Re: [PATCH v4 10/12] ref-filter: introduce remote_ref_atom_parser()

[Eric Sunshine <sunshine@sunshineco.com>]

This is a re-send of patch 10/12 on Karthik's behalf to give other
reviewers a chance at it. The original did not make it to the mailing
list since it contained a rather large binary resource Karthik
accidentally included in the commit (which has been stripped from
this re-send).

On Sun, Jan 31, 2016 at 11:12:54PM +0530, Karthik Nayak wrote:
> Introduce remote_ref_atom_parser() which will parse the '%(upstream)'
> and '%(push)' atoms and store information into the 'used_atom'
> structure based on the modifiers used along with the corresponding
> atom.
> 
> Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
> Helped-by: Eric Sunshine <sunshine@sunshineco.com>
> Signed-off-by: Karthik Nayak <Karthik.188@gmail.com>
> ---
>  ref-filter.c  | 103 ++++++++++++++++++++++++++++++++++------------------------
>  test-fake-ssh | Bin 0 -> 4668264 bytes
>  2 files changed, 61 insertions(+), 42 deletions(-)
>  create mode 100755 test-fake-ssh
> 
> diff --git a/ref-filter.c b/ref-filter.c
> index 58d433f..99c152d 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -37,6 +37,8 @@ static struct used_atom {
>  	union {
>  		char color[COLOR_MAXLEN];
>  		struct align align;
> +		enum { RR_NORMAL, RR_SHORTEN, RR_TRACK, RR_TRACKSHORT }
> +			remote_ref;
>  	} u;
>  } *used_atom;
>  static int used_atom_cnt, need_tagged, need_symref;
> @@ -50,6 +52,20 @@ static void color_atom_parser(struct used_atom *atom, const char *color_value)
>  		die(_("invalid color value: %s"), atom->u.color);
>  }
>  
> +static void remote_ref_atom_parser(struct used_atom *atom, const char *arg)
> +{
> +	if (!arg) {
> +		atom->u.remote_ref = RR_NORMAL;
> +	} else if (!strcmp(arg, "short"))
> +		atom->u.remote_ref = RR_SHORTEN;
> +	else if (!strcmp(arg, "track"))
> +		atom->u.remote_ref = RR_TRACK;
> +	else if (!strcmp(arg, "trackshort"))
> +		atom->u.remote_ref = RR_TRACKSHORT;
> +	else
> +		die(_("unrecognized format: %%(%s)"), atom->name);
> +}
> +
>  static align_type parse_align_position(const char *s)
>  {
>  	if (!strcmp(s, "right"))
> @@ -132,8 +148,8 @@ static struct {
>  	{ "subject" },
>  	{ "body" },
>  	{ "contents" },
> -	{ "upstream" },
> -	{ "push" },
> +	{ "upstream", FIELD_STR, remote_ref_atom_parser },
> +	{ "push", FIELD_STR, remote_ref_atom_parser },
>  	{ "symref" },
>  	{ "flag" },
>  	{ "HEAD" },
> @@ -839,6 +855,43 @@ static const char *strip_ref_components(const char *refname, const char *nr_arg)
>  	return start;
>  }
>  
> +static void fill_remote_ref_details(struct used_atom *atom, const char *refname,
> +				    struct branch *branch, const char **s)
> +{
> +	int num_ours, num_theirs;
> +	if (atom->u.remote_ref == RR_SHORTEN)
> +		*s = shorten_unambiguous_ref(refname, warn_ambiguous_refs);
> +	else if (atom->u.remote_ref == RR_TRACK) {
> +		if (stat_tracking_info(branch, &num_ours,
> +				       &num_theirs, NULL))
> +			return;
> +
> +		if (!num_ours && !num_theirs)
> +			*s = "";
> +		else if (!num_ours)
> +			*s = xstrfmt("[behind %d]", num_theirs);
> +		else if (!num_theirs)
> +			*s = xstrfmt("[ahead %d]", num_ours);
> +		else
> +			*s = xstrfmt("[ahead %d, behind %d]",
> +				     num_ours, num_theirs);
> +	} else if (atom->u.remote_ref == RR_TRACKSHORT) {
> +		if (stat_tracking_info(branch, &num_ours,
> +				       &num_theirs, NULL))
> +			return;
> +
> +		if (!num_ours && !num_theirs)
> +			*s = "=";
> +		else if (!num_ours)
> +			*s = "<";
> +		else if (!num_theirs)
> +			*s = ">";
> +		else
> +			*s = "<>";
> +	} else /* RR_NORMAL */
> +		*s = refname;
> +}
> +
>  /*
>   * Parse the object referred by ref, and grab needed value.
>   */
> @@ -890,8 +943,9 @@ static void populate_value(struct ref_array_item *ref)
>  			branch = branch_get(branch_name);
>  
>  			refname = branch_get_upstream(branch, NULL);
> -			if (!refname)
> -				continue;
> +			if (refname)
> +				fill_remote_ref_details(atom, refname, branch, &v->s);
> +			continue;
>  		} else if (starts_with(name, "push")) {
>  			const char *branch_name;
>  			if (!skip_prefix(ref->refname, "refs/heads/",
> @@ -902,6 +956,8 @@ static void populate_value(struct ref_array_item *ref)
>  			refname = branch_get_push(branch, NULL);
>  			if (!refname)
>  				continue;
> +			fill_remote_ref_details(atom, refname, branch, &v->s);
> +			continue;
>  		} else if (starts_with(name, "color:")) {
>  			v->s = atom->u.color;
>  			continue;
> @@ -943,7 +999,6 @@ static void populate_value(struct ref_array_item *ref)
>  
>  		formatp = strchr(name, ':');
>  		if (formatp) {
> -			int num_ours, num_theirs;
>  			const char *arg;
>  
>  			formatp++;
> @@ -952,43 +1007,7 @@ static void populate_value(struct ref_array_item *ref)
>  						      warn_ambiguous_refs);
>  			else if (skip_prefix(formatp, "strip=", &arg))
>  				refname = strip_ref_components(refname, arg);
> -			else if (!strcmp(formatp, "track") &&
> -				 (starts_with(name, "upstream") ||
> -				  starts_with(name, "push"))) {
> -
> -				if (stat_tracking_info(branch, &num_ours,
> -						       &num_theirs, NULL))
> -					continue;
> -
> -				if (!num_ours && !num_theirs)
> -					v->s = "";
> -				else if (!num_ours)
> -					v->s = xstrfmt("[behind %d]", num_theirs);
> -				else if (!num_theirs)
> -					v->s = xstrfmt("[ahead %d]", num_ours);
> -				else
> -					v->s = xstrfmt("[ahead %d, behind %d]",
> -						       num_ours, num_theirs);
> -				continue;
> -			} else if (!strcmp(formatp, "trackshort") &&
> -				   (starts_with(name, "upstream") ||
> -				    starts_with(name, "push"))) {
> -				assert(branch);
> -
> -				if (stat_tracking_info(branch, &num_ours,
> -							&num_theirs, NULL))
> -					continue;
> -
> -				if (!num_ours && !num_theirs)
> -					v->s = "=";
> -				else if (!num_ours)
> -					v->s = "<";
> -				else if (!num_theirs)
> -					v->s = ">";
> -				else
> -					v->s = "<>";
> -				continue;
> -			} else
> +			else
>  				die("unknown %.*s format %s",
>  				    (int)(formatp - name), name, formatp);
>  		}