIR after running it (git-svn can recreate them
> unless you use the svmRevProps or noMetadata options.
> 
> > [SNIP]
> > 
> > Just wanted to add that 1.5.2.2 works with grafts and 
> > that I suspect sub read_commit_parents in git-svn, but as I don't
> > do perl I am stuck.
> 
> Crap, it looks like I completely forgot about the existence
> of grafts while doing this function.

hmm, I think git-cat-file is to blame.
git-cat-file commit da783cce390ce013b19f1d308ea6813269c6a6b5 does
not list list any parent even though I did
graftid=`git-show-ref -s remotes/git-svn`
echo da783cce390ce013b19f1d308ea6813269c6a6b5 $graftid > .git/info/grafts

 Jocke

Re: git-svn 1.5.3 does not understand grafts?

[Junio C Hamano]

"Joakim Tjernlund" <joakim.tjernlund@transmode.se> writes:

> hmm, I think git-cat-file is to blame.
> git-cat-file commit da783cce390ce013b19f1d308ea6813269c6a6b5 does
> not list list any parent...

The plumbing cat-file does not deal with grafts and this is
deliberate.  Otherwise you would not be able to find the true
set of parents when you'd want to.

So do not blame cat-file, but blame the Porcelain that uses
cat-file to read a commit object, without annotating what it
read with what is in grafts, in this case your command line
experiment ;-).

The log family of commands and rev-list plumbing while
traversing commit ancestry chain do take grafts into account.

One caveat is pretty=raw output format shows true parents
without grafts on "parent " header line, while the "commit "
fake header prepended in the output for each commit shows the
parents that takes into account.

To illustrate, if you forge the history and say the parent of
1ddea77 is 5da1606 (when the true parent is 820eca68) with
grafts mechanism, here is what happens:

    $ echo '1ddea77e449ef28d8a7c74521af21121ab01abc0 5da1606d0bf5b970fadfa0ca91618a1e871f6755' >.git/info/grafts
    $ git show -s --pretty=raw --parents 1ddea77
    commit 1ddea77e449ef28d8a7c74521af21121ab01abc0 5da1606d0bf5b970fadfa0ca91618a1e871f6755
    tree e9e61bc801438062978ff47b0963c536ed1e51a9
    parent 820eca68c2577d7499d203d7f4f7ae479b577683
    author Nick Hengeveld <nickh@reactrix.com> 1127757131 -0700
    committer Junio C Hamano <junkio@cox.net> 1127805558 -0700

        [PATCH] Return CURL error message when object transfer fails

        Return CURL error message when object transfer fails
        ...
    $ git-cat-file commit 1ddea77
    tree e9e61bc801438062978ff47b0963c536ed1e51a9
    parent 820eca68c2577d7499d203d7f4f7ae479b577683
    author Nick Hengeveld <nickh@reactrix.com> 1127757131 -0700
    committer Junio C Hamano <junkio@cox.net> 1127805558 -0700

    [PATCH] Return CURL error message when object transfer fails

    Return CURL error message when object transfer fails
    ...

[PATCH] git-svn: understand grafts when doing dcommit

[Eric Wong]

Use the rev-list --parents functionality to read the parents
of the commit.  cat-file only shows the raw object with the
original parents and doesn't take into account grafts; so
we'll rely on rev-list machinery for the smarts here.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
---
  Junio C Hamano <gitster@pobox.com> wrote:
  > "Joakim Tjernlund" <joakim.tjernlund@transmode.se> writes:
  > 
  > > hmm, I think git-cat-file is to blame.
  > > git-cat-file commit da783cce390ce013b19f1d308ea6813269c6a6b5 does
  > > not list list any parent...
  > 
  > The plumbing cat-file does not deal with grafts and this is
  > deliberate.  Otherwise you would not be able to find the true
  > set of parents when you'd want to.
  > 
  > So do not blame cat-file, but blame the Porcelain that uses
  > cat-file to read a commit object, without annotating what it
  > read with what is in grafts, in this case your command line
  > experiment ;-).
  > 
  > The log family of commands and rev-list plumbing while
  > traversing commit ancestry chain do take grafts into account.
  > 
  > One caveat is pretty=raw output format shows true parents
  > without grafts on "parent " header line, while the "commit "
  > fake header prepended in the output for each commit shows the
  > parents that takes into account.
  > 
  > To illustrate, if you forge the history and say the parent of
  > 1ddea77 is 5da1606 (when the true parent is 820eca68) with
  > grafts mechanism, here is what happens:
  > 
  >     $ echo '1ddea77e449ef28d8a7c74521af21121ab01abc0 5da1606d0bf5b970fadfa0ca91618a1e871f6755' >.git/info/grafts
  >     $ git show -s --pretty=raw --parents 1ddea77
  >     commit 1ddea77e449ef28d8a7c74521af21121ab01abc0 5da1606d0bf5b970fadfa0ca91618a1e871f6755
  >     tree e9e61bc801438062978ff47b0963c536ed1e51a9
  >     parent 820eca68c2577d7499d203d7f4f7ae479b577683
  >     author Nick Hengeveld <nickh@reactrix.com> 1127757131 -0700
  >     committer Junio C Hamano <junkio@cox.net> 1127805558 -0700
  > 
  >         [PATCH] Return CURL error message when object transfer fails
  > 
  >         Return CURL error message when object transfer fails
  >         ...

  Interesting.  I didn't know about the --parents option before.

 git-svn.perl |   11 +++--------
 1 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/git-svn.perl b/git-svn.perl
index fbd4691..f818160 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -841,14 +841,9 @@ sub working_head_info {
 
 sub read_commit_parents {
 	my ($parents, $c) = @_;
-	my ($fh, $ctx) = command_output_pipe(qw/cat-file commit/, $c);
-	while (<$fh>) {
-		chomp;
-		last if '';
-		/^parent ($sha1)/ or next;
-		push @{$parents->{$c}}, $1;
-	}
-	close $fh; # break the pipe
+	chomp(my $p = command_oneline(qw/rev-list --parents -1/, $c));
+	$p =~ s/^($c)\s*// or die "rev-list --parents -1 $c failed!\n";
+	@{$parents->{$c}} = split(/ /, $p);
 }
 
 sub linearize_history {
-- 
Eric Wong