Subject: Re: [PATCH 5/5] branch: show "HEAD detached" first under reverse sort

From: Junio C Hamano <[email-masked]>
Date: Wed, 06 Jan 2021 15:49:04 -0800

Ævar Arnfjörð Bjarmason  <[email-masked]> writes:

>  	struct atom_value *va, *vb;
>  	int cmp;
> +	int cmp_detached_head = 0;
>  	cmp_type cmp_type = used_atom[s->atom].type;
>  	int (*cmp_fn)(const char *, const char *);
>  	struct strbuf err = STRBUF_INIT;
> @@ -2370,6 +2371,7 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
>  	     ^
>  	     (b->kind & FILTER_REFS_DETACHED_HEAD))) {
>  		cmp = compare_detached_head(a, b);
> +		cmp_detached_head = 1;
>  	} else if (s->version)
>  		cmp = versioncmp(va->s, vb->s);
>  	else if (cmp_type == FIELD_STR)
> @@ -2383,7 +2385,7 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
>  			cmp = 1;
>  	}
>  
> -	return (s->reverse) ? -cmp : cmp;
> +	return (s->reverse && !cmp_detached_head) ? -cmp : cmp;
>  }

OK.  Other criteria would honor the "reverse" bit, but when we work
on the set that includes "HEAD" ref (which only happens when "branch -l"
deals with a detached head), it always tries to sort it before all other
refs, regardless of the reverse bit.  Makes sense.

>  static int compare_refs(const void *a_, const void *b_, void *ref_sorting)
> diff --git a/t/t3203-branch-output.sh b/t/t3203-branch-output.sh
> index 8f53b081365..5e0577d5c7f 100755
> --- a/t/t3203-branch-output.sh
> +++ b/t/t3203-branch-output.sh
> @@ -221,10 +221,10 @@ test_expect_success 'git branch `--sort=[-]objectsize` option' '
>  	test_i18ncmp expect actual &&
>  
>  	cat >expect <<-\EOF &&
> +	* (HEAD detached from fromtag)
>  	  branch-one
>  	  main
>  	  branch-two
> -	* (HEAD detached from fromtag)
>  	EOF
>  	git branch --sort=-objectsize >actual &&
>  	test_i18ncmp expect actual
> @@ -241,10 +241,10 @@ test_expect_success 'git branch `--sort=[-]type` option' '
>  	test_i18ncmp expect actual &&
>  
>  	cat >expect <<-\EOF &&
> +	* (HEAD detached from fromtag)
>  	  branch-one
>  	  branch-two
>  	  main
> -	* (HEAD detached from fromtag)
>  	EOF
>  	git branch --sort=-type >actual &&
>  	test_i18ncmp expect actual
> @@ -261,10 +261,10 @@ test_expect_success 'git branch `--sort=[-]version:refname` option' '
>  	test_i18ncmp expect actual &&
>  
>  	cat >expect <<-\EOF &&
> +	* (HEAD detached from fromtag)
>  	  main
>  	  branch-two
>  	  branch-one
> -	* (HEAD detached from fromtag)
>  	EOF
>  	git branch --sort=-version:refname >actual &&
>  	test_i18ncmp expect actual