Document clone of clone loosing branches?

Document clone of clone loosing branches?

[Vaclav Hanzl]

I wander whether man git-clone is correct when it says "creates
remote-tracking branches for each branch in the cloned repository".

IMHO remote-tracking branches in the original repository _are_
branches and they are _not_ cloned (when using git-clone with no
options) - maybe this is worth noting very explicitly?

When git newby like me converts a CVS repository, containing just few
short old branches (stable release bug fixes) and then clones it
around, with naive belief that clone is a 1:1 copy or something close,
nasty surprise can happen:

 - converted repository has those branches, OK
 - clone of it also has them, but as a remote tracking branches
 - clone of clone has it as dangling objects only (can go away later)

Trying to play it safe, I used git-clone many times while starting
with git, and I got really nervous when I first discovered that my old
stable release bug fix branch is not visible in some repositories :-)

Is it just my failure to read those few hundred man pages carefully
enough (I did my best :-) ), or something worth fixing in man
git-clone and tutorials?

Regards,

Vaclav Hanzl

Re: Document clone of clone loosing branches?

[Jeff King]

On Sat, Jun 14, 2008 at 03:05:48PM +0200, Vaclav Hanzl wrote:

> I wander whether man git-clone is correct when it says "creates
> remote-tracking branches for each branch in the cloned repository".
> 
> IMHO remote-tracking branches in the original repository _are_
> branches and they are _not_ cloned (when using git-clone with no
> options) - maybe this is worth noting very explicitly?

The new repository has remote tracking branches of the _regular_
branches that are in the original repository. So the statement is
correct; git-clone creates remote-tracking branches, and it makes one
such branch for each branch in the cloned repository.

Unless you are complaining that it makes one for each non-remote branch
in the cloned repository. But I think it is the general pattern to refer
to things in refs/heads/ as simply unadorned "branch". If you want to
say "all refs, including remote-tracking branches", you would typically
say "refs" (which would also include tags).

> When git newby like me converts a CVS repository, containing just few
> short old branches (stable release bug fixes) and then clones it
> around, with naive belief that clone is a 1:1 copy or something close,
> nasty surprise can happen:

In that sense, clone is a bit of a misnomer, because the two _are_
different. The cloned repo has its origin pointing to the original repo,
and the origin of the original repo (and its associated tracking
branches) are forgotten.

>  - converted repository has those branches, OK
>  - clone of it also has them, but as a remote tracking branches
>  - clone of clone has it as dangling objects only (can go away later)

The clone of clone does not have dangling objects; either it sees a ref
(because it is a branch in the clone) and it grabs the objects, or it
does not see it, in which case it does not download those objects.

> Trying to play it safe, I used git-clone many times while starting
> with git, and I got really nervous when I first discovered that my old
> stable release bug fix branch is not visible in some repositories :-)

Yes, this is sometimes annoying if what you _really_ want is another
clone of the clone's origin. For me, this happens because I want to
clone Junio's git.git (to do some experimentation that might trash the
repo), but:

  - I am too lazy to type Junio's git URL
  - I want the hard-link space-saving of cloning my local repo

So I do something like:

  ref=/path/to/my/git/repo
  git clone --reference $ref `cd $ref && git config remote.origin.url`

which you can easily put in an alias.

-Peff

Re: Document clone of clone loosing branches?

[Jakub Narebski]

Vaclav Hanzl <hanzl@noel.feld.cvut.cz> writes:

> I wander whether man git-clone is correct when it says "creates
> remote-tracking branches for each branch in the cloned repository".
> 
> IMHO remote-tracking branches in the original repository _are_
> branches and they are _not_ cloned (when using git-clone with no
> options) - maybe this is worth noting very explicitly?
[...]

The idea is for git-clone to clone (by default) _your_ work, not sb
else work.  Think about two repositories, fetching from each other:
you don't want for branches to proliferate like mad, remote of remote,
then remote of remote of remote, and ad infinitum.

Besides there is I think implicit assumption that public repositories
one might want to clone are _bare_ repositories, 1:1 or mirror
refspecs, which simply do not contain remote tracking branches.

-- 
Jakub Narebski
Poland
ShadeHawk on #git

Re: Document clone of clone loosing branches?

[Lea Wiemann]

Vaclav Hanzl wrote:
> with naive belief that clone is a 1:1 copy or something close,
> nasty surprise can happen:

I got bitten by that, too.  Perhaps the intro paragraph of git-clone.txt 
(man git-clone) could mention that remote branches are not cloned or so. 
  (I don't know git-clone well enough to be able to phrase it 
accurately, but perhaps someone else wants to send a documentation patch...)

-- Lea

Re: Document clone of clone ... bug??

[Vaclav Hanzl]

> The clone of clone does not have dangling objects; either it sees a ref
> (because it is a branch in the clone) and it grabs the objects, or it
> does not see it, in which case it does not download those objects.

Yes, there should not be a dangling object, but I actually got one. I
was surprised, but I thought it is just an undocumented benign behavior
(optimization overkill - clone rather gets those objects instead of
thinking what it needs). Now I think it may be a bug.

Can someone with deeper knowledge and fresh git please try this:

 rm -rf A B C
 mkdir A B C
 (cd A; mkdir X; cd X; git init; echo x>x; git add x; git commit -m xxx;
  git checkout -b br; echo y>y; git add y; git commit -m yyy;
  git checkout master)
 (cd B; git clone ../A/X)
 (cd C; git clone ../B/X; cd X; git fsck --full)

With my 11 days old version of git, I get:

 dangling commit ...

and 'git show ...' reveals that this commit it that otherwise
(rightfully) lost branch 'br'.

SHA1 is changing when I repeat this (due to dates in reflogs??).

When I omit 'git checkout master', no dangling commit appears. Strange.

Is it my faulty thinking, benign undocumented thing, or a bug?

Vaclav Hanzl

Re: Document clone of clone ... bug??

[Jakub Narebski]

Vaclav Hanzl <hanzl@noel.feld.cvut.cz> writes:

> > The clone of clone does not have dangling objects; either it sees a ref
> > (because it is a branch in the clone) and it grabs the objects, or it
> > does not see it, in which case it does not download those objects.
> 
> Yes, there should not be a dangling object, but I actually got one. I
> was surprised, but I thought it is just an undocumented benign behavior
> (optimization overkill - clone rather gets those objects instead of
> thinking what it needs).
[...]
>  (cd B; git clone ../A/X)

_Local_ clone?  This is result of optimization; in cloning over local
filesystem case git-clone simply hardlinks object database (if
possible) instead of transferring objects.  This was only on request
in earlier versions of git.

You can use filr:// protocol to force generating of pack-file and
actual transfer of objects.
-- 
Jakub Narebski
Poland
ShadeHawk on #git

Re: Document clone of clone ... bug??

[Vaclav Hanzl]

> _Local_ clone?  This is result of optimization; in cloning over local
> filesystem case git-clone simply hardlinks object database (if
> possible) instead of transferring objects.  This was only on request
> in earlier versions of git.
>
> You can use filr:// protocol to force generating of pack-file and
> actual transfer of objects.


Still dangling even with 'file:', using (in my case) this:

 pwd
 rm -rf A B C
 mkdir A B C
 (cd A; mkdir X; cd X; git init; echo x>x; git add x; git commit -m xxx;
  git checkout -b y; echo y>y; git add y; git commit -m yyy;
  git checkout master)
 (cd B; git clone file:///home/kroupa/tmp/gittest/A/X; cd X; git branch -a)
 (cd C; git clone file:///home/kroupa/tmp/gittest/B/X; cd X; git branch -a; git fsck --full)


The actual result of pasting this to shell is:

~/tmp/gittest>pwd
/home/kroupa/tmp/gittest
~/tmp/gittest>rm -rf A B C
~/tmp/gittest>mkdir A B C
~/tmp/gittest>(cd A; mkdir X; cd X; git init; echo x>x; git add x; git commit -m xxx;
>  git checkout -b y; echo y>y; git add y; git commit -m yyy;
>  git checkout master)
Initialized empty Git repository in .git/
Created initial commit ec59a7e: xxx
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 x
Switched to a new branch "y"
Created commit 2be193d: yyy
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 y
Switched to branch "master"
~/tmp/gittest>(cd B; git clone file:///home/kroupa/tmp/gittest/A/X; cd X; git branch -a)
Initialized empty Git repository in /home/kroupa/tmp/gittest/B/X/.git/
remote: Counting objects: 6, done.
remote: Compressing objects: 100% (3/3), done.
remote: Total 6 (delta 0), reused 0 (delta 0)
Receiving objects: 100% (6/6), done.
* master
  origin/HEAD
  origin/master
  origin/y
~/tmp/gittest>(cd C; git clone file:///home/kroupa/tmp/gittest/B/X; cd X; git branch -a; git fsck --full)
Initialized empty Git repository in /home/kroupa/tmp/gittest/C/X/.git/
remote: Counting objects: 6, done.
remote: Compressing objects: 100% (3/3), done.
remote: Total 6 (delta 0), reused 6 (delta 0)
Receiving objects: 100% (6/6), done.
* master
  origin/HEAD
  origin/master
dangling commit 2be193dc7dc3e1051dcf5af9d03f7587b61f9fc3


And the dangling object is:


~/tmp/gittest>cd C/X; git show 2be193d
commit 2be193dc7dc3e1051dcf5af9d03f7587b61f9fc3
Author: kroupa <kroupa@noli.localdomain>
Date:   Sat Jun 14 22:47:46 2008 +0200

    yyy

diff --git a/y b/y
new file mode 100644
index 0000000..975fbec
--- /dev/null
+++ b/y
@@ -0,0 +1 @@
+y



Any thoughts?

Vaclav

Re: Document clone of clone loosing branches?

[Vaclav Hanzl]

Lea Wiemann wrote:
> I got bitten by that, too.  Perhaps the intro paragraph of git-clone.txt 
> (man git-clone) could mention that remote branches are not cloned or so. 
>   (I don't know git-clone well enough to be able to phrase it 
> accurately, but perhaps someone else wants to send a documentation patch...)

This is exactly what I would like to happen. (If nobody seems
interested, I might propose my own bad very first patch few days or
weeks later...)

Jeff King wrote:
> The new repository has remote tracking branches of the _regular_
> branches that are in the original repository. So the statement is
> correct; git-clone creates remote-tracking branches, and it makes one
> such branch for each branch in the cloned repository.
> 
> Unless you are complaining that it makes one for each non-remote branch
> in the cloned repository. But I think it is the general pattern to refer
> to things in refs/heads/ as simply unadorned "branch". If you want to
> say "all refs, including remote-tracking branches", you would typically
> say "refs" (which would also include tags).

I am not sure that the term 'branch' can be reasonably expected to
mean 'regular branch' unless specified otherwise. For example, 'man
git' says:

       git-branch(1)
          List, create, or delete branches.

It can also list remote-tracking branches, cannot it? Or:

       git-show-branch(1)
          Show branches and their commits.

Can also show remote-tracking branches, cannot it?

Even if 'branch' were very well known to mean 'regular branch', I
would still argue that 'man clone' is a very good place to define
these vocabulary conventions.

So I still think that 'man clone' is wrong as it stands now. It is not
true that all 'branches' are cloned. It would be better to say quite
explicitly that regular branches are cloned and remote tracking
branches are not.


Jakub Narebski wrote:
> The idea is for git-clone to clone (by default) _your_ work, not sb
> else work.  Think about two repositories, fetching from each other:
> you don't want for branches to proliferate like mad, remote of remote,
> then remote of remote of remote, and ad infinitum.
> 
> Besides there is I think implicit assumption that public repositories
> one might want to clone are _bare_ repositories, 1:1 or mirror
> refspecs, which simply do not contain remote tracking branches.


Yes. It would be no shame if an explanation like this made it to 'man
clone'?

After all, how many other commands do distinguish regular branches and
remote tracking branches? Even if there are any other (I do not know),
git-clone is likely the most prominent of them and 'man git-clone' is
quite good place to document this. Unless it is explained in 'man git'
itself (I think it is not now).

(Thought I am quite happy with UNIX tradition of very exact and very
condensed man pages, up to the point of being a hard puzzle, and I
agree that man pages are no tutorial, in this case I would be happy to
see 'regular branches' and 'remote tracking branches' clearly
distinguished in 'man git-clone' itself, without an implicit reference
to 'usual' meaning of words among geeks.)

Regards,

Vaclav Hanzl

P.S. Sorry for screwing up mail threads by this synthetic answer but I
thought it is not worth 3 messages (?)

Re: Document clone of clone loosing branches?

[Junio C Hamano]

Vaclav Hanzl <hanzl@noel.feld.cvut.cz> writes:

> I am not sure that the term 'branch' can be reasonably expected to
> mean 'regular branch' unless specified otherwise. For example, 'man
> git' says:
>
>        git-branch(1)
>           List, create, or delete branches.
>
> It can also list remote-tracking branches, cannot it? Or:
>
>        git-show-branch(1)
>           Show branches and their commits.
>
> Can also show remote-tracking branches, cannot it?

These fall into "quibbling" category, but that judgement can only be made
by people who know the history.

Updates to glossary and other introductory documents might be necessary.
For example, the entry about "tracking branch" in the glossary still talks
about the ancient convention of copying 'master' to 'origin' as a regular
branch:

    [[def_tracking_branch]]tracking branch::
            A regular git <<def_branch,branch>> that is used to follow changes from
            another <<def_repository,repository>>. A tracking
            branch should not contain direct modifications or have local commits
            made to it. A tracking branch can usually be
            identified as the right-hand-side <<def_ref,ref>> in a Pull:
            <<def_refspec,refspec>>.

This does _not_ reflect post v1.3.0 reality at all.  No git more recent
than Apr 2006 has used a "regular git branch" for tracking.

It probably is enough to say:

        A ref that is used to follow changes from another repository.
	In modern git, they are found in `refs/remotes/` hierarchy.

because you cannot add "direct modifications or have local commits" to
them anymore.

Re: Document clone of clone loosing branches?

[Jakub Narebski]

Vaclav Hanzl wrote:
> Jakub Narebski wrote:
>>
>> The idea is for git-clone to clone (by default) _your_ work, not sb
>> else work.  Think about two repositories, fetching from each other:
>> you don't want for branches to proliferate like mad, remote of remote,
>> then remote of remote of remote, and ad infinitum.
>> 
>> Besides there is I think implicit assumption that public repositories
>> one might want to clone are _bare_ repositories, 1:1 or mirror
>> refspecs, which simply do not contain remote tracking branches. 
> 
> Yes. It would be no shame if an explanation like this made it to 'man
> clone'?

The question of course is _what_ to put into git-clone(1), what to
generic documentation in git(1), and what in "Git User's Manual".

> After all, how many other commands do distinguish regular branches and
> remote tracking branches?

Errr... many of them? git-branch treats regular branches (refs/heads/*)
and remote-tracking branches (refs/remotes/<remotename>/*) differently
(compare "git branch" and "git branch -r", and "git branch -a").
git-checkout treats regular branches (can checkout) different from
other refs, including remote-tracking branches (result in detached
HEAD).

> Even if there are any other (I do not know), 
> git-clone is likely the most prominent of them and 'man git-clone' is
> quite good place to document this. Unless it is explained in 'man git'
> itself (I think it is not now).

I'm not sure how it is put in documentation, but I wouldn't wonder
if it is not dicumented, because most of gitters who can write this
documentation do know the difference between regular branches and
remote-tracking branches, and know recoomended workflows and best
practices.
 
> (Thought I am quite happy with UNIX tradition of very exact and very
> condensed man pages, up to the point of being a hard puzzle, and I
> agree that man pages are no tutorial, in this case I would be happy to
> see 'regular branches' and 'remote tracking branches' clearly
> distinguished in 'man git-clone' itself, without an implicit reference
> to 'usual' meaning of words among geeks.)

So, what should be mentioned ar two facts, I think.  (a) that git-clone
copies only regular branches and tags; it does not copy remote-tracking
branches, it does not copy stash, it does not copy reflogs, it does not
copy StGIT stacks...  (b) that recommended workflow (best practice) is
to have public published repository which is bare clone
(1:1 correspondnce) of interesting subset of refs.

-- 
Jakub Narebski
Poland

Re: Document clone of clone loosing branches?

[Vaclav Hanzl]

> These fall into "quibbling" category, but that judgement can only be made
> by people who know the history.

I allowed myself to quibble much more than usually as I think it
serves a good technical purpose. I am a new git user but quite
pervasive in getting all the info I can (I have bound copy of all git
man pages and about ten tutorials, diligently devoting much of my time
last month to reading it all; generally I am not scared by strange
things like plain Tex, FORTH, Prolog etc.) so I might serve as a good
example of user who tried hard and still did not get it with current
docs.

But it is a thin border, so please do not hesitate to shut me up if my
judgement of technical merit is wrong.

> Updates to glossary and other introductory documents might be necessary.
> For example, the entry about "tracking branch" in the glossary still talks
> about the ancient convention of copying 'master' to 'origin' as a regular
> branch:

I would appreciate this update ;-)

Regards (and big thanks for git!),

Vaclav

Re: Document clone of clone loosing branches?

[Jakub Narebski]

Vaclav Hanzl <hanzl@noel.feld.cvut.cz> writes:

> I wander whether man git-clone is correct when it says "creates
> remote-tracking branches for each branch in the cloned repository".
> 
> IMHO remote-tracking branches in the original repository _are_
> branches and they are _not_ cloned (when using git-clone with no
> options) - maybe this is worth noting very explicitly?

It probably should read "for each _regular_ branch in the cloned
repository".

And of course if you are creating bare clone it does mirror regular
branches (1:1 mapping) instead of remote-tracking branches (mappping
from refs/heads/* into refs/remotes/origin/* namespace).

[...]
> Is it just my failure to read those few hundred man pages carefully
> enough (I did my best :-) ), or something worth fixing in man
> git-clone and tutorials?

Even if it is just your failure it would be worh correcting
(enhancing) documentation to make it more clear.

-- 
Jakub Narebski
Poland
ShadeHawk on #git

[PATCH] Documentation: Note about the meaning of "clone"

[Robin Rosenberg]

Clarify that a clone is not an exact copy.

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
---
 Documentation/git-clone.txt |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
index 7973e6a..c9bc627 100644
--- a/Documentation/git-clone.txt
+++ b/Documentation/git-clone.txt
@@ -31,7 +31,12 @@ This default configuration is achieved by creating references to
 the remote branch heads under `$GIT_DIR/refs/remotes/origin` and
 by initializing `remote.origin.url` and `remote.origin.fetch`
 configuration variables.
-
++
+*NOTE*: Although this command is called clone, the clone is not identical
+in all respects. Local branches in the repository being cloned
+becomes remote tracking branches in the clone and remote tracking
+branches are not cloned at all. For security reasone the config sections
+and triggers are not cloned either.
 
 OPTIONS
 -------
-- 
1.5.5.1.178.g1f811

PATCH] cvsimport: Clarification on the use of -r

[Robin Rosenberg]

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
---
 Documentation/git-cvsimport.txt |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-cvsimport.txt b/Documentation/git-cvsimport.txt
index 2f9b35f..b873882 100644
--- a/Documentation/git-cvsimport.txt
+++ b/Documentation/git-cvsimport.txt
@@ -28,8 +28,12 @@ You should *never* do any work of your own on the branches that are
 created by git-cvsimport.  By default initial import will create and populate a
 "master" branch from the CVS repository's main branch which you're free
 to work with; after that, you need to 'git merge' incremental imports, or
-any CVS branches, yourself.  It is advisable to specify a named remote via
--r to separate and protect the incoming branches.
+any CVS branches, yourself.
+
+It is advisable to specify a named remote via -r to separate and protect
+the incoming branches if you intend to do your work in the same repository. If
+you want to have a cvs import-only repostory which you clone to your work
+repository, then do not use the -r option.
 
 
 OPTIONS
@@ -56,7 +60,7 @@ OPTIONS
 -r <remote>::
 	The git remote to import this CVS repository into.
 	Moves all CVS branches into remotes/<remote>/<branch>
-	akin to the git-clone --use-separate-remote option.
+	akin what git clone does when cloning a repository.
 
 -o <branch-for-HEAD>::
 	When no remote is specified (via -r) the 'HEAD' branch
-- 
1.5.5.1.178.g1f811

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Jakub Narebski]

Robin Rosenberg wrote:
>
> Clarify that a clone is not an exact copy.

> +*NOTE*: Although this command is called clone, the clone is not identical
> +in all respects. Local branches in the repository being cloned
> +becomes remote tracking branches in the clone and remote tracking
> +branches are not cloned at all. For security reasone the config sections
> +and triggers are not cloned either.

One nitpick, one comment, one historical comment.

Nitpick: Actually biological clone is usually not identical in
phenotype, and we know now that due to different gene expression
it can have different genotype as well. ;-)

COMMENT: when you do "git clone --bare" it mirrors local (regular)
branches in 1:1 correspondence; but it still doesn't clone anything
outside refs/heads/ and refs/remotes (and HEAD).

Historical comment: git-clone used to do 1:1 mapping even for non-bare
clone, with exception of <current branch> -> origin mapping, before
behavior provided by --use-separate-remotes was made default (thanks
Carl!).

-- 
Jakub Narebski
Poland

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Wincent Colaiuta]

El 15/6/2008, a las 15:05, Robin Rosenberg escribió:

> Clarify that a clone is not an exact copy.
>
> Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
> ---
> Documentation/git-clone.txt |    7 ++++++-
> 1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
> index 7973e6a..c9bc627 100644
> --- a/Documentation/git-clone.txt
> +++ b/Documentation/git-clone.txt
> @@ -31,7 +31,12 @@ This default configuration is achieved by  
> creating references to
> the remote branch heads under `$GIT_DIR/refs/remotes/origin` and
> by initializing `remote.origin.url` and `remote.origin.fetch`
> configuration variables.
> -
> ++
> +*NOTE*: Although this command is called clone, the clone is not  
> identical
> +in all respects. Local branches in the repository being cloned
> +becomes remote tracking branches in the clone and remote tracking

Grammar: "become", not "becomes"

>
> +branches are not cloned at all. For security reasone the config  
> sections
> +and triggers are not cloned either.

Typo: "security reasons", not "security reasone"

You might also want to mention that the clone is not necessarily a  
redundant _copy_ of the original repo, because at least for local  
clones on the same file system clone will use hard links rather than  
actually making a copy, unless you explicitly tell it not to.

W

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Vaclav Hanzl]

> You might also want to mention that the clone is not necessarily a  
> redundant _copy_ of the original repo, because at least for local  
> clones on the same file system clone will use hard links rather than  
> actually making a copy, unless you explicitly tell it not to.

At the moment this is covered in description of the --local option
(I personally found it very easy to get this knowledge, dislike other
differences from 1:1)

Vaclav

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Vaclav Hanzl]

> +*NOTE*: Although this command is called clone, the clone is not identical
> +in all respects. Local branches in the repository being cloned
> +becomes remote tracking branches in the clone and remote tracking
> +branches are not cloned at all. For security reasone the config sections
> +and triggers are not cloned either.

In order to better specify what gets cloned and what does not, one
might also replace "active branch" (under DESCRIPTION) with "current
branch".

According to grep in Documentation/*.txt, "current branch" is used
much more often than "active branch". Most frequent use of term
"active branch" is found in git-fast-import.txt and it seems to mean
something else there.

(The fact that tiny volatile detail - which branch happens to be
checked out at the moment of clone - has profound influence on the
result of clone was quite a surprise for me, so I would like to
see this described as exactly as possible.)

Regards

Vaclav

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Miklos Vajna]

[-- Attachment #1: Type: text/plain, Size: 447 bytes --]

On Sun, Jun 15, 2008 at 03:05:27PM +0200, Robin Rosenberg <robin.rosenberg.lists@dewire.com> wrote:
> +*NOTE*: Although this command is called clone, the clone is not identical
> +in all respects. Local branches in the repository being cloned
> +becomes remote tracking branches in the clone and remote tracking
> +branches are not cloned at all. For security reasone the config sections
> +and triggers are not cloned either.

s/triggers/hooks/?

[-- Attachment #2: Type: application/pgp-signature, Size: 197 bytes --]

Re: [PATCH] Documentation: Note about the meaning of "clone"

[Junio C Hamano]

Robin Rosenberg <robin.rosenberg.lists@dewire.com> writes:

> Clarify that a clone is not an exact copy.
>
> Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
> ---
>  Documentation/git-clone.txt |    7 ++++++-
>  1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
> index 7973e6a..c9bc627 100644
> --- a/Documentation/git-clone.txt
> +++ b/Documentation/git-clone.txt
> @@ -31,7 +31,12 @@ This default configuration is achieved by creating references to
>  the remote branch heads under `$GIT_DIR/refs/remotes/origin` and
>  by initializing `remote.origin.url` and `remote.origin.fetch`
>  configuration variables.
> -
> ++
> +*NOTE*: Although this command is called clone, the clone is not identical
> +in all respects. Local branches in the repository being cloned
> +becomes remote tracking branches in the clone and remote tracking
> +branches are not cloned at all. For security reasone the config sections
> +and triggers are not cloned either.

Thanks.

But the above will not lose any information content if "Although... clone,"
is dropped.  It in fact, dropping that would make it even clearer.  

Saying only "beware that neither X nor Y nor Z is done" leaves readers
wondering "why not".  Saying "you may assume W but that is not the case"
is the same.  How about expressing it a bit differently and in a more
positive way?  Documentation is not a place to express your frustration
you felt immediately after you found out that your initial assumption did
not match reality.

And there is no triggers in git.  If you are improving documentation,
please get your terminology straight.

I think the first three paragraphs of this manual page need major
overhaul.  There were not much difference between bare and non-bare clone
when historical layout was used, but exactly because a clone with a
working tree always use separate remotes layout, what they do is vastly
different these days.

Points to stress, and the order to present them, in the rewritten first
paragraphs would be:

 - There are two different kind of clones.  A bare one and non bare one.

 - A non-bare one is a way to prepare where you work in.  It is assumed
   that you will want to keep updating the resulting repository from the
   source of the cloning operation from time to time, so 'origin' is set
   up for you automatically to track its branches in remotes/origin.

 - A bare one is a way to prepare where you push into so that others can
   fetch from it.  IOW, it is a place people meet to exchange history, not
   a place where somebody actually works in to build history.  It is
   expected that people will push into the resulting repository from
   elsewhere to update it, rather than somebody will fetch into it further
   from any 'origin'.  No 'origin' is made, and branches are copied 1:1.

 - In either case, only the information from the originating repository
   that are designed to be shared are propagated.  That includes branches
   and tags, but not things that are specific for working in the
   originating repository such as config, stash, hooks and remote tracking
   branches.