# [PATCH] git-checkout(1) mention fate of extraneous files

13 messages from 2009-01-17 to 2009-01-20. Participants: jidanni@jidanni.org, Markus Heidelberg, Boyd Stephen Smith Jr., Johannes Schindelin, Junio C Hamano.
Thread: https://gitlist.dev/t/17216

## jidanni@jidanni.org, 2009-01-17 00:36

Subject: [PATCH] git-checkout(1) mention fate of extraneous files
Message-ID: <87k58u4vlq.fsf@jidanni.org>
URL: https://gitlist.dev/e/87k58u4vlq.fsf%40jidanni.org

```
Signed-off-by: jidanni <jidanni@jidanni.org>
---
 Documentation/git-checkout.txt |   13 +++++++------
 1 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 9cd5151..bce31c7 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -14,12 +14,13 @@ SYNOPSIS
 DESCRIPTION
 -----------
 
-When <paths> are not given, this command switches branches by
-updating the index and working tree to reflect the specified
-branch, <branch>, and updating HEAD to be <branch> or, if
-specified, <new_branch>.  Using -b will cause <new_branch> to
-be created; in this case you can use the --track or --no-track
-options, which will be passed to `git branch`.
+When <paths> are not given, this command switches branches by updating
+the index and working tree to reflect the specified branch, <branch>,
+and updating HEAD to be <branch> or, if specified, <new_branch>. (No
+extraneous files present are deleted, use linkgit:git-clean[1] for a
+pristine checkout.) Using -b will cause <new_branch> to be created; in
+this case you can use the --track or --no-track options, which will be
+passed to `git branch`.
 
 As a convenience, --track will default to create a branch whose
 name is constructed from the specified branch name by stripping
-- 
1.6.0.6

```

## Markus Heidelberg, 2009-01-17 12:57

Subject: Re: [PATCH] git-checkout(1) mention fate of extraneous files
Message-ID: <200901171357.18005.markus.heidelberg@web.de>
URL: https://gitlist.dev/e/200901171357.18005.markus.heidelberg%40web.de
In-Reply-To: <87k58u4vlq.fsf@jidanni.org>

```
jidanni@jidanni.org, 17.01.2009:
> Signed-off-by: jidanni <jidanni@jidanni.org>
> ---
>  Documentation/git-checkout.txt |   13 +++++++------
>  1 files changed, 7 insertions(+), 6 deletions(-)

> -When <paths> are not given, this command switches branches by
> -updating the index and working tree to reflect the specified
> -branch, <branch>, and updating HEAD to be <branch> or, if
> -specified, <new_branch>.  Using -b will cause <new_branch> to
> -be created; in this case you can use the --track or --no-track
> -options, which will be passed to `git branch`.
> +When <paths> are not given, this command switches branches by updating
> +the index and working tree to reflect the specified branch, <branch>,
> +and updating HEAD to be <branch> or, if specified, <new_branch>. (No
> +extraneous files present are deleted, use linkgit:git-clean[1] for a
> +pristine checkout.) Using -b will cause <new_branch> to be created; in
> +this case you can use the --track or --no-track options, which will be
> +passed to `git branch`.

Why do you reformat the whole paragraph? Just inserting your sentence
would give a much nicer diff for easier review, it's no difference for
asciidoc. Indeed to find the change, I just copied the old and new text
into two Vim windows, reformatted and diffed them.

Then you would get this

  Documentation/git-checkout.txt |   2 ++
  1 files changed, 2 insertions(+), 0 deletions(-)

Markus

```

## jidanni@jidanni.org, 2009-01-17 18:35

Subject: Re: [PATCH] git-checkout(1) mention fate of extraneous files
Message-ID: <877i4teq78.fsf@jidanni.org>
URL: https://gitlist.dev/e/877i4teq78.fsf%40jidanni.org
In-Reply-To: <200901171357.18005.markus.heidelberg@web.de>

```
MH> Why do you reformat the whole paragraph?

OK, glad to know that I don't need to!!

```

## jidanni@jidanni.org, 2009-01-19 22:45

Subject: [PATCH,v2] git-checkout(1): mention fate of extraneous files
Message-ID: <87priivrt3.fsf_-_@jidanni.org>
URL: https://gitlist.dev/e/87priivrt3.fsf_-_%40jidanni.org
In-Reply-To: <877i4teq78.fsf@jidanni.org>

```
Signed-off-by: jidanni <jidanni@jidanni.org>
---
 Documentation/git-checkout.txt |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 9cd5151..58abdc6 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -17,7 +17,8 @@ DESCRIPTION
 When <paths> are not given, this command switches branches by
 updating the index and working tree to reflect the specified
 branch, <branch>, and updating HEAD to be <branch> or, if
-specified, <new_branch>.  Using -b will cause <new_branch> to
+specified, <new_branch>. (No files are deleted, use linkgit:git-clean[1]
+for a pristine checkout.) Using -b will cause <new_branch> to
 be created; in this case you can use the --track or --no-track
 options, which will be passed to `git branch`.
 
-- 
1.6.0.6

```

## Boyd Stephen Smith Jr., 2009-01-19 23:16

Subject: Re: [PATCH,v2] git-checkout(1): mention fate of extraneous files
Message-ID: <200901191716.59373.bss@iguanasuicide.net>
URL: https://gitlist.dev/e/200901191716.59373.bss%40iguanasuicide.net
In-Reply-To: <87priivrt3.fsf_-_@jidanni.org>

```
>-specified, <new_branch>.  Using -b will cause <new_branch> to
>+specified, <new_branch>. (No files are deleted, use linkgit:git-clean[1]
>+for a pristine checkout.) Using -b will cause <new_branch> to

The parenthetical remark is not true, here:
$ git status
# On branch anagrams
nothing to commit (working directory clean)
$ ls
anagram  fsdupfind
$ git checkout master
Switched to branch "master"
$ ls
fsdupfind

I think you mean "No untracked content is removed,...".
-- 
Boyd Stephen Smith Jr.                     ,= ,-_-. =. 
bss@iguanasuicide.net                     ((_/)o o(\_))
ICQ: 514984 YM/AIM: DaTwinkDaddy           `-'(. .)`-' 
http://iguanasuicide.net/                      \_/     

```

## jidanni@jidanni.org, 2009-01-19 23:31

Subject: Re: [PATCH,v3] git-checkout(1): mention fate of extraneous files
Message-ID: <87hc3uvpnh.fsf_-_@jidanni.org>
URL: https://gitlist.dev/e/87hc3uvpnh.fsf_-_%40jidanni.org
In-Reply-To: <200901191716.59373.bss@iguanasuicide.net>

```
Signed-off-by: jidanni <jidanni@jidanni.org>
---
Thanks Boyd.
 Documentation/git-checkout.txt |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 9cd5151..56e1ec9 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -17,7 +17,8 @@ DESCRIPTION
 When <paths> are not given, this command switches branches by
 updating the index and working tree to reflect the specified
 branch, <branch>, and updating HEAD to be <branch> or, if
-specified, <new_branch>.  Using -b will cause <new_branch> to
+specified, <new_branch>. (To also delete untracked content
+use linkgit:git-clean[1].) Using -b will cause <new_branch> to
 be created; in this case you can use the --track or --no-track
 options, which will be passed to `git branch`.
 
-- 
1.6.0.6

```

## Johannes Schindelin, 2009-01-19 23:42

Subject: Re: [PATCH,v2] git-checkout(1): mention fate of extraneous files
Message-ID: <alpine.DEB.1.00.0901200040550.3586@pacific.mpi-cbg.de>
URL: https://gitlist.dev/e/alpine.DEB.1.00.0901200040550.3586%40pacific.mpi-cbg.de
In-Reply-To: <200901191716.59373.bss@iguanasuicide.net>

```
Hi,

On Mon, 19 Jan 2009, Boyd Stephen Smith Jr. wrote:

> I think you mean "No untracked content is removed,...".

As "checkout" is about switching branches, and as Git is very keen on 
avoiding loss of uncommitted changes, I think this comment is utterly 
unnecessary.  Indeed, it is rather annoying: when I read a document the 
other day, that I _had_ to read, and which was full of obvious statements, 
sure enough, I missed the single important half-sentence.

IOW do not clutter the man page with distracting stuff, please, please, 
please.

Ciao,
Dscho

```

## jidanni@jidanni.org, 2009-01-20 00:01

Subject: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <878wp6voar.fsf_-_@jidanni.org>
URL: https://gitlist.dev/e/878wp6voar.fsf_-_%40jidanni.org
In-Reply-To: <alpine.DEB.1.00.0901200040550.3586@pacific.mpi-cbg.de>

```
Signed-off-by: jidanni <jidanni@jidanni.org>
---
OK thanks Johannes.
I'm still worried that there is no exact statement on the fate of the
various different classes of files, but OK, moving this to only a SEE ALSO.

 Documentation/git-checkout.txt |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 9cd5151..6ffb783 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -246,6 +246,9 @@ $ edit frotz
 $ git add frotz
 ------------
 
+SEE ALSO
+--------
+linkgit:git-clean[1]
 
 Author
 ------
-- 
1.6.0.6

```

## Johannes Schindelin, 2009-01-20 00:11

Subject: Re: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <alpine.DEB.1.00.0901200110410.3586@pacific.mpi-cbg.de>
URL: https://gitlist.dev/e/alpine.DEB.1.00.0901200110410.3586%40pacific.mpi-cbg.de
In-Reply-To: <878wp6voar.fsf_-_@jidanni.org>

```
Hi,

On Tue, 20 Jan 2009, jidanni@jidanni.org wrote:

> Signed-off-by: jidanni <jidanni@jidanni.org>
> ---
> OK thanks Johannes.
> I'm still worried that there is no exact statement on the fate of the
> various different classes of files, but OK, moving this to only a SEE ALSO.

You completely misread me.  So I will say it out directly: I think no 
patch is needed.

Hth,
Dscho

```

## Boyd Stephen Smith Jr., 2009-01-20 00:54

Subject: Re: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <200901191854.58029.bss@iguanasuicide.net>
URL: https://gitlist.dev/e/200901191854.58029.bss%40iguanasuicide.net
In-Reply-To: <alpine.DEB.1.00.0901200110410.3586@pacific.mpi-cbg.de>

```
On Monday 19 January 2009, Johannes Schindelin <Johannes.Schindelin@gmx.de> 
wrote about 'Re: [PATCH,v4] git-checkout(1): mention fate of extraneous 
files':
>On Tue, 20 Jan 2009, jidanni@jidanni.org wrote:
>> Signed-off-by: jidanni <jidanni@jidanni.org>
>> ---
>> OK thanks Johannes.
>> I'm still worried that there is no exact statement on the fate of the
>> various different classes of files, but OK, moving this to only a SEE
>> ALSO.
>
>You completely misread me.  So I will say it out directly: I think no
>patch is needed.

I think some users will expect to get a clean checkout when simply 
doing "git checkout <branch>".  It would be nice for the documentation 
mention that is not the case, and reference the tool that helps get the 
tree into that state.  Just my opinion, though.

It seems natural to me for this to be mentioned in the 'git checkout' 
documentation.  Perhaps there's a better place?
-- 
Boyd Stephen Smith Jr.                     ,= ,-_-. =. 
bss@iguanasuicide.net                     ((_/)o o(\_))
ICQ: 514984 YM/AIM: DaTwinkDaddy           `-'(. .)`-' 
http://iguanasuicide.net/                      \_/     

```

## Junio C Hamano, 2009-01-20 03:35

Subject: Re: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <7vy6x6odiw.fsf@gitster.siamese.dyndns.org>
URL: https://gitlist.dev/e/7vy6x6odiw.fsf%40gitster.siamese.dyndns.org
In-Reply-To: <200901191854.58029.bss@iguanasuicide.net>

```
"Boyd Stephen Smith Jr." <bss@iguanasuicide.net> writes:

> I think some users will expect to get a clean checkout when simply 
> doing "git checkout <branch>".  It would be nice for the documentation 
> mention that is not the case, and reference the tool that helps get the 
> tree into that state.  Just my opinion, though.
>
> It seems natural to me for this to be mentioned in the 'git checkout' 
> documentation.  Perhaps there's a better place?

I think this is probably on the other side of the borderline.

First I was about to agree with you, but the more I think about it, I do
not think it is natural at all to expect "checkout" to behave as if you
did "rm -fr" everything and then "tar xf" over the void.  What other SCM
implements branch switching that way, and what workflow would such a
behaviour help?

We need to draw a line somewhere to avoid cluttering the documentation too
much, and I do not think this is something even a person with CVS
braindamage would get confused about, which is where I think is a
reasonable place to draw that line.

Having said all that, I share a desire to help people who do not have any
prior experience nor knowledge to form a reasonable expectation out of the
system.

For example, a person who does not have a clue on what version control
system is about may think that the contents recorded in a branch is like a
tarball, a version control system is not about helping you make changes
but its _sole_ purpose is to extract one such tarball after another on
demand to let you travel in time.  Running an equivalent of "git clean"
automatically upon checkout may feel as if it is a valid a convenience
feature to deal with files that was in one tarball but not in the new one.
It is not completely implausible that such a person may be confused upon
learning that "checkout" leaves untracked paths intact.  If you start from
a flawed understanding of what problem the system helps you to solve, you
end up with flawed expectations.

It would not help him if you only taught that checkout leaves untracked
paths intact.  You have instead to teach him why you may have, and you
would want to keep, untracked paths in the work tree (i.e. they are build
products and notes you take while developing, iow, files that are
essential during your work, but does not belong to the end product, and
you would want to keep them around even while switching branches because
you may be growing both branches at the same time), and that it is one of
the prime design concern to _any_ command in git not to lose them without
being told.  When a user lacks such a basic understanding of the system,
what it was designed for and what it was designed to do, the user's
expectation will never match what many parts of the system do.  The user
will stay confused.

I've always thought such basic concepts should be covered by the tutorial
and the users are expected to read them before reading about individual
commands, but that approach may not work in practice.  Perhaps a separate
section "Basic Understanding" at the end of each manual page of the
command to cover minimum necessary basics to understand the command might
help.  The section may quote from the tutorial, or written afresh.

But I think that such a basic description should be in a separate section
so that it does not clutter the main text for people who understand the
basics.  Also I fear there will be quite a lot of repetition (e.g. you may
have to repeat that untracked files are unintersting and that is why the
command does not say anything about them in manual pages for "diff",
"grep", "checkout", etc.).  Once it is understood, the user does not need
it to be repeated, but if we want to let the user freely start reading
from anywhere, the repetition cannot be avoided.

```

## Johannes Schindelin, 2009-01-20 10:07

Subject: Re: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <alpine.DEB.1.00.0901201106030.3586@pacific.mpi-cbg.de>
URL: https://gitlist.dev/e/alpine.DEB.1.00.0901201106030.3586%40pacific.mpi-cbg.de
In-Reply-To: <7vy6x6odiw.fsf@gitster.siamese.dyndns.org>

```
Hi,

On Mon, 19 Jan 2009, Junio C Hamano wrote:

> [...] the more I think about it, I do not think it is natural at all to 
> expect "checkout" to behave as if you did "rm -fr" everything and then 
> "tar xf" over the void.  What other SCM implements branch switching that 
> way, and what workflow would such a behaviour help?
> 
> We need to draw a line somewhere to avoid cluttering the documentation 
> too much, and I do not think this is something even a person with CVS 
> braindamage would get confused about, which is where I think is a 
> reasonable place to draw that line.

IIRC both CVS and Subversion allow you to say "$SCM co" with an existing 
working directory, which is then updated (and untracked files are left 
alone, as "$SCM up" always did and should do).

So no, not even people with CVS/SVN braindamage would get confused thusly.

Ciao,
Dscho

```

## jidanni@jidanni.org, 2009-01-20 19:45

Subject: Re: [PATCH,v4] git-checkout(1): mention fate of extraneous files
Message-ID: <87zlhl69tg.fsf@jidanni.org>
URL: https://gitlist.dev/e/87zlhl69tg.fsf%40jidanni.org
In-Reply-To: <7vy6x6odiw.fsf@gitster.siamese.dyndns.org>

```
Thank you all for your responses. I hope one day the git-checkout man
page will document what git-checkout does.

I believe that when classified in terms of their differing fates,
there are two or three different types of files that might be sitting
around in one's working tree at the time a "git checkout comes down on
their heads".

Perhaps a brief table of their different fates might nice to have on
the bottom of the man page.

OK, never mind.

```
