# [PATCH] git-rebase.txt: add another hook to the hooks section, and explain more

6 messages from 2020-04-03 to 2020-04-05. Participants: Elijah Newren via GitGitGadget, Junio C Hamano, Elijah Newren, Phillip Wood.
Thread: https://gitlist.dev/t/53162

## Elijah Newren via GitGitGadget, 2020-04-03 04:35

Subject: [PATCH] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <pull.749.git.git.1585888520572.gitgitgadget@gmail.com>
URL: https://gitlist.dev/e/pull.749.git.git.1585888520572.gitgitgadget%40gmail.com

```
From: Elijah Newren <newren@gmail.com>

For more discussion about these hooks, their history relative to rebase,
and logical consistency between different types of operations, see
  https://lore.kernel.org/git/CABPp-BG0bFKUage5cN_2yr2DkmS04W2Z9Pg5WcROqHznV3XBdw@mail.gmail.com/
and the links to some threads referenced therein.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
    git-rebase.txt: add another hook to the hooks section, and explain more
    
    I'm particularly interested in opinions on the last sentence added to
    the manpage, which is based on the thread mentioned in the commit
    message.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-749%2Fnewren%2Frebase-and-hooks-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-749/newren/rebase-and-hooks-v1
Pull-Request: https://github.com/git/git/pull/749

 Documentation/git-rebase.txt | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index f7a6033607f..5c518ca0ccf 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -684,9 +684,15 @@ Hooks
 ~~~~~
 
 The apply backend has not traditionally called the post-commit hook,
-while the merge backend has.  However, this was by accident of
-implementation rather than by design.  Both backends should have the
-same behavior, though it is not clear which one is correct.
+while the merge backend has.  In contrast, the apply backend has
+traditionally called the post-checkout hook while the merge backend
+has not.  However, the calling of these hooks in both cases was by
+accident of implementation rather than by design (both backends were
+originally implemented as shell scripts and happened to invoke other
+commands like 'git checkout' or 'git commit' that would call the
+hooks).  Both backends should have the same behavior, though it is not
+entirely clear which, if any, is correct.  We will likely remove both
+of these hooks in the future.
 
 Interruptability
 ~~~~~~~~~~~~~~~~

base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
-- 
gitgitgadget

```

## Junio C Hamano, 2020-04-03 19:35

Subject: Re: [PATCH] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <xmqqk12wz7jv.fsf@gitster.c.googlers.com>
URL: https://gitlist.dev/e/xmqqk12wz7jv.fsf%40gitster.c.googlers.com
In-Reply-To: <pull.749.git.git.1585888520572.gitgitgadget@gmail.com>

```
"Elijah Newren via GitGitGadget" <gitgitgadget@gmail.com> writes:

>  The apply backend has not traditionally called the post-commit hook,
> +while the merge backend has.  In contrast, the apply backend has
> +traditionally called the post-checkout hook while the merge backend
> +has not.  However, the calling of these hooks in both cases was by
> +accident of implementation rather than by design (both backends were
> +originally implemented as shell scripts and happened to invoke other
> +commands like 'git checkout' or 'git commit' that would call the
> +hooks).  Both backends should have the same behavior, though it is not
> +entirely clear which, if any, is correct.  We will likely remove both
> +of these hooks in the future.

I'd phrase, instead of "remove", "stop calling from 'git rebase'".
These hooks will still be called from their intended context ;-)

```

## Elijah Newren, 2020-04-03 19:52

Subject: Re: [PATCH] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <CABPp-BHQ9NSaocWEC9GGN4xD7sqi6MrtF98gDgZ5O5fhYYgwbw@mail.gmail.com>
URL: https://gitlist.dev/e/CABPp-BHQ9NSaocWEC9GGN4xD7sqi6MrtF98gDgZ5O5fhYYgwbw%40mail.gmail.com
In-Reply-To: <xmqqk12wz7jv.fsf@gitster.c.googlers.com>

```
On Fri, Apr 3, 2020 at 12:35 PM Junio C Hamano <gitster@pobox.com> wrote:
>
> "Elijah Newren via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
> >  The apply backend has not traditionally called the post-commit hook,
> > +while the merge backend has.  In contrast, the apply backend has
> > +traditionally called the post-checkout hook while the merge backend
> > +has not.  However, the calling of these hooks in both cases was by
> > +accident of implementation rather than by design (both backends were
> > +originally implemented as shell scripts and happened to invoke other
> > +commands like 'git checkout' or 'git commit' that would call the
> > +hooks).  Both backends should have the same behavior, though it is not
> > +entirely clear which, if any, is correct.  We will likely remove both
> > +of these hooks in the future.
>
> I'd phrase, instead of "remove", "stop calling from 'git rebase'".
> These hooks will still be called from their intended context ;-)

Makes sense; I'll update it.

```

## Elijah Newren via GitGitGadget, 2020-04-04 01:30

Subject: [PATCH v2] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <pull.749.v2.git.git.1585963816430.gitgitgadget@gmail.com>
URL: https://gitlist.dev/e/pull.749.v2.git.git.1585963816430.gitgitgadget%40gmail.com
In-Reply-To: <pull.749.git.git.1585888520572.gitgitgadget@gmail.com>

```
From: Elijah Newren <newren@gmail.com>

For more discussion about these hooks, their history relative to rebase,
and logical consistency between different types of operations, see
  https://lore.kernel.org/git/CABPp-BG0bFKUage5cN_2yr2DkmS04W2Z9Pg5WcROqHznV3XBdw@mail.gmail.com/
and the links to some threads referenced therein.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
    git-rebase.txt: add another hook to the hooks section, and explain more
    
    Changes since v1:
    
     * Updated the wording of the last sentence as per Junio's suggestion.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-749%2Fnewren%2Frebase-and-hooks-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-749/newren/rebase-and-hooks-v2
Pull-Request: https://github.com/git/git/pull/749

Range-diff vs v1:

 1:  29a1ff520ba ! 1:  45a5c1c1ff9 git-rebase.txt: add another hook to the hooks section, and explain more
     @@ Documentation/git-rebase.txt: Hooks
      +originally implemented as shell scripts and happened to invoke other
      +commands like 'git checkout' or 'git commit' that would call the
      +hooks).  Both backends should have the same behavior, though it is not
     -+entirely clear which, if any, is correct.  We will likely remove both
     -+of these hooks in the future.
     ++entirely clear which, if any, is correct.  We will likely make rebase
     ++stop calling either of these hooks in the future.
       
       Interruptability
       ~~~~~~~~~~~~~~~~


 Documentation/git-rebase.txt | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index f7a6033607f..5e0fcd4e9bd 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -684,9 +684,15 @@ Hooks
 ~~~~~
 
 The apply backend has not traditionally called the post-commit hook,
-while the merge backend has.  However, this was by accident of
-implementation rather than by design.  Both backends should have the
-same behavior, though it is not clear which one is correct.
+while the merge backend has.  In contrast, the apply backend has
+traditionally called the post-checkout hook while the merge backend
+has not.  However, the calling of these hooks in both cases was by
+accident of implementation rather than by design (both backends were
+originally implemented as shell scripts and happened to invoke other
+commands like 'git checkout' or 'git commit' that would call the
+hooks).  Both backends should have the same behavior, though it is not
+entirely clear which, if any, is correct.  We will likely make rebase
+stop calling either of these hooks in the future.
 
 Interruptability
 ~~~~~~~~~~~~~~~~

base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
-- 
gitgitgadget

```

## Phillip Wood, 2020-04-04 09:33

Subject: Re: [PATCH v2] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <7c1cf1dd-3f70-0c57-ad4f-44453ed565a6@gmail.com>
URL: https://gitlist.dev/e/7c1cf1dd-3f70-0c57-ad4f-44453ed565a6%40gmail.com
In-Reply-To: <pull.749.v2.git.git.1585963816430.gitgitgadget@gmail.com>

```
Hi Elijah

On 04/04/2020 02:30, Elijah Newren via GitGitGadget wrote:
> From: Elijah Newren <newren@gmail.com>
> 
> For more discussion about these hooks, their history relative to rebase,
> and logical consistency between different types of operations, see
>    https://lore.kernel.org/git/CABPp-BG0bFKUage5cN_2yr2DkmS04W2Z9Pg5WcROqHznV3XBdw@mail.gmail.com/
> and the links to some threads referenced therein.
> 
> Signed-off-by: Elijah Newren <newren@gmail.com>
> ---
>      git-rebase.txt: add another hook to the hooks section, and explain more
>      
>      Changes since v1:
>      
>       * Updated the wording of the last sentence as per Junio's suggestion.
> 
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-749%2Fnewren%2Frebase-and-hooks-v2
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-749/newren/rebase-and-hooks-v2
> Pull-Request: https://github.com/git/git/pull/749
> 
> Range-diff vs v1:
> 
>   1:  29a1ff520ba ! 1:  45a5c1c1ff9 git-rebase.txt: add another hook to the hooks section, and explain more
>       @@ Documentation/git-rebase.txt: Hooks
>        +originally implemented as shell scripts and happened to invoke other
>        +commands like 'git checkout' or 'git commit' that would call the
>        +hooks).  Both backends should have the same behavior, though it is not
>       -+entirely clear which, if any, is correct.  We will likely remove both
>       -+of these hooks in the future.
>       ++entirely clear which, if any, is correct.  We will likely make rebase
>       ++stop calling either of these hooks in the future.
>         
>         Interruptability
>         ~~~~~~~~~~~~~~~~
> 
> 
>   Documentation/git-rebase.txt | 12 +++++++++---
>   1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
> index f7a6033607f..5e0fcd4e9bd 100644
> --- a/Documentation/git-rebase.txt
> +++ b/Documentation/git-rebase.txt
> @@ -684,9 +684,15 @@ Hooks
>   ~~~~~
>   
>   The apply backend has not traditionally called the post-commit hook,
> -while the merge backend has.  However, this was by accident of
> -implementation rather than by design.  Both backends should have the
> -same behavior, though it is not clear which one is correct.
> +while the merge backend has.  In contrast, the apply backend has
> +traditionally called the post-checkout hook while the merge backend
> +has not. 

This is not correct - both backends call the post-checkout hook, but the 
merge backend suppresses any output from it - see 
https://public-inbox.org/git/6c413abc-f48d-5a02-ac8b-09a0fa80b98d@gmail.com/

Best Wishes

Phillip

> However, the calling of these hooks in both cases was by
> +accident of implementation rather than by design (both backends were
> +originally implemented as shell scripts and happened to invoke other
> +commands like 'git checkout' or 'git commit' that would call the
> +hooks).  Both backends should have the same behavior, though it is not
> +entirely clear which, if any, is correct.  We will likely make rebase
> +stop calling either of these hooks in the future.
>   
>   Interruptability
>   ~~~~~~~~~~~~~~~~
> 
> base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
> 

```

## Elijah Newren via GitGitGadget, 2020-04-05 00:00

Subject: [PATCH v3] git-rebase.txt: add another hook to the hooks section, and explain more
Message-ID: <pull.749.v3.git.git.1586044818132.gitgitgadget@gmail.com>
URL: https://gitlist.dev/e/pull.749.v3.git.git.1586044818132.gitgitgadget%40gmail.com
In-Reply-To: <pull.749.v2.git.git.1585963816430.gitgitgadget@gmail.com>

```
From: Elijah Newren <newren@gmail.com>

For more discussion about these hooks, their history relative to rebase,
and logical consistency between different types of operations, see
  https://lore.kernel.org/git/CABPp-BG0bFKUage5cN_2yr2DkmS04W2Z9Pg5WcROqHznV3XBdw@mail.gmail.com/
and the links to some threads referenced therein.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
    git-rebase.txt: add another hook to the hooks section, and explain more
    
    Changes since v2:
    
     * Corrections to the text pointed out by Phillip.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-749%2Fnewren%2Frebase-and-hooks-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-749/newren/rebase-and-hooks-v3
Pull-Request: https://github.com/git/git/pull/749

Range-diff vs v2:

 1:  45a5c1c1ff9 ! 1:  22fb6ff7080 git-rebase.txt: add another hook to the hooks section, and explain more
     @@ Documentation/git-rebase.txt: Hooks
      -while the merge backend has.  However, this was by accident of
      -implementation rather than by design.  Both backends should have the
      -same behavior, though it is not clear which one is correct.
     -+while the merge backend has.  In contrast, the apply backend has
     -+traditionally called the post-checkout hook while the merge backend
     -+has not.  However, the calling of these hooks in both cases was by
     -+accident of implementation rather than by design (both backends were
     -+originally implemented as shell scripts and happened to invoke other
     -+commands like 'git checkout' or 'git commit' that would call the
     -+hooks).  Both backends should have the same behavior, though it is not
     -+entirely clear which, if any, is correct.  We will likely make rebase
     -+stop calling either of these hooks in the future.
     ++while the merge backend has.  Both have called the post-checkout hook,
     ++though the merge backend has squelched its output.  Further, both
     ++backends only call the post-checkout hook with the starting point
     ++commit of the rebase, not the intermediate commits nor the final
     ++commit.  In each case, the calling of these hooks was by accident of
     ++implementation rather than by design (both backends were originally
     ++implemented as shell scripts and happened to invoke other commands
     ++like 'git checkout' or 'git commit' that would call the hooks).  Both
     ++backends should have the same behavior, though it is not entirely
     ++clear which, if any, is correct.  We will likely make rebase stop
     ++calling either of these hooks in the future.
       
       Interruptability
       ~~~~~~~~~~~~~~~~


 Documentation/git-rebase.txt | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index f7a6033607f..5a756b5b3a6 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -684,9 +684,17 @@ Hooks
 ~~~~~
 
 The apply backend has not traditionally called the post-commit hook,
-while the merge backend has.  However, this was by accident of
-implementation rather than by design.  Both backends should have the
-same behavior, though it is not clear which one is correct.
+while the merge backend has.  Both have called the post-checkout hook,
+though the merge backend has squelched its output.  Further, both
+backends only call the post-checkout hook with the starting point
+commit of the rebase, not the intermediate commits nor the final
+commit.  In each case, the calling of these hooks was by accident of
+implementation rather than by design (both backends were originally
+implemented as shell scripts and happened to invoke other commands
+like 'git checkout' or 'git commit' that would call the hooks).  Both
+backends should have the same behavior, though it is not entirely
+clear which, if any, is correct.  We will likely make rebase stop
+calling either of these hooks in the future.
 
 Interruptability
 ~~~~~~~~~~~~~~~~

base-commit: 274b9cc25322d9ee79aa8e6d4e86f0ffe5ced925
-- 
gitgitgadget

```
