threads / patch / 61353

patchstash: fix "--staged" with binary files

Subject: [PATCH] stash: fix "--staged" with binary files

## tl;dr

4 messages between Apr 22, 2024 and Apr 23, 2024. Diffs are folded; open one to read it.

replies: 3people: 3as markdown or json

Adam Johnson via GitGitGadget· Apr 22, 2024, 10:28 UTC · lore

From: Adam Johnson <me@adamj.eu>

"git stash --staged" would crash with binary files, after saving the stash. This behaviour dates back to the addition of the feature in 41a28eb6c1 (stash: implement '--staged' option for 'push' and 'save', 2021-10-18). Adding the "--binary" option of "diff-tree" fixes this. The "diff-tree" call in stash_patch() also omits "--binary", but that is fine since binary files cannot be selected interactively.

Helped-By: Jeff King <peff@peff.net>
Helped-By: Randall S. Becker <randall.becker@nexbridge.ca>
Signed-off-by: Adam Johnson <me@adamj.eu>
---
    stash: fix "--staged" with binary files

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1722%2Fadamchainz%2Faj%2Fstash-binary-fix-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1722/adamchainz/aj/stash-binary-fix-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1722

 builtin/stash.c  | 4 ++--
 t/t3903-stash.sh | 9 +++++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

Show changes to 2 files +11 −2

builtin/stash.c, t/t3903-stash.sh

diff --git a/builtin/stash.c b/builtin/stash.c
index 062be1fbc07..7751bca868e 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -1205,8 +1205,8 @@ static int stash_staged(struct stash_info *info, struct strbuf *out_patch,
 	}
 
 	cp_diff_tree.git_cmd = 1;
-	strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "-U1", "HEAD",
-		     oid_to_hex(&info->w_tree), "--", NULL);
+	strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "--binary",
+		     "-U1", "HEAD", oid_to_hex(&info->w_tree), "--", NULL);
 	if (pipe_command(&cp_diff_tree, NULL, 0, out_patch, 0, NULL, 0)) {
 		ret = -1;
 		goto done;
diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
index 00db82fb245..a7f71f8126f 100755
--- a/t/t3903-stash.sh
+++ b/t/t3903-stash.sh
@@ -393,6 +393,15 @@ test_expect_success 'stash --staged' '
 	test bar,bar4 = $(cat file),$(cat file2)
 '
 
+test_expect_success 'stash --staged with binary file' '
+	printf "\0" >file &&
+	git add file &&
+	git stash --staged &&
+	git stash pop &&
+	printf "\0" >expect &&
+	test_cmp expect file
+'
+
 test_expect_success 'dont assume push with non-option args' '
 	test_must_fail git stash -q drop 2>err &&
 	test_grep -e "subcommand wasn'\''t specified; '\''push'\'' can'\''t be assumed due to unexpected token '\''drop'\''" err

base-commit: ae3196a5ea84a9e88991d576020cf66512487088

-- 
gitgitgadget

Junio C Hamano· Apr 22, 2024, 19:00 UTC · re: Adam Johnson via GitGitGadget · lore

Re: [PATCH] stash: fix "--staged" with binary files

"Adam Johnson via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Adam Johnson <me@adamj.eu>
>
> "git stash --staged" would crash with binary files, after saving the stash.

"would crash with" -> "errors out when given", probably.

We would be better off reserving the word "crash" to refer to an uncontrolled exit with non-zero status of the command, possibly killed via system signals like SEGV and SIGBUS. In this case, I suspect that you would get an "error:" from underlying apply machinery, which leads the caller to exit with a non-zero status due to an error.

> This behaviour dates back to the addition of the feature in 41a28eb6c1
> (stash: implement '--staged' option for 'push' and 'save', 2021-10-18).

When you find the commit that introduced the problem you are fixing, especially when the author of the commit is still active on the mailing list, it would be nice to give a carbon-copy of the message to them.

> Adding the "--binary" option of "diff-tree" fixes this. The "diff-tree" call
> in stash_patch() also omits "--binary", but that is fine since binary files
> cannot be selected interactively.

I love seeing an explanation like this in a proposed commit log message. It is concise but very clear at the same time. It is so clearly written that anybody who is reasonably familiar with the code does not even need to look at the patch text itself to see what the actual fix would look like.

Very nicely explained.

> Helped-By: Jeff King <peff@peff.net>
> Helped-By: Randall S. Becker <randall.becker@nexbridge.ca>
> Signed-off-by: Adam Johnson <me@adamj.eu>
> ---

Will queue.

Thanks.

Show 31 quoted lines

> diff --git a/builtin/stash.c b/builtin/stash.c
> index 062be1fbc07..7751bca868e 100644
> --- a/builtin/stash.c
> +++ b/builtin/stash.c
> @@ -1205,8 +1205,8 @@ static int stash_staged(struct stash_info *info, struct strbuf *out_patch,
>  	}
>  
>  	cp_diff_tree.git_cmd = 1;
> -	strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "-U1", "HEAD",
> -		     oid_to_hex(&info->w_tree), "--", NULL);
> +	strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "--binary",
> +		     "-U1", "HEAD", oid_to_hex(&info->w_tree), "--", NULL);
>  	if (pipe_command(&cp_diff_tree, NULL, 0, out_patch, 0, NULL, 0)) {
>  		ret = -1;
>  		goto done;
> diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
> index 00db82fb245..a7f71f8126f 100755
> --- a/t/t3903-stash.sh
> +++ b/t/t3903-stash.sh
> @@ -393,6 +393,15 @@ test_expect_success 'stash --staged' '
>  	test bar,bar4 = $(cat file),$(cat file2)
>  '
>  
> +test_expect_success 'stash --staged with binary file' '
> +	printf "\0" >file &&
> +	git add file &&
> +	git stash --staged &&
> +	git stash pop &&
> +	printf "\0" >expect &&
> +	test_cmp expect file
> +'

Adam Johnson· Apr 22, 2024, 20:48 UTC · re: Junio C Hamano · lore

Re: [PATCH] stash: fix "--staged" with binary files

Thank you for the feedback, that was clearly explained. I will try to remember to CC more relevant folks in the future.

On Mon, 22 Apr 2024, at 20:00, Junio C Hamano wrote:

Show 77 quoted lines

> "Adam Johnson via GitGitGadget" <gitgitgadget@gmail.com> writes:
> 
> > From: Adam Johnson <me@adamj.eu>
> >
> > "git stash --staged" would crash with binary files, after saving the stash.
> 
> "would crash with" -> "errors out when given", probably.
> 
> We would be better off reserving the word "crash" to refer to an
> uncontrolled exit with non-zero status of the command, possibly
> killed via system signals like SEGV and SIGBUS.  In this case, I
> suspect that you would get an "error:" from underlying apply
> machinery, which leads the caller to exit with a non-zero status
> due to an error.
> 
> > This behaviour dates back to the addition of the feature in 41a28eb6c1
> > (stash: implement '--staged' option for 'push' and 'save', 2021-10-18).
> 
> When you find the commit that introduced the problem you are fixing,
> especially when the author of the commit is still active on the
> mailing list, it would be nice to give a carbon-copy of the message
> to them.
> 
> > Adding the "--binary" option of "diff-tree" fixes this. The "diff-tree" call
> > in stash_patch() also omits "--binary", but that is fine since binary files
> > cannot be selected interactively.
> 
> I love seeing an explanation like this in a proposed commit log
> message.  It is concise but very clear at the same time.  It is so
> clearly written that anybody who is reasonably familiar with the
> code does not even need to look at the patch text itself to see what
> the actual fix would look like.
> 
> Very nicely explained.
> 
> > Helped-By: Jeff King <peff@peff.net>
> > Helped-By: Randall S. Becker <randall.becker@nexbridge.ca>
> > Signed-off-by: Adam Johnson <me@adamj.eu>
> > ---
> 
> Will queue.
> 
> Thanks.
> 
> > diff --git a/builtin/stash.c b/builtin/stash.c
> > index 062be1fbc07..7751bca868e 100644
> > --- a/builtin/stash.c
> > +++ b/builtin/stash.c
> > @@ -1205,8 +1205,8 @@ static int stash_staged(struct stash_info *info, struct strbuf *out_patch,
> >  }
> >  
> >  cp_diff_tree.git_cmd = 1;
> > - strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "-U1", "HEAD",
> > -      oid_to_hex(&info->w_tree), "--", NULL);
> > + strvec_pushl(&cp_diff_tree.args, "diff-tree", "-p", "--binary",
> > +      "-U1", "HEAD", oid_to_hex(&info->w_tree), "--", NULL);
> >  if (pipe_command(&cp_diff_tree, NULL, 0, out_patch, 0, NULL, 0)) {
> >  ret = -1;
> >  goto done;
> > diff --git a/t/t3903-stash.sh b/t/t3903-stash.sh
> > index 00db82fb245..a7f71f8126f 100755
> > --- a/t/t3903-stash.sh
> > +++ b/t/t3903-stash.sh
> > @@ -393,6 +393,15 @@ test_expect_success 'stash --staged' '
> >  test bar,bar4 = $(cat file),$(cat file2)
> >  '
> >  
> > +test_expect_success 'stash --staged with binary file' '
> > + printf "\0" >file &&
> > + git add file &&
> > + git stash --staged &&
> > + git stash pop &&
> > + printf "\0" >expect &&
> > + test_cmp expect file
> > +'
> 
>

Jeff King· Apr 23, 2024, 21:44 UTC · re: Adam Johnson via GitGitGadget · lore

Re: [PATCH] stash: fix "--staged" with binary files

On Mon, Apr 22, 2024 at 10:28:14AM +0000, Adam Johnson via GitGitGadget wrote:

Show 12 quoted lines

> From: Adam Johnson <me@adamj.eu>
> 
> "git stash --staged" would crash with binary files, after saving the stash.
> This behaviour dates back to the addition of the feature in 41a28eb6c1
> (stash: implement '--staged' option for 'push' and 'save', 2021-10-18).
> Adding the "--binary" option of "diff-tree" fixes this. The "diff-tree" call
> in stash_patch() also omits "--binary", but that is fine since binary files
> cannot be selected interactively.
> 
> Helped-By: Jeff King <peff@peff.net>
> Helped-By: Randall S. Becker <randall.becker@nexbridge.ca>
> Signed-off-by: Adam Johnson <me@adamj.eu>

I had to dig in the archive to remember what I might have helped with. ;)

The patch looks good to me, though one thing I noticed:

Show 8 quoted lines

> +test_expect_success 'stash --staged with binary file' '
> +	printf "\0" >file &&
> +	git add file &&
> +	git stash --staged &&
> +	git stash pop &&
> +	printf "\0" >expect &&
> +	test_cmp expect file
> +'

I wonder if test_cmp would ever have problems with binary files on any platforms (and yes, I was the one who suggested using it). We use "diff" on most platforms, but a few (like old SunOS) set GIT_TEST_CMP to "cmp" because they don't have "diff -u" at all. I'm content to leave it as-is until somebody turns up a platform that complains, and then the escape hatch is "OK, so set GIT_TEST_CMP=cmp".

-Peff