Re: [PATCH v3] show-index: fix uninitialized hash function

> As stated in the docs, show-index should use SHA1 as the default hash algorithm
> when run outsize of a repository.  However, 'the_hash_algo' is currently left
> uninitialized if we are not in a repository and no explicit hash function is
> specified, causing a crash.  Fix it by falling back to SHA1 when it is found
> uninitialized. Also add test that verifies this behaviour.

> Signed-off-by: Abhijeet Sonar <abhijeet.nkt@gmail.com>
> ---
>  builtin/show-index.c   | 3 +++
>  t/t5300-pack-object.sh | 4 ++++
>  2 files changed, 7 insertions(+)
>
> diff --git a/builtin/show-index.c b/builtin/show-index.c
> index f164c01bbe..978ae70470 100644
> --- a/builtin/show-index.c
> +++ b/builtin/show-index.c
> @@ -38,6 +38,9 @@ int cmd_show_index(int argc,
>  		repo_set_hash_algo(the_repository, hash_algo);
>  	}
>
> +	if (!the_hash_algo)
> +		repo_set_hash_algo(the_repository, GIT_HASH_SHA1);
> +
>  	hashsz = the_hash_algo->rawsz;
>
>  	if (fread(top_index, 2 * 4, 1, stdin) != 1)
> diff --git a/t/t5300-pack-object.sh b/t/t5300-pack-object.sh
> index 3b9dae331a..51fed26cc4 100755
> --- a/t/t5300-pack-object.sh
> +++ b/t/t5300-pack-object.sh
> @@ -523,6 +523,10 @@ test_expect_success 'index-pack --strict <pack> works in non-repo' '
>  	test_path_is_file foo.idx
>  '
>
> +test_expect_success SHA1 'show-index works OK outside a repository' '
> +	nongit git show-index <foo.idx
> +'
> +
>  test_expect_success !PTHREADS,!FAIL_PREREQS \
>  	'index-pack --threads=N or pack.threads=N warns when no pthreads' '
>  	test_must_fail git index-pack --threads=2 2>err &&
> --
> 2.47.0.107.g34b6ce9b30