Subject: Re: [PATCH v5 5/5] apply: fix uninitialized hash function

From: Patrick Steinhardt <[email-masked]>
Date: Tue, 21 May 2024 09:58:08 +0200

On Mon, May 20, 2024 at 04:14:34PM -0700, Junio C Hamano wrote:
> "git apply" can work outside a repository as a better "GNU patch",
> but when it does so, it still assumed that it can access
> the_hash_algo, which is no longer true in the new world order.
> 
> Make sure we explicitly fall back to SHA-1 algorithm for backward
> compatibility.
> 
> Signed-off-by: Junio C Hamano <[email-masked]>
> ---
>  builtin/apply.c         | 4 ++++
>  t/t1517-outside-repo.sh | 2 +-
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/builtin/apply.c b/builtin/apply.c
> index 861a01910c..e9175f820f 100644
> --- a/builtin/apply.c
> +++ b/builtin/apply.c
> @@ -1,6 +1,7 @@
>  #include "builtin.h"
>  #include "gettext.h"
>  #include "repository.h"
> +#include "hash.h"
>  #include "apply.h"
>  
>  static const char * const apply_usage[] = {
> @@ -18,6 +19,9 @@ int cmd_apply(int argc, const char **argv, const char *prefix)
>  	if (init_apply_state(&state, the_repository, prefix))
>  		exit(128);
>  
> +	if (!the_hash_algo)
> +		repo_set_hash_algo(the_repository, GIT_HASH_SHA1);
> +

Do we also want to add a comment here that mentions that we may want to
make this configureable via a command line option, like we have in the
preceding commits?

Patrick

>  	argc = apply_parse_options(argc, argv,
>  				   &state, &force_apply, &options,
>  				   apply_usage);
> diff --git a/t/t1517-outside-repo.sh b/t/t1517-outside-repo.sh
> index 2d8982d61a..557808ffa7 100755
> --- a/t/t1517-outside-repo.sh
> +++ b/t/t1517-outside-repo.sh
> @@ -37,7 +37,7 @@ test_expect_success 'hash-object outside repository (uses SHA-1)' '
>  	test_cmp hash.expect hash.actual
>  '
>  
> -test_expect_failure 'apply a patch outside repository' '
> +test_expect_success 'apply a patch outside repository' '
>  	(
>  		cd non-repo &&
>  		cp ../nums.old nums &&
> -- 
> 2.45.1-216-g4365c6fcf9
> 
>