[PATCH v4 0/10] port tag.c to use ref-filter APIs

[PATCH v4 0/10] port tag.c to use ref-filter APIs

[Karthik Nayak]

This is part of my GSoC project to unify git tag -l, git branch -l,
git for-each-ref.  This patch series is continued from: Git (next)
https://github.com/git/git/commit/bf5418f49ff0cebc6e5ce04ad1417e1a47c81b61

Version 3 can be found here
http://thread.gmane.org/gmane.comp.version-control.git/274168

Changes from v3:

[01/10]: Changed the whole implementation as per Junio's Suggestion.
Also fixed parts where the code was wrong, as per Matthieu's and
Eric's suggestion.

[04/10]: Small changes in comments and line wrapping.

[05/10]: Include more tests, better comments and refactored code.

[06/10]: Improvement in comments.

[09/10]: Change the tests to not fallback to default values.
Introduce "for_each_tag_ref_fullpath()" which iterates through tags
without stripping the same.

[10/10]: Improvements in comments.

Set of commits:

[PATCH v4 01/10] ref-filter: add option to align atoms to the left
[PATCH v4 02/10] ref-filter: make the 'color' use
[PATCH v4 03/10] ref-filter: add option to filter only tags
[PATCH v4 04/10] ref-filter: support printing N lines from tag
[PATCH v4 05/10] ref-filter: add support to sort by version
[PATCH v4 06/10] ref-filter: add option to match literal pattern
[PATCH v4 07/10] tag.c: use 'ref-filter' data structures
[PATCH v4 08/10] tag.c: use 'ref-filter' APIs
[PATCH v4 09/10] tag.c: implement '--format' option
[PATCH v4 10/10] tag.c: implement '--merged' and '--no-merged'

[PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Add a new atom "align" and support %(align:X) where X is a number.
This will align the preceeding atom value to the left followed by
spaces for a total length of X characters. If X is less than the item
size, the entire atom value is printed.

Helped-by: Duy Nguyen <pclouds@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 ref-filter.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++--------------
 ref-filter.h |  6 ++++
 2 files changed, 77 insertions(+), 22 deletions(-)

diff --git a/ref-filter.c b/ref-filter.c
index 7561727..3c90ffc 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -10,6 +10,8 @@
 #include "quote.h"
 #include "ref-filter.h"
 #include "revision.h"
+#include "utf8.h"
+#include "git-compat-util.h"
 
 typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
 
@@ -53,6 +55,7 @@ static struct {
 	{ "flag" },
 	{ "HEAD" },
 	{ "color" },
+	{ "align" },
 };
 
 /*
@@ -597,7 +600,8 @@ static inline char *copy_advance(char *dst, const char *src)
 /*
  * Parse the object referred by ref, and grab needed value.
  */
-static void populate_value(struct ref_array_item *ref)
+static void populate_value(struct ref_formatting_state *state,
+			   struct ref_array_item *ref)
 {
 	void *buf;
 	struct object *obj;
@@ -620,7 +624,7 @@ static void populate_value(struct ref_array_item *ref)
 		const char *name = used_atom[i];
 		struct atom_value *v = &ref->value[i];
 		int deref = 0;
-		const char *refname;
+		const char *refname = NULL;
 		const char *formatp;
 		struct branch *branch = NULL;
 
@@ -687,6 +691,18 @@ static void populate_value(struct ref_array_item *ref)
 			else
 				v->s = " ";
 			continue;
+		} else if (starts_with(name, "align:")) {
+			const char *valp = NULL;
+
+			skip_prefix(name, "align:", &valp);
+			if (!valp[0])
+				die(_("no value given with 'align:'"));
+			if (strtoul_ui(valp, 10, &state->pad_to_right))
+				die(_("positive integer expected after ':' in align:%u\n"),
+				    state->pad_to_right);
+			v->pseudo_atom = 1;
+			v->s = "";
+			continue;
 		} else
 			continue;
 
@@ -809,10 +825,15 @@ static void populate_value(struct ref_array_item *ref)
  * Given a ref, return the value for the atom.  This lazily gets value
  * out of the object by calling populate value.
  */
-static void get_ref_atom_value(struct ref_array_item *ref, int atom, struct atom_value **v)
+static void get_ref_atom_value(struct ref_formatting_state *state,
+			       struct ref_array_item *ref, int atom, struct atom_value **v)
 {
-	if (!ref->value) {
-		populate_value(ref);
+	/*
+	 * If the atom is a pseudo_atom then we re-populate the value
+	 * into the ref_formatting_state stucture.
+	 */
+	if (!ref->value || ref->value[atom].pseudo_atom) {
+		populate_value(state, ref);
 		fill_missing_values(ref->value);
 	}
 	*v = &ref->value[atom];
@@ -1150,9 +1171,12 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
 	struct atom_value *va, *vb;
 	int cmp;
 	cmp_type cmp_type = used_atom_type[s->atom];
+	struct ref_formatting_state state;
 
-	get_ref_atom_value(a, s->atom, &va);
-	get_ref_atom_value(b, s->atom, &vb);
+	memset(&state, 0, sizeof(state));
+
+	get_ref_atom_value(&state, a, s->atom, &va);
+	get_ref_atom_value(&state, b, s->atom, &vb);
 	switch (cmp_type) {
 	case FIELD_STR:
 		cmp = strcmp(va->s, vb->s);
@@ -1190,30 +1214,50 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
 	qsort(array->items, array->nr, sizeof(struct ref_array_item *), compare_refs);
 }
 
-static void print_value(struct atom_value *v, int quote_style)
+static void ref_formatting(struct ref_formatting_state *state, struct atom_value *v,
+			   struct strbuf *value)
 {
-	struct strbuf sb = STRBUF_INIT;
-	switch (quote_style) {
+	if (state->pad_to_right) {
+		if (!is_utf8(v->s))
+			strbuf_addf(value, "%-*s", state->pad_to_right, v->s);
+		else {
+			int len = strlen(v->s) - utf8_strwidth(v->s);
+			strbuf_addf(value, "%-*s", state->pad_to_right + len, v->s);
+		}
+	} else
+		strbuf_addf(value, "%s", v->s);
+}
+
+static void print_value(struct ref_formatting_state *state, struct atom_value *v)
+{
+	struct strbuf value = STRBUF_INIT;
+	struct strbuf formatted = STRBUF_INIT;
+
+	if (v->pseudo_atom)
+		return;
+	ref_formatting(state, v, &value);
+
+	switch (state->quote_style) {
 	case QUOTE_NONE:
-		fputs(v->s, stdout);
+		fputs(value.buf, stdout);
 		break;
 	case QUOTE_SHELL:
-		sq_quote_buf(&sb, v->s);
+		sq_quote_buf(&formatted, value.buf);
 		break;
 	case QUOTE_PERL:
-		perl_quote_buf(&sb, v->s);
+		perl_quote_buf(&formatted, value.buf);
 		break;
 	case QUOTE_PYTHON:
-		python_quote_buf(&sb, v->s);
+		python_quote_buf(&formatted, value.buf);
 		break;
 	case QUOTE_TCL:
-		tcl_quote_buf(&sb, v->s);
+		tcl_quote_buf(&formatted, value.buf);
 		break;
 	}
-	if (quote_style != QUOTE_NONE) {
-		fputs(sb.buf, stdout);
-		strbuf_release(&sb);
-	}
+	if (state->quote_style != QUOTE_NONE)
+		fputs(formatted.buf, stdout);
+	strbuf_release(&formatted);
+	strbuf_release(&value);
 }
 
 static int hex1(char ch)
@@ -1257,6 +1301,10 @@ static void emit(const char *cp, const char *ep)
 void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
 {
 	const char *cp, *sp, *ep;
+	struct ref_formatting_state state;
+
+	memset(&state, 0, sizeof(state));
+	state.quote_style = quote_style;
 
 	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
 		struct atom_value *atomv;
@@ -1264,8 +1312,9 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 		ep = strchr(sp, ')');
 		if (cp < sp)
 			emit(cp, sp);
-		get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
-		print_value(atomv, quote_style);
+		get_ref_atom_value(&state, info,
+				   parse_ref_filter_atom(sp + 2, ep), &atomv);
+		print_value(&state, atomv);
 	}
 	if (*cp) {
 		sp = cp + strlen(cp);
@@ -1278,7 +1327,7 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 		if (color_parse("reset", color) < 0)
 			die("BUG: couldn't parse 'reset' as a color");
 		resetv.s = color;
-		print_value(&resetv, quote_style);
+		print_value(&state, &resetv);
 	}
 	putchar('\n');
 }
diff --git a/ref-filter.h b/ref-filter.h
index 6bf27d8..ea2d0e6 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -19,6 +19,7 @@
 struct atom_value {
 	const char *s;
 	unsigned long ul; /* used for sorting when not FIELD_STR */
+	unsigned int pseudo_atom : 1; /*  atoms which aren't placeholders for ref attributes */
 };
 
 struct ref_sorting {
@@ -27,6 +28,11 @@ struct ref_sorting {
 	unsigned reverse : 1;
 };
 
+struct ref_formatting_state {
+	unsigned int pad_to_right; /*pad atoms to the right*/
+	int quote_style;
+};
+
 struct ref_array_item {
 	unsigned char objectname[20];
 	int flag;
-- 
2.4.6

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Junio C Hamano]

Karthik Nayak <karthik.188@gmail.com> writes:

> -	if (!ref->value) {
> -		populate_value(ref);
> +	/*
> +	 * If the atom is a pseudo_atom then we re-populate the value
> +	 * into the ref_formatting_state stucture.
> +	 */
> +	if (!ref->value || ref->value[atom].pseudo_atom) {
> +		populate_value(state, ref);
>  		fill_missing_values(ref->value);

I am not sure why you need to do this.  populate_value() and
fill_missing_values() are fairly heavy-weight operations that are
expected to grab everything necessary from scratch, and that is why
we ensure that we do not call them more than once for each "ref"
with by guarding the calls with "if (!ref->value)".

This change is breaking that basic arrangement, and worse yet, it
forces us re-read everything about that ref, leaking old ref->value.

Why could this be a good idea?

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Junio C Hamano]

Junio C Hamano <gitster@pobox.com> writes:

> Karthik Nayak <karthik.188@gmail.com> writes:
>
>> -	if (!ref->value) {
>> -		populate_value(ref);
>> +	/*
>> +	 * If the atom is a pseudo_atom then we re-populate the value
>> +	 * into the ref_formatting_state stucture.
>> +	 */
>> +	if (!ref->value || ref->value[atom].pseudo_atom) {
>> +		populate_value(state, ref);
>>  		fill_missing_values(ref->value);
>
> I am not sure why you need to do this.  populate_value() and
> fill_missing_values() are fairly heavy-weight operations that are
> expected to grab everything necessary from scratch, and that is why
> we ensure that we do not call them more than once for each "ref"
> with by guarding the calls with "if (!ref->value)".
>
> This change is breaking that basic arrangement, and worse yet, it
> forces us re-read everything about that ref, leaking old ref->value.
>
> Why could this be a good idea?

I think populate_value() should not take state; that is the root
cause of this mistake.

The flow should be:

    - verify_format() looks at the format string and enumerates all
      atoms that will ever be used in the output by calling
      parse_atom() and letting it to fill used_atom[];

    - when ref->value is not yet populated, populate_value() is
      called, just once.  This uses the enumeration in used_atom[]
      and stores computed value to refs->value[atom];

    - show_ref() repeatedly calls find_next() to find the next
      reference to %(...), emits everything before it, and then
      uses the atom value (i.e. ref->value[atom]).

I would expect that the atom value for pseudos like color and align
to be parsed and stored in ref->value in populate_value() when it is
called for the first time for each ref _just once_.

"color:blue" may choose to store "blue" as v->s, and "align:4" may
choose to do "v->ul = 4".

And the code that uses these values should look more like:

	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
		struct atom_value *atomv;

		ep = strchr(sp, ')');
		if (cp < sp)
			emit(cp, sp);
		get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
		if (atomv->is_pseudo)
                	apply_pseudo_state(&state, atomv);
		else
			print_value(&state, atomv);
	}

where apply_pseudo_state() would switch on what kind of pseudo the
atom is and update the state accordingly, i.e. the "state" munging
code you added to populate_value() in this patch.

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Karthik Nayak]

On Sat, Jul 25, 2015 at 4:30 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Junio C Hamano <gitster@pobox.com> writes:
>
>> Karthik Nayak <karthik.188@gmail.com> writes:
>>
>>> -    if (!ref->value) {
>>> -            populate_value(ref);
>>> +    /*
>>> +     * If the atom is a pseudo_atom then we re-populate the value
>>> +     * into the ref_formatting_state stucture.
>>> +     */
>>> +    if (!ref->value || ref->value[atom].pseudo_atom) {
>>> +            populate_value(state, ref);
>>>              fill_missing_values(ref->value);
>>
> I am not sure why you need to do this.  populate_value() and
> fill_missing_values() are fairly heavy-weight operations that are
> expected to grab everything necessary from scratch, and that is why
> we ensure that we do not call them more than once for each "ref"
> with by guarding the calls with "if (!ref->value)".
>
> This change is breaking that basic arrangement, and worse yet, it
> forces us re-read everything about that ref, leaking old ref->value.
>
> Why could this be a good idea?
>

This was required as populate_value() would fill the 'state'  but the 'state'
being a static variable would be lost before printing and hence we would
not have the correct values of the 'state' when printing.

> I think populate_value() should not take state; that is the root
> cause of this mistake.

Yes! agreed. atomv should be a better candidate to hold the formatting values.

>
> The flow should be:
>
>     - verify_format() looks at the format string and enumerates all
>       atoms that will ever be used in the output by calling
>       parse_atom() and letting it to fill used_atom[];
>
>     - when ref->value is not yet populated, populate_value() is
>       called, just once.  This uses the enumeration in used_atom[]
>       and stores computed value to refs->value[atom];
>
>     - show_ref() repeatedly calls find_next() to find the next
>       reference to %(...), emits everything before it, and then
>       uses the atom value (i.e. ref->value[atom]).
>
> I would expect that the atom value for pseudos like color and align
> to be parsed and stored in ref->value in populate_value() when it is
> called for the first time for each ref _just once_.
>
> "color:blue" may choose to store "blue" as v->s, and "align:4" may
> choose to do "v->ul = 4".
>
> And the code that uses these values should look more like:
>
>         for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
>                 struct atom_value *atomv;
>
>                 ep = strchr(sp, ')');
>                 if (cp < sp)
>                         emit(cp, sp);
>                 get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
>                 if (atomv->is_pseudo)
>                         apply_pseudo_state(&state, atomv);
>                 else
>                         print_value(&state, atomv);
>         }
>
> where apply_pseudo_state() would switch on what kind of pseudo the
> atom is and update the state accordingly, i.e. the "state" munging
> code you added to populate_value() in this patch.

This makes more sense, and avoids the repetitive call to populate_value().
Will implement this.
Thanks

-- 
Regards,
Karthik Nayak

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Eric Sunshine]

On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
> Add a new atom "align" and support %(align:X) where X is a number.
> This will align the preceeding atom value to the left followed by

Do you mean "succeeding" or "following" or "next" (or something)
rather than "preceding"?

> spaces for a total length of X characters. If X is less than the item
> size, the entire atom value is printed.

Isn't this a pad-right operation? If so, should this be called
%(padright:X) or %(pad:right:X)?

> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>

Also, it is helpful to reviewers if you include an interdiff at the
bottom of your cover letter showing the changes from one version to
another. You can generate an interdiff with "git diff branchname-v4
branchname-v5", for instance.

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Karthik Nayak]

On Sun, Jul 26, 2015 at 9:38 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> Add a new atom "align" and support %(align:X) where X is a number.
>> This will align the preceeding atom value to the left followed by
>
> Do you mean "succeeding" or "following" or "next" (or something)
> rather than "preceding"?

I meant succeeding, I had just changed that, thanks for telling

>
>> spaces for a total length of X characters. If X is less than the item
>> size, the entire atom value is printed.
>
> Isn't this a pad-right operation? If so, should this be called
> %(padright:X) or %(pad:right:X)?
>

I guess "padright" makes more sense, thanks.

>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>
> Also, it is helpful to reviewers if you include an interdiff at the
> bottom of your cover letter showing the changes from one version to
> another. You can generate an interdiff with "git diff branchname-v4
> branchname-v5", for instance.

I've been working on the same branch, and that's why I didn't really
provide interdiff's, and I kinda worked on the same branch again,
so I wont be giving an interdiff for the next series either, but I'll keep this
in mind and follow it from the forthcoming patch series. Thanks

-- 
Regards,
Karthik Nayak

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Eric Sunshine]

On Sun, Jul 26, 2015 at 12:36 AM, Karthik Nayak <karthik.188@gmail.com> wrote:
> On Sun, Jul 26, 2015 at 9:38 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>> Also, it is helpful to reviewers if you include an interdiff at the
>> bottom of your cover letter showing the changes from one version to
>> another. You can generate an interdiff with "git diff branchname-v4
>> branchname-v5", for instance.
>
> I've been working on the same branch, and that's why I didn't really
> provide interdiff's, and I kinda worked on the same branch again,
> so I wont be giving an interdiff for the next series either, but I'll keep this
> in mind and follow it from the forthcoming patch series. Thanks

You can still provide an interdiff. It is quite likely that you can
find the commit corresponding to v4 in the reflog for that branch (see
git-reflog). Failing that, an easy way to recover the state at v4 is
to create a new branch (from the parent of your current working
branch) and apply the v4 patches which you sent to the mailing list.
If Junio queued v4 in his 'pu' branch, then you can also recover from
there. Once you've recovered the state of v4 using one of the methods
mentioned here (or some other), you can make an interdiff when sending
out v5.

Reviewers do appreciate that you provide a URL to the previous version
and take the time to explain in your cover letter what changed (and
why). Including an interdiff is one more way to ease the review
process, and is also appreciated, so it may be worthwhile to put in
the effort to recover the state of v4 so that you can include an
interdiff with v5. Doing so does require a bit of extra work for you,
but that's work you only need to do *once*, whereas if you don't do
it, then you place the burden on *each* reviewer for *each* version,
which quickly adds up to a lot more work for those reviewing your
submissions.

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Karthik Nayak]

On Sun, Jul 26, 2015 at 11:28 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> On Sun, Jul 26, 2015 at 12:36 AM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> On Sun, Jul 26, 2015 at 9:38 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>>> Also, it is helpful to reviewers if you include an interdiff at the
>>> bottom of your cover letter showing the changes from one version to
>>> another. You can generate an interdiff with "git diff branchname-v4
>>> branchname-v5", for instance.
>>
>> I've been working on the same branch, and that's why I didn't really
>> provide interdiff's, and I kinda worked on the same branch again,
>> so I wont be giving an interdiff for the next series either, but I'll keep this
>> in mind and follow it from the forthcoming patch series. Thanks
>
> You can still provide an interdiff. It is quite likely that you can
> find the commit corresponding to v4 in the reflog for that branch (see
> git-reflog). Failing that, an easy way to recover the state at v4 is
> to create a new branch (from the parent of your current working
> branch) and apply the v4 patches which you sent to the mailing list.
> If Junio queued v4 in his 'pu' branch, then you can also recover from
> there. Once you've recovered the state of v4 using one of the methods
> mentioned here (or some other), you can make an interdiff when sending
> out v5.
>

Haha, I was just thinking about applying my patches and doing it, will
definitely
provide an interdiff.

> Reviewers do appreciate that you provide a URL to the previous version
> and take the time to explain in your cover letter what changed (and
> why). Including an interdiff is one more way to ease the review
> process, and is also appreciated, so it may be worthwhile to put in
> the effort to recover the state of v4 so that you can include an
> interdiff with v5. Doing so does require a bit of extra work for you,
> but that's work you only need to do *once*, whereas if you don't do
> it, then you place the burden on *each* reviewer for *each* version,
> which quickly adds up to a lot more work for those reviewing your
> submissions.

Yes! definitely, I'll make sure that I provide the interdiff, I'll
look at reflog,
thanks a lot. I appreciate how reviewers take time to review code, its a
wonderful process. I will be glad to put in any time to make their process
easier

-- 
Regards,
Karthik Nayak

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Matthieu Moy]

Karthik Nayak <karthik.188@gmail.com> writes:

> I've been working on the same branch, and that's why I didn't really
> provide interdiff's,

You can keep working on the same branch and tag versions you send to the
list. "This state is what I sent to the list as vX" is something that does not
change in time hence a tag avoids mistakenly changing it.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Duy Nguyen]

On Sun, Jul 26, 2015 at 11:08 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> You can generate an interdiff with "git diff branchname-v4
> branchname-v5", for instance.

Off topic. But what stops me from doing this often is it creates a big
mess in "git tag -l". Do we have an option to hide away some
"insignificant:" tags? reflog might be an option if we have something
like foo@{/v2} to quickly retrieve the reflog entry whose message
contains "v2".
-- 
Duy

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Jacob Keller]

On Sun, Jul 26, 2015 at 5:39 PM, Duy Nguyen <pclouds@gmail.com> wrote:
> On Sun, Jul 26, 2015 at 11:08 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>> You can generate an interdiff with "git diff branchname-v4
>> branchname-v5", for instance.
>
> Off topic. But what stops me from doing this often is it creates a big
> mess in "git tag -l". Do we have an option to hide away some
> "insignificant:" tags? reflog might be an option if we have something
> like foo@{/v2} to quickly retrieve the reflog entry whose message
> contains "v2".
> --
> Duy
> --
> To unsubscribe from this list: send the line "unsubscribe git" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

You can normally find the previous commit via the reflog. Various
changes to the settings can make the reflog be maintained for longer
if you have longer lived patch series. That's how I would suggest it,
rather than branches, as I tend not to keep old versions around on
separate tags or branches.

The problem with "foo@{/v2}" is that people don't always keep values
inside the message it self, but maybe "foo@{/pattern}" would be a
useful extension?

Regards,
Jake

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Duy Nguyen]

On Mon, Jul 27, 2015 at 2:39 PM, Jacob Keller <jacob.keller@gmail.com> wrote:
> On Sun, Jul 26, 2015 at 5:39 PM, Duy Nguyen <pclouds@gmail.com> wrote:
>> On Sun, Jul 26, 2015 at 11:08 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>>> You can generate an interdiff with "git diff branchname-v4
>>> branchname-v5", for instance.
>>
>> Off topic. But what stops me from doing this often is it creates a big
>> mess in "git tag -l". Do we have an option to hide away some
>> "insignificant:" tags? reflog might be an option if we have something
>> like foo@{/v2} to quickly retrieve the reflog entry whose message
>> contains "v2".
>
> You can normally find the previous commit via the reflog. Various
> changes to the settings can make the reflog be maintained for longer
> if you have longer lived patch series. That's how I would suggest it,
> rather than branches, as I tend not to keep old versions around on
> separate tags or branches.
>
> The problem with "foo@{/v2}" is that people don't always keep values
> inside the message it self, but maybe "foo@{/pattern}" would be a
> useful extension?

"reflog message" is different from "commit message". I was referring
to the first one (which is out of user control), perhaps you were
referring to the second one? I don't expect people to add v2 to
manually. If we have something like foo@{/v2} then we can teach
send-email (or format-patch) to add a reflog entry with "v2" in it.
But maybe we're abusing reflog..
-- 
Duy

Re: [PATCH v4 01/10] ref-filter: add option to align atoms to the left

[Duy Nguyen]

On Mon, Jul 27, 2015 at 5:18 PM, Duy Nguyen <pclouds@gmail.com> wrote:
> On Mon, Jul 27, 2015 at 2:39 PM, Jacob Keller <jacob.keller@gmail.com> wrote:
>> On Sun, Jul 26, 2015 at 5:39 PM, Duy Nguyen <pclouds@gmail.com> wrote:
>>> On Sun, Jul 26, 2015 at 11:08 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>>>> You can generate an interdiff with "git diff branchname-v4
>>>> branchname-v5", for instance.
>>>
>>> Off topic. But what stops me from doing this often is it creates a big
>>> mess in "git tag -l". Do we have an option to hide away some
>>> "insignificant:" tags? reflog might be an option if we have something
>>> like foo@{/v2} to quickly retrieve the reflog entry whose message
>>> contains "v2".
> ...
>
> But maybe we're abusing reflog..

Actually a good place for this stuff is "git branch
--edit-description". A lot of manual steps to save old refs, do
inter-diff.. but it's probably good enough.
-- 
Duy

[PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Karthik Nayak]

Make color which was considered as an atom, to use
ref_formatting_state and act as a pseudo atom. This allows
interchangeability between 'align' and 'color'.

Helped-by: Junio C Hamano <gitster@pobox.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 ref-filter.c | 16 ++++++++++++----
 ref-filter.h |  1 +
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/ref-filter.c b/ref-filter.c
index 3c90ffc..fd13a23 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -663,7 +663,8 @@ static void populate_value(struct ref_formatting_state *state,
 
 			if (color_parse(name + 6, color) < 0)
 				die(_("unable to parse format"));
-			v->s = xstrdup(color);
+			state->color = xstrdup(color);
+			v->pseudo_atom = 1;
 			continue;
 		} else if (!strcmp(name, "flag")) {
 			char buf[256], *cp = buf;
@@ -1217,6 +1218,11 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
 static void ref_formatting(struct ref_formatting_state *state, struct atom_value *v,
 			   struct strbuf *value)
 {
+	if (state->color) {
+		strbuf_addstr(value, state->color);
+		free((void *)state->color);
+		state->color = NULL;
+	}
 	if (state->pad_to_right) {
 		if (!is_utf8(v->s))
 			strbuf_addf(value, "%-*s", state->pad_to_right, v->s);
@@ -1224,8 +1230,9 @@ static void ref_formatting(struct ref_formatting_state *state, struct atom_value
 			int len = strlen(v->s) - utf8_strwidth(v->s);
 			strbuf_addf(value, "%-*s", state->pad_to_right + len, v->s);
 		}
-	} else
-		strbuf_addf(value, "%s", v->s);
+		return;
+	}
+	strbuf_addf(value, "%s", v->s);
 }
 
 static void print_value(struct ref_formatting_state *state, struct atom_value *v)
@@ -1326,7 +1333,8 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 
 		if (color_parse("reset", color) < 0)
 			die("BUG: couldn't parse 'reset' as a color");
-		resetv.s = color;
+		resetv.s = "";
+		state.color = xstrdup(color);
 		print_value(&state, &resetv);
 	}
 	putchar('\n');
diff --git a/ref-filter.h b/ref-filter.h
index ea2d0e6..bacbb23 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -31,6 +31,7 @@ struct ref_sorting {
 struct ref_formatting_state {
 	unsigned int pad_to_right; /*pad atoms to the right*/
 	int quote_style;
+	const char *color;
 };
 
 struct ref_array_item {
-- 
2.4.6

Re: [PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Junio C Hamano]

Karthik Nayak <karthik.188@gmail.com> writes:

> Make color which was considered as an atom, to use
> ref_formatting_state and act as a pseudo atom. This allows
> interchangeability between 'align' and 'color'.
>
> Helped-by: Junio C Hamano <gitster@pobox.com>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
> ---

I think 1/10 and 2/10 are the other way around.  Preferably, these
would be three patches, in this order:

 (1) prepare the "formatting state" and pass it around; no other
     code change.

 (2) have "color" use that facility.

 (3) add a new feature using that facility.

The first two may want to be combined into a single patch, if it
does not make the patch too noisy.

>  ref-filter.c | 16 ++++++++++++----
>  ref-filter.h |  1 +
>  2 files changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/ref-filter.c b/ref-filter.c
> index 3c90ffc..fd13a23 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -663,7 +663,8 @@ static void populate_value(struct ref_formatting_state *state,
>  
>  			if (color_parse(name + 6, color) < 0)
>  				die(_("unable to parse format"));
> -			v->s = xstrdup(color);
> +			state->color = xstrdup(color);
> +			v->pseudo_atom = 1;
>  			continue;
>  		} else if (!strcmp(name, "flag")) {
>  			char buf[256], *cp = buf;
> @@ -1217,6 +1218,11 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
>  static void ref_formatting(struct ref_formatting_state *state, struct atom_value *v,
>  			   struct strbuf *value)
>  {
> +	if (state->color) {
> +		strbuf_addstr(value, state->color);
> +		free((void *)state->color);
> +		state->color = NULL;
> +	}
>  	if (state->pad_to_right) {
>  		if (!is_utf8(v->s))
>  			strbuf_addf(value, "%-*s", state->pad_to_right, v->s);
> @@ -1224,8 +1230,9 @@ static void ref_formatting(struct ref_formatting_state *state, struct atom_value
>  			int len = strlen(v->s) - utf8_strwidth(v->s);
>  			strbuf_addf(value, "%-*s", state->pad_to_right + len, v->s);
>  		}
> -	} else
> -		strbuf_addf(value, "%s", v->s);
> +		return;
> +	}
> +	strbuf_addf(value, "%s", v->s);
>  }
>  
>  static void print_value(struct ref_formatting_state *state, struct atom_value *v)
> @@ -1326,7 +1333,8 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
>  
>  		if (color_parse("reset", color) < 0)
>  			die("BUG: couldn't parse 'reset' as a color");
> -		resetv.s = color;
> +		resetv.s = "";
> +		state.color = xstrdup(color);
>  		print_value(&state, &resetv);
>  	}
>  	putchar('\n');
> diff --git a/ref-filter.h b/ref-filter.h
> index ea2d0e6..bacbb23 100644
> --- a/ref-filter.h
> +++ b/ref-filter.h
> @@ -31,6 +31,7 @@ struct ref_sorting {
>  struct ref_formatting_state {
>  	unsigned int pad_to_right; /*pad atoms to the right*/
>  	int quote_style;
> +	const char *color;
>  };
>  
>  struct ref_array_item {

Re: [PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Karthik Nayak]

On Sat, Jul 25, 2015 at 3:16 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Karthik Nayak <karthik.188@gmail.com> writes:
>
>> Make color which was considered as an atom, to use
>> ref_formatting_state and act as a pseudo atom. This allows
>> interchangeability between 'align' and 'color'.
>>
>> Helped-by: Junio C Hamano <gitster@pobox.com>
>> Mentored-by: Christian Couder <christian.couder@gmail.com>
>> Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>
> I think 1/10 and 2/10 are the other way around.  Preferably, these
> would be three patches, in this order:
>
>  (1) prepare the "formatting state" and pass it around; no other
>      code change.
>
>  (2) have "color" use that facility.
>
>  (3) add a new feature using that facility.
>
> The first two may want to be combined into a single patch, if it
> does not make the patch too noisy.
>

Ill reverse the patches and merge the first two as you suggested.
Thanks

-- 
Regards,
Karthik Nayak

Re: [PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Eric Sunshine]

On Sat, Jul 25, 2015 at 12:15 AM, Karthik Nayak <karthik.188@gmail.com> wrote:
> On Sat, Jul 25, 2015 at 3:16 AM, Junio C Hamano <gitster@pobox.com> wrote:
>> Karthik Nayak <karthik.188@gmail.com> writes:
>>> Make color which was considered as an atom, to use
>>> ref_formatting_state and act as a pseudo atom. This allows
>>> interchangeability between 'align' and 'color'.
>>>
>>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>>> ---
>> I think 1/10 and 2/10 are the other way around.  Preferably, these
>> would be three patches, in this order:
>>
>>  (1) prepare the "formatting state" and pass it around; no other
>>      code change.
>>
>>  (2) have "color" use that facility.
>>
>>  (3) add a new feature using that facility.
>>
>> The first two may want to be combined into a single patch, if it
>> does not make the patch too noisy.
>
> Ill reverse the patches and merge the first two as you suggested.

While reviewing patch 1/10, it required more effort and was
distracting to have to separate out (mentally) changes which were
specific to the new %(align:X) pseudo-atom and those which introduced
the "formatting state". As such, it probably would be a good idea to
aim for the three distinct patches suggested by Junio rather than
aiming, up front, to merge the first two. After all, they are
conceptually distinct changes, and keeping them separate is friendlier
to reviewers. In the end, you may find that patch 1 is so trivial that
it can be merged with patch 2 without making review more difficult,
however, keeping them distinct during development helps you avoid
conflating unrelated changes.

Re: [PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Eric Sunshine]

On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
> Make color which was considered as an atom, to use
> ref_formatting_state and act as a pseudo atom. This allows
> interchangeability between 'align' and 'color'.
>
> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
> ---
> diff --git a/ref-filter.c b/ref-filter.c
> index 3c90ffc..fd13a23 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -663,7 +663,8 @@ static void populate_value(struct ref_formatting_state *state,
> -                       v->s = xstrdup(color);
> +                       state->color = xstrdup(color);
> +                       v->pseudo_atom = 1;
> @@ -1217,6 +1218,11 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
> +       if (state->color) {
> +               strbuf_addstr(value, state->color);
> +               free((void *)state->color);
> +               state->color = NULL;
> +       }
> @@ -1326,7 +1333,8 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
> -               resetv.s = color;
> +               resetv.s = "";
> +               state.color = xstrdup(color);
> diff --git a/ref-filter.h b/ref-filter.h
> index ea2d0e6..bacbb23 100644
> --- a/ref-filter.h
> +++ b/ref-filter.h
> @@ -31,6 +31,7 @@ struct ref_sorting {
>  struct ref_formatting_state {
>         unsigned int pad_to_right; /*pad atoms to the right*/
>         int quote_style;
> +       const char *color;
>  };

Should 'color' should be declared 'char *' rather than 'const char *'?
It's always assigned via xstrdup(), and if declared 'char *', you
wouldn't have to cast away the 'const' when freeing it.

Re: [PATCH v4 02/10] ref-filter: make the 'color' use ref_formatting_state

[Karthik Nayak]

On Sun, Jul 26, 2015 at 9:42 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
>
> Should 'color' should be declared 'char *' rather than 'const char *'?
> It's always assigned via xstrdup(), and if declared 'char *', you
> wouldn't have to cast away the 'const' when freeing it.
>

yes, will change.

>
> While reviewing patch 1/10, it required more effort and was
> distracting to have to separate out (mentally) changes which were
> specific to the new %(align:X) pseudo-atom and those which introduced
> the "formatting state". As such, it probably would be a good idea to
> aim for the three distinct patches suggested by Junio rather than
> aiming, up front, to merge the first two. After all, they are
> conceptually distinct changes, and keeping them separate is friendlier
> to reviewers. In the end, you may find that patch 1 is so trivial that
> it can be merged with patch 2 without making review more difficult,
> however, keeping them distinct during development helps you avoid
> conflating unrelated changes.
>

Yes! I'm doing that like Junio suggested. Thanks for bringing it up :)

-- 
Regards,
Karthik Nayak

[PATCH v4 03/10] ref-filter: add option to filter only tags

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Add a functions called 'for_each_tag_ref_fullpath()' to refs.{c,h}
which iterates through each tag ref without trimming the path.

Add an option in 'filter_refs()' to use 'for_each_tag_ref_fullpath()'
and filter refs. This type checking is done by adding a
'FILTER_REFS_TAGS' in 'ref-filter.h'

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 ref-filter.c | 2 ++
 ref-filter.h | 1 +
 refs.c       | 5 +++++
 refs.h       | 1 +
 4 files changed, 9 insertions(+)

diff --git a/ref-filter.c b/ref-filter.c
index fd13a23..34e6603 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1157,6 +1157,8 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 		ret = for_each_rawref(ref_filter_handler, &ref_cbdata);
 	else if (type & FILTER_REFS_ALL)
 		ret = for_each_ref(ref_filter_handler, &ref_cbdata);
+	else if (type & FILTER_REFS_TAGS)
+		ret = for_each_tag_ref_fullpath(ref_filter_handler, &ref_cbdata);
 	else if (type)
 		die("filter_refs: invalid type");
 
diff --git a/ref-filter.h b/ref-filter.h
index bacbb23..729dece 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -15,6 +15,7 @@
 
 #define FILTER_REFS_INCLUDE_BROKEN 0x1
 #define FILTER_REFS_ALL 0x2
+#define FILTER_REFS_TAGS 0x4
 
 struct atom_value {
 	const char *s;
diff --git a/refs.c b/refs.c
index ce8cd8d..b679fce 100644
--- a/refs.c
+++ b/refs.c
@@ -2103,6 +2103,11 @@ int for_each_tag_ref(each_ref_fn fn, void *cb_data)
 	return for_each_ref_in("refs/tags/", fn, cb_data);
 }
 
+int for_each_tag_ref_fullpath(each_ref_fn fn, void *cb_data)
+{
+	return do_for_each_ref(&ref_cache, "refs/tags/", fn, 0, 0, cb_data);
+}
+
 int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
 {
 	return for_each_ref_in_submodule(submodule, "refs/tags/", fn, cb_data);
diff --git a/refs.h b/refs.h
index e82fca5..e5d53d3 100644
--- a/refs.h
+++ b/refs.h
@@ -174,6 +174,7 @@ extern int head_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
 extern int for_each_tag_ref(each_ref_fn fn, void *cb_data);
+extern int for_each_tag_ref_fullpath(each_ref_fn fn, void *cb_data);
 extern int for_each_branch_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_remote_ref(each_ref_fn fn, void *cb_data);
 extern int for_each_replace_ref(each_ref_fn fn, void *cb_data);
-- 
2.4.6

[PATCH v4 04/10] ref-filter: support printing N lines from tag annotation

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

In 'tag.c' we can print N lines from the annotation of the tag using
the '-n<num>' option. Copy code from 'tag.c' to 'ref-filter' and
modify 'ref-filter' to support printing of N lines from the annotation
of tags.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 builtin/for-each-ref.c                             |   2 +-
 builtin/tag.c                                      |   4 +
 ref-filter.c                                       |  51 ++++++++-
 ref-filter.h                                       |   9 +-
 ...ter-add-option-to-align-atoms-to-the-left.patch | 124 +++++++++++++++++++++
 5 files changed, 186 insertions(+), 4 deletions(-)
 create mode 100644 v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch

diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index 40f343b..e4a4f8a 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@@ -74,7 +74,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 	if (!maxcount || array.nr < maxcount)
 		maxcount = array.nr;
 	for (i = 0; i < maxcount; i++)
-		show_ref_array_item(array.items[i], format, quote_style);
+		show_ref_array_item(array.items[i], format, quote_style, 0);
 	ref_array_clear(&array);
 	return 0;
 }
diff --git a/builtin/tag.c b/builtin/tag.c
index 071d001..10b11ce 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -185,6 +185,10 @@ static enum contains_result contains(struct commit *candidate,
 	return contains_test(candidate, want);
 }
 
+/*
+ * Currently duplicated in ref-filter, will eventually be removed as
+ * we port tag.c to use ref-filter APIs.
+ */
 static void show_tag_lines(const struct object_id *oid, int lines)
 {
 	int i;
diff --git a/ref-filter.c b/ref-filter.c
index 34e6603..08ecce5 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1307,7 +1307,51 @@ static void emit(const char *cp, const char *ep)
 	}
 }
 
-void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
+/*
+ * If 'lines' is greater than 0, print that many lines from the given
+ * object_id 'oid'.
+ */
+static void show_tag_lines(const struct object_id *oid, int lines)
+{
+	int i;
+	unsigned long size;
+	enum object_type type;
+	char *buf, *sp, *eol;
+	size_t len;
+
+	buf = read_sha1_file(oid->hash, &type, &size);
+	if (!buf)
+		die_errno("unable to read object %s", oid_to_hex(oid));
+	if (type != OBJ_COMMIT && type != OBJ_TAG)
+		goto free_return;
+	if (!size)
+		die("an empty %s object %s?",
+		    typename(type), oid_to_hex(oid));
+
+	/* skip header */
+	sp = strstr(buf, "\n\n");
+	if (!sp)
+		goto free_return;
+
+	/* only take up to "lines" lines, and strip the signature from a tag */
+	if (type == OBJ_TAG)
+		size = parse_signature(buf, size);
+	for (i = 0, sp += 2; i < lines && sp < buf + size; i++) {
+		if (i)
+			printf("\n    ");
+		eol = memchr(sp, '\n', size - (sp - buf));
+		len = eol ? eol - sp : size - (sp - buf);
+		fwrite(sp, len, 1, stdout);
+		if (!eol)
+			break;
+		sp = eol + 1;
+	}
+free_return:
+	free(buf);
+}
+
+void show_ref_array_item(struct ref_array_item *info, const char *format,
+			 int quote_style, unsigned int lines)
 {
 	const char *cp, *sp, *ep;
 	struct ref_formatting_state state;
@@ -1339,6 +1383,11 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 		state.color = xstrdup(color);
 		print_value(&state, &resetv);
 	}
+	if (lines > 0) {
+		struct object_id oid;
+		hashcpy(oid.hash, info->objectname);
+		show_tag_lines(&oid, lines);
+	}
 	putchar('\n');
 }
 
diff --git a/ref-filter.h b/ref-filter.h
index 729dece..1e2ee65 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -62,6 +62,7 @@ struct ref_filter {
 	struct commit *merge_commit;
 
 	unsigned int with_commit_tag_algo : 1;
+	unsigned int lines;
 };
 
 struct ref_filter_cbdata {
@@ -93,8 +94,12 @@ int parse_ref_filter_atom(const char *atom, const char *ep);
 int verify_ref_format(const char *format);
 /*  Sort the given ref_array as per the ref_sorting provided */
 void ref_array_sort(struct ref_sorting *sort, struct ref_array *array);
-/*  Print the ref using the given format and quote_style */
-void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style);
+/*
+ * Print the ref using the given format and quote_style. If 'lines' > 0,
+ * print that many lines of the the given ref.
+ */
+void show_ref_array_item(struct ref_array_item *info, const char *format,
+			 int quote_style, unsigned int lines);
 /*  Callback function for parsing the sort option */
 int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset);
 /*  Default sort option based on refname */
diff --git a/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
new file mode 100644
index 0000000..350acae
--- /dev/null
+++ b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
@@ -0,0 +1,124 @@
+From 3a07ca1f56f74ca54b7f3c30e3dfd9fe2fed1cc3 Mon Sep 17 00:00:00 2001
+From: Karthik Nayak <karthik.188@gmail.com>
+Date: Wed, 10 Jun 2015 17:19:55 +0530
+Subject: [PATCH v3 1/9] ref-filter: add option to align atoms to the left
+
+Add a new atom "align" and support %(align:X) where X is a number.
+This will align the preceeding atom value to the left followed by
+spaces for a total length of X characters. If X is less than the item
+size, the entire atom value is printed.
+
+Helped-by: Duy Nguyen <pclouds@gmail.com>
+Mentored-by: Christian Couder <christian.couder@gmail.com>
+Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
+Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
+---
+ ref-filter.c | 41 +++++++++++++++++++++++++++++++++++++++--
+ ref-filter.h |  1 +
+ 2 files changed, 40 insertions(+), 2 deletions(-)
+
+diff --git a/ref-filter.c b/ref-filter.c
+index 7561727..93f59aa 100644
+--- a/ref-filter.c
++++ b/ref-filter.c
+@@ -10,6 +10,8 @@
+ #include "quote.h"
+ #include "ref-filter.h"
+ #include "revision.h"
++#include "utf8.h"
++#include "git-compat-util.h"
+ 
+ typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
+ 
+@@ -53,6 +55,7 @@ static struct {
+ 	{ "flag" },
+ 	{ "HEAD" },
+ 	{ "color" },
++	{ "align" },
+ };
+ 
+ /*
+@@ -620,7 +623,7 @@ static void populate_value(struct ref_array_item *ref)
+ 		const char *name = used_atom[i];
+ 		struct atom_value *v = &ref->value[i];
+ 		int deref = 0;
+-		const char *refname;
++		const char *refname = NULL;
+ 		const char *formatp;
+ 		struct branch *branch = NULL;
+ 
+@@ -687,6 +690,17 @@ static void populate_value(struct ref_array_item *ref)
+ 			else
+ 				v->s = " ";
+ 			continue;
++		} else if (starts_with(name, "align:")) {
++			const char *valp = NULL;
++
++			skip_prefix(name, "align:", &valp);
++			if (!valp[0])
++				die(_("no value given with 'align:'"));
++			strtoul_ui(valp, 10, &ref->align_value);
++			if (ref->align_value < 1)
++				die(_("value should be greater than zero: align:%u"), ref->align_value);
++			v->s = "";
++			continue;
+ 		} else
+ 			continue;
+ 
+@@ -1254,17 +1268,40 @@ static void emit(const char *cp, const char *ep)
+ 	}
+ }
+ 
++static void assign_formating(struct ref_array_item *ref, int parsed_atom, struct atom_value *v)
++{
++	if (ref->align_value && !starts_with(used_atom[parsed_atom], "align")) {
++		unsigned int len = 0;
++
++		if (*v->s)
++			len = utf8_strwidth(v->s);
++		if (ref->align_value > len) {
++			struct strbuf buf = STRBUF_INIT;
++			if (*v->s)
++				strbuf_addstr(&buf, v->s);
++			if (*v->s && v->s[0] == '\0')
++				free((char *)v->s);
++			strbuf_addchars(&buf, ' ', ref->align_value - len);
++			v->s = strbuf_detach(&buf, NULL);
++		}
++		ref->align_value = 0;
++	}
++}
++
+ void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
+ {
+ 	const char *cp, *sp, *ep;
+ 
+ 	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
+ 		struct atom_value *atomv;
++		int parsed_atom;
+ 
+ 		ep = strchr(sp, ')');
+ 		if (cp < sp)
+ 			emit(cp, sp);
+-		get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
++		parsed_atom = parse_ref_filter_atom(sp + 2, ep);
++		get_ref_atom_value(info, parsed_atom, &atomv);
++		assign_formating(info, parsed_atom, atomv);
+ 		print_value(atomv, quote_style);
+ 	}
+ 	if (*cp) {
+diff --git a/ref-filter.h b/ref-filter.h
+index 6bf27d8..12ffbc5 100644
+--- a/ref-filter.h
++++ b/ref-filter.h
+@@ -30,6 +30,7 @@ struct ref_sorting {
+ struct ref_array_item {
+ 	unsigned char objectname[20];
+ 	int flag;
++	unsigned int align_value;
+ 	const char *symref;
+ 	struct commit *commit;
+ 	struct atom_value *value;
+-- 
+2.4.6
+
-- 
2.4.6

Re: [PATCH v4 04/10] ref-filter: support printing N lines from tag annotation

[Eric Sunshine]

On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
> From: Karthik Nayak <karthik.188@gmail.com>
>
> In 'tag.c' we can print N lines from the annotation of the tag using
> the '-n<num>' option. Copy code from 'tag.c' to 'ref-filter' and
> modify 'ref-filter' to support printing of N lines from the annotation
> of tags.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
> ---
>  builtin/for-each-ref.c                             |   2 +-
>  builtin/tag.c                                      |   4 +
>  ref-filter.c                                       |  51 ++++++++-
>  ref-filter.h                                       |   9 +-
>  ...ter-add-option-to-align-atoms-to-the-left.patch | 124 +++++++++++++++++++++
>  5 files changed, 186 insertions(+), 4 deletions(-)
>  create mode 100644 v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch

Somehow you managed to "git add" and "git commit" your v3 patch 1 file
inside this v4 patch 4/10.

> diff --git a/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
> new file mode 100644
> index 0000000..350acae
> --- /dev/null
> +++ b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
> @@ -0,0 +1,124 @@
> +From 3a07ca1f56f74ca54b7f3c30e3dfd9fe2fed1cc3 Mon Sep 17 00:00:00 2001
> +From: Karthik Nayak <karthik.188@gmail.com>
> +Date: Wed, 10 Jun 2015 17:19:55 +0530
> +Subject: [PATCH v3 1/9] ref-filter: add option to align atoms to the left
> +
> +Add a new atom "align" and support %(align:X) where X is a number.
> +This will align the preceeding atom value to the left followed by
> +spaces for a total length of X characters. If X is less than the item
> +size, the entire atom value is printed.
> +
> +Helped-by: Duy Nguyen <pclouds@gmail.com>
> +Mentored-by: Christian Couder <christian.couder@gmail.com>
> +Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
> +Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
> +---
> + ref-filter.c | 41 +++++++++++++++++++++++++++++++++++++++--
> + ref-filter.h |  1 +
> + 2 files changed, 40 insertions(+), 2 deletions(-)

Re: [PATCH v4 04/10] ref-filter: support printing N lines from tag annotation

[Karthik Nayak]

On Sun, Jul 26, 2015 at 10:16 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> From: Karthik Nayak <karthik.188@gmail.com>
>>
>> In 'tag.c' we can print N lines from the annotation of the tag using
>> the '-n<num>' option. Copy code from 'tag.c' to 'ref-filter' and
>> modify 'ref-filter' to support printing of N lines from the annotation
>> of tags.
>>
>> Mentored-by: Christian Couder <christian.couder@gmail.com>
>> Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>>  builtin/for-each-ref.c                             |   2 +-
>>  builtin/tag.c                                      |   4 +
>>  ref-filter.c                                       |  51 ++++++++-
>>  ref-filter.h                                       |   9 +-
>>  ...ter-add-option-to-align-atoms-to-the-left.patch | 124 +++++++++++++++++++++
>>  5 files changed, 186 insertions(+), 4 deletions(-)
>>  create mode 100644 v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
>
> Somehow you managed to "git add" and "git commit" your v3 patch 1 file
> inside this v4 patch 4/10.

Ya! removed it, thanks.

>
>> diff --git a/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
>> new file mode 100644
>> index 0000000..350acae
>> --- /dev/null
>> +++ b/v3-0001-ref-filter-add-option-to-align-atoms-to-the-left.patch
>> @@ -0,0 +1,124 @@
>> +From 3a07ca1f56f74ca54b7f3c30e3dfd9fe2fed1cc3 Mon Sep 17 00:00:00 2001
>> +From: Karthik Nayak <karthik.188@gmail.com>
>> +Date: Wed, 10 Jun 2015 17:19:55 +0530
>> +Subject: [PATCH v3 1/9] ref-filter: add option to align atoms to the left
>> +
>> +Add a new atom "align" and support %(align:X) where X is a number.
>> +This will align the preceeding atom value to the left followed by
>> +spaces for a total length of X characters. If X is less than the item
>> +size, the entire atom value is printed.
>> +
>> +Helped-by: Duy Nguyen <pclouds@gmail.com>
>> +Mentored-by: Christian Couder <christian.couder@gmail.com>
>> +Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
>> +Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> +---
>> + ref-filter.c | 41 +++++++++++++++++++++++++++++++++++++++--
>> + ref-filter.h |  1 +
>> + 2 files changed, 40 insertions(+), 2 deletions(-)



-- 
Regards,
Karthik Nayak

[PATCH v4 05/10] ref-filter: add support to sort by version

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Add support to sort by version using the "v:refname" and
"version:refname" option. This is achieved by using the 'versioncmp()'
function as the comparing function for qsort.

This option is included to support sorting by versions in `git tag -l`
which will eventaully be ported to use ref-filter APIs.

Add documentation and tests for the same.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 Documentation/git-for-each-ref.txt |  3 +++
 ref-filter.c                       | 26 ++++++++++++++------------
 ref-filter.h                       |  3 ++-
 t/t6302-for-each-ref-filter.sh     | 36 ++++++++++++++++++++++++++++++++++++
 4 files changed, 55 insertions(+), 13 deletions(-)

diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index e49d578..224dc8c 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -145,6 +145,9 @@ For sorting purposes, fields with numeric values sort in numeric
 order (`objectsize`, `authordate`, `committerdate`, `taggerdate`).
 All other fields are used to sort in their byte-value order.
 
+There is also an option to sort by versions, this can be done by using
+the fieldname `version:refname` or in short `v:refname`.
+
 In any case, a field name that refers to a field inapplicable to
 the object referred by the ref does not cause an error.  It
 returns an empty string instead.
diff --git a/ref-filter.c b/ref-filter.c
index 08ecce5..8f2148f 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -12,6 +12,7 @@
 #include "revision.h"
 #include "utf8.h"
 #include "git-compat-util.h"
+#include "version.h"
 
 typedef enum { FIELD_STR, FIELD_ULONG, FIELD_TIME } cmp_type;
 
@@ -1180,19 +1181,17 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
 
 	get_ref_atom_value(&state, a, s->atom, &va);
 	get_ref_atom_value(&state, b, s->atom, &vb);
-	switch (cmp_type) {
-	case FIELD_STR:
+	if (s->version)
+		cmp = versioncmp(va->s, vb->s);
+	else if (cmp_type == FIELD_STR)
 		cmp = strcmp(va->s, vb->s);
-		break;
-	default:
-		if (va->ul < vb->ul)
-			cmp = -1;
-		else if (va->ul == vb->ul)
-			cmp = 0;
-		else
-			cmp = 1;
-		break;
-	}
+	else if (va->ul < vb->ul)
+		cmp = -1;
+	else if (va->ul == vb->ul)
+		cmp = 0;
+	else
+		cmp = 1;
+
 	return (s->reverse) ? -cmp : cmp;
 }
 
@@ -1420,6 +1419,9 @@ int parse_opt_ref_sorting(const struct option *opt, const char *arg, int unset)
 		s->reverse = 1;
 		arg++;
 	}
+	if (skip_prefix(arg, "version:", &arg) ||
+	    skip_prefix(arg, "v:", &arg))
+		s->version = 1;
 	len = strlen(arg);
 	s->atom = parse_ref_filter_atom(arg, arg+len);
 	return 0;
diff --git a/ref-filter.h b/ref-filter.h
index 1e2ee65..a12fe0c 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -26,7 +26,8 @@ struct atom_value {
 struct ref_sorting {
 	struct ref_sorting *next;
 	int atom; /* index into used_atom array (internal) */
-	unsigned reverse : 1;
+	unsigned reverse : 1,
+		version : 1;
 };
 
 struct ref_formatting_state {
diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh
index 505a360..5017032 100755
--- a/t/t6302-for-each-ref-filter.sh
+++ b/t/t6302-for-each-ref-filter.sh
@@ -81,4 +81,40 @@ test_expect_success 'filtering with --contains' '
 	test_cmp expect actual
 '
 
+test_expect_success 'setup for version sort' '
+	test_commit foo1.3 &&
+	test_commit foo1.6 &&
+	test_commit foo1.10
+'
+
+test_expect_success 'version sort' '
+	git tag -l --sort=version:refname | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.3
+	foo1.6
+	foo1.10
+	EOF
+	test_cmp expect actual
+'
+
+test_expect_success 'version sort (shortened)' '
+	git tag -l --sort=v:refname | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.3
+	foo1.6
+	foo1.10
+	EOF
+	test_cmp expect actual
+'
+
+test_expect_success 'reverse version sort' '
+	git tag -l --sort=-version:refname | grep "foo" >actual &&
+	cat >expect <<-\EOF &&
+	foo1.10
+	foo1.6
+	foo1.3
+	EOF
+	test_cmp expect actual
+'
+
 test_done
-- 
2.4.6

Re: [PATCH v4 05/10] ref-filter: add support to sort by version

[Junio C Hamano]

Karthik Nayak <karthik.188@gmail.com> writes:

> @@ -1180,19 +1181,17 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
>  
>  	get_ref_atom_value(&state, a, s->atom, &va);
>  	get_ref_atom_value(&state, b, s->atom, &vb);
> -	switch (cmp_type) {
> -	case FIELD_STR:
> +	if (s->version)
> +		cmp = versioncmp(va->s, vb->s);
> +	else if (cmp_type == FIELD_STR)
>  		cmp = strcmp(va->s, vb->s);
> -		break;
> -	default:
> -		if (va->ul < vb->ul)
> -			cmp = -1;
> -		else if (va->ul == vb->ul)
> -			cmp = 0;
> -		else
> -			cmp = 1;
> -		break;
> -	}
> +	else if (va->ul < vb->ul)
> +		cmp = -1;
> +	else if (va->ul == vb->ul)
> +		cmp = 0;
> +	else
> +		cmp = 1;
> +

So there are generally three kinds of comparison possible:

    - if it is to be compared as versions, do versioncmp
    - if it is to be compared as strings, do strcmp
    - if it is to be compared as numbers, do <=> but because
      we are writing in C, not in Perl, do so as if/else/else

Having understood that, the above is not really easy to read and
extend.  We should structure the above more like this:

	if (s->version)
        	... versioncmp
	else if (... FIELD_STR)
        	... strcmp
	else {
		if (a < b)
                	...
		else if (a == b)
                	...
		else
                	...
        }

so that it would be obvious how this code need to be updated
when we need to add yet another kind of comparison.

Without looking at the callers, s->version looks like a misdesign
that should be updated to use the same cmp_type mechanism?  That
would lead to even more obvious construct that is easy to enhance,
i.e.

	switch (cmp_type) {
        case CMP_VERSION:
        	...
	case CMP_STRING:
        	...
	case CMP_NUMBER:
        	...
        }
        
I dunno.

Other than that (and the structure of that "format-state" stuff we
discussed separately), the series was a pleasant read.

Thanks.

Re: [PATCH v4 05/10] ref-filter: add support to sort by version

[Karthik Nayak]

On Sun, Jul 26, 2015 at 4:10 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Karthik Nayak <karthik.188@gmail.com> writes:
>
>> @@ -1180,19 +1181,17 @@ static int cmp_ref_sorting(struct ref_sorting *s, struct ref_array_item *a, stru
>>
>>       get_ref_atom_value(&state, a, s->atom, &va);
>>       get_ref_atom_value(&state, b, s->atom, &vb);
>> -     switch (cmp_type) {
>> -     case FIELD_STR:
>> +     if (s->version)
>> +             cmp = versioncmp(va->s, vb->s);
>> +     else if (cmp_type == FIELD_STR)
>>               cmp = strcmp(va->s, vb->s);
>> -             break;
>> -     default:
>> -             if (va->ul < vb->ul)
>> -                     cmp = -1;
>> -             else if (va->ul == vb->ul)
>> -                     cmp = 0;
>> -             else
>> -                     cmp = 1;
>> -             break;
>> -     }
>> +     else if (va->ul < vb->ul)
>> +             cmp = -1;
>> +     else if (va->ul == vb->ul)
>> +             cmp = 0;
>> +     else
>> +             cmp = 1;
>> +
>
> So there are generally three kinds of comparison possible:
>
>     - if it is to be compared as versions, do versioncmp
>     - if it is to be compared as strings, do strcmp
>     - if it is to be compared as numbers, do <=> but because
>       we are writing in C, not in Perl, do so as if/else/else
>
> Having understood that, the above is not really easy to read and
> extend.  We should structure the above more like this:
>
>         if (s->version)
>                 ... versioncmp
>         else if (... FIELD_STR)
>                 ... strcmp
>         else {
>                 if (a < b)
>                         ...
>                 else if (a == b)
>                         ...
>                 else
>                         ...
>         }
>
> so that it would be obvious how this code need to be updated
> when we need to add yet another kind of comparison.
>

I find the current version more pleasing to read, The way you've explained
it though, it seems that its better to structure it the way you've
mentioned as this
actually shows the code flow of the three kinds of comparison possible.

> Without looking at the callers, s->version looks like a misdesign
> that should be updated to use the same cmp_type mechanism?  That
> would lead to even more obvious construct that is easy to enhance,
> i.e.
>
>         switch (cmp_type) {
>         case CMP_VERSION:
>                 ...
>         case CMP_STRING:
>                 ...
>         case CMP_NUMBER:
>                 ...
>         }
>
> I dunno.
>
> Other than that (and the structure of that "format-state" stuff we
> discussed separately), the series was a pleasant read.
>
> Thanks.

That was the previous design, but Duy asked me to do this so
that we could support all atoms. And I agree with him on this.

http://article.gmane.org/gmane.comp.version-control.git/273888

-- 
Regards,
Karthik Nayak

Re: [PATCH v4 05/10] ref-filter: add support to sort by version

[Junio C Hamano]

Karthik Nayak <karthik.188@gmail.com> writes:

> On Sun, Jul 26, 2015 at 4:10 AM, Junio C Hamano <gitster@pobox.com> wrote:
>
>> Without looking at the callers, s->version looks like a misdesign
>> that should be updated to use the same cmp_type mechanism?  That
>> would lead to even more obvious construct that is easy to enhance,
>> i.e.
>>
>>         switch (cmp_type) {
>>         case CMP_VERSION:
>>                 ...
>>         case CMP_STRING:
>>                 ...
>>         case CMP_NUMBER:
>>                 ...
>>         }
>>
>> I dunno.
>>
>> Other than that (and the structure of that "format-state" stuff we
>> discussed separately), the series was a pleasant read.
>>
>> Thanks.
>
> That was the previous design, but Duy asked me to do this so
> that we could support all atoms. And I agree with him on this.
>
> http://article.gmane.org/gmane.comp.version-control.git/273888

I am not objecting, but $gmane/273888 does not immediately read, at
least to me, as suggesting using a mechanism different from cmp_type
but a dedicated field s->version.  Puzzled...

Re: [PATCH v4 05/10] ref-filter: add support to sort by version

[Karthik Nayak]

On Mon, Jul 27, 2015 at 8:54 PM, Junio C Hamano <gitster@pobox.com> wrote:
> Karthik Nayak <karthik.188@gmail.com> writes:
>
>> On Sun, Jul 26, 2015 at 4:10 AM, Junio C Hamano <gitster@pobox.com> wrote:
>>
>>> Without looking at the callers, s->version looks like a misdesign
>>> that should be updated to use the same cmp_type mechanism?  That
>>> would lead to even more obvious construct that is easy to enhance,
>>> i.e.
>>>
>>>         switch (cmp_type) {
>>>         case CMP_VERSION:
>>>                 ...
>>>         case CMP_STRING:
>>>                 ...
>>>         case CMP_NUMBER:
>>>                 ...
>>>         }
>>>
>>> I dunno.
>>>
>>> Other than that (and the structure of that "format-state" stuff we
>>> discussed separately), the series was a pleasant read.
>>>
>>> Thanks.
>>
>> That was the previous design, but Duy asked me to do this so
>> that we could support all atoms. And I agree with him on this.
>>
>> http://article.gmane.org/gmane.comp.version-control.git/273888
>
> I am not objecting, but $gmane/273888 does not immediately read, at
> least to me, as suggesting using a mechanism different from cmp_type
> but a dedicated field s->version.  Puzzled...
>

What I mean was since "version"/"v" aren't atoms as such, their processing is
done before we parse through atoms and fill used_atoms and used_atom_type.
cmp_type is obtained from the used_atom_type, which isn't filled by
"version"/"v".
Hence the dedicated field, just like reverse.

-- 
Regards,
Karthik Nayak

[PATCH v4 06/10] ref-filter: add option to match literal pattern

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Since 'ref-filter' only has an option to match path names add an
option for plain fnmatch pattern-matching.

This is to support the pattern matching options which are used in `git
tag -l` and `git branch -l` where we can match patterns like `git tag
-l foo*` which would match all tags which has a "foo*" pattern.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 builtin/for-each-ref.c |  1 +
 ref-filter.c           | 37 ++++++++++++++++++++++++++++++++++++-
 ref-filter.h           |  3 ++-
 3 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index e4a4f8a..3ad6a64 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@@ -68,6 +68,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 	git_config(git_default_config, NULL);
 
 	filter.name_patterns = argv;
+	filter.match_as_path = 1;
 	filter_refs(&array, &filter, FILTER_REFS_ALL | FILTER_REFS_INCLUDE_BROKEN);
 	ref_array_sort(sorting, &array);
 
diff --git a/ref-filter.c b/ref-filter.c
index 8f2148f..0a64b84 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -951,6 +951,31 @@ static int commit_contains(struct ref_filter *filter, struct commit *commit)
 
 /*
  * Return 1 if the refname matches one of the patterns, otherwise 0.
+ * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
+ * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
+ * matches "refs/heads/mas*", too).
+ */
+static int match_pattern(const char **patterns, const char *refname)
+{
+	for (; *patterns; patterns++) {
+		/*
+		 * When no '--format' option is given we need to skip the prefix
+		 * for matching refs of tags and branches.
+		 */
+		if (!starts_with(*patterns, "refs/tags/"))
+			skip_prefix(refname, "refs/tags/", &refname);
+		if (!starts_with(*patterns, "refs/heads/"))
+			skip_prefix(refname, "refs/heads/", &refname);
+		if (!starts_with(*patterns, "refs/remotes/"))
+			skip_prefix(refname, "refs/remotes/", &refname);
+		if (!wildmatch(*patterns, refname, 0, NULL))
+			return 1;
+	}
+	return 0;
+}
+
+/*
+ * Return 1 if the refname matches one of the patterns, otherwise 0.
  * A pattern can be path prefix (e.g. a refname "refs/heads/master"
  * matches a pattern "refs/heads/") or a wildcard (e.g. the same ref
  * matches "refs/heads/m*",too).
@@ -974,6 +999,16 @@ static int match_name_as_path(const char **pattern, const char *refname)
 	return 0;
 }
 
+/* Return 1 if the refname matches one of the patterns, otherwise 0. */
+static int filter_pattern_match(struct ref_filter *filter, const char *refname)
+{
+	if (!*filter->name_patterns)
+		return 1; /* No pattern always matches */
+	if (filter->match_as_path)
+		return match_name_as_path(filter->name_patterns, refname);
+	return match_pattern(filter->name_patterns, refname);
+}
+
 /*
  * Given a ref (sha1, refname), check if the ref belongs to the array
  * of sha1s. If the given ref is a tag, check if the given tag points
@@ -1042,7 +1077,7 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 		return 0;
 	}
 
-	if (*filter->name_patterns && !match_name_as_path(filter->name_patterns, refname))
+	if (!filter_pattern_match(filter, refname))
 		return 0;
 
 	if (filter->points_at.nr && !match_points_at(&filter->points_at, oid->hash, refname))
diff --git a/ref-filter.h b/ref-filter.h
index a12fe0c..f1933e0 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -62,7 +62,8 @@ struct ref_filter {
 	} merge;
 	struct commit *merge_commit;
 
-	unsigned int with_commit_tag_algo : 1;
+	unsigned int with_commit_tag_algo : 1,
+		match_as_path : 1;
 	unsigned int lines;
 };
 
-- 
2.4.6

Re: [PATCH v4 06/10] ref-filter: add option to match literal pattern

[Eric Sunshine]

On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
> Since 'ref-filter' only has an option to match path names add an
> option for plain fnmatch pattern-matching.
>
> This is to support the pattern matching options which are used in `git
> tag -l` and `git branch -l` where we can match patterns like `git tag
> -l foo*` which would match all tags which has a "foo*" pattern.
>
> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
> ---
> diff --git a/ref-filter.c b/ref-filter.c
> index 8f2148f..0a64b84 100644
> --- a/ref-filter.c
> +++ b/ref-filter.c
> @@ -951,6 +951,31 @@ static int commit_contains(struct ref_filter *filter, struct commit *commit)
>
>  /*
>   * Return 1 if the refname matches one of the patterns, otherwise 0.
> + * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
> + * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
> + * matches "refs/heads/mas*", too).
> + */
> +static int match_pattern(const char **patterns, const char *refname)
> +{
> +       for (; *patterns; patterns++) {
> +               /*
> +                * When no '--format' option is given we need to skip the prefix
> +                * for matching refs of tags and branches.
> +                */
> +               if (!starts_with(*patterns, "refs/tags/"))
> +                       skip_prefix(refname, "refs/tags/", &refname);
> +               if (!starts_with(*patterns, "refs/heads/"))
> +                       skip_prefix(refname, "refs/heads/", &refname);
> +               if (!starts_with(*patterns, "refs/remotes/"))
> +                       skip_prefix(refname, "refs/remotes/", &refname);

Note the inefficiency here: You're performing an "expensive"
starts_with() on each pattern for each refname even though the
patterns will never change. You could instead compute starts_with()
for each pattern just once, in a preprocessing step, and remember each
result as a boolean, and then use the computed booleans here in place
of starts_with(). For a few refnames, this may not make a difference,
but for a project with a huge number, it could. Whether such an
optimization is worth the complexity (at this time or ever) is
something that can be answered by taking measurements.

Also, the repetition in the code is not all that pretty. You could
instead place "refs/tags/", "refs/heads/", and "refs/remotes/" in a
table and then loop over them rather than repeating the code for each
one, though whether that would be an improvement is likely a judgment
call (so not something I'd insist upon).

> +               if (!wildmatch(*patterns, refname, 0, NULL))
> +                       return 1;
> +       }
> +       return 0;
> +}

Re: [PATCH v4 06/10] ref-filter: add option to match literal pattern

[Karthik Nayak]

On Sun, Jul 26, 2015 at 10:45 AM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> On Fri, Jul 24, 2015 at 3:04 PM, Karthik Nayak <karthik.188@gmail.com> wrote:
>> Since 'ref-filter' only has an option to match path names add an
>> option for plain fnmatch pattern-matching.
>>
>> This is to support the pattern matching options which are used in `git
>> tag -l` and `git branch -l` where we can match patterns like `git tag
>> -l foo*` which would match all tags which has a "foo*" pattern.
>>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>> diff --git a/ref-filter.c b/ref-filter.c
>> index 8f2148f..0a64b84 100644
>> --- a/ref-filter.c
>> +++ b/ref-filter.c
>> @@ -951,6 +951,31 @@ static int commit_contains(struct ref_filter *filter, struct commit *commit)
>>
>>  /*
>>   * Return 1 if the refname matches one of the patterns, otherwise 0.
>> + * A pattern can be a literal prefix (e.g. a refname "refs/heads/master"
>> + * matches a pattern "refs/heads/mas") or a wildcard (e.g. the same ref
>> + * matches "refs/heads/mas*", too).
>> + */
>> +static int match_pattern(const char **patterns, const char *refname)
>> +{
>> +       for (; *patterns; patterns++) {
>> +               /*
>> +                * When no '--format' option is given we need to skip the prefix
>> +                * for matching refs of tags and branches.
>> +                */
>> +               if (!starts_with(*patterns, "refs/tags/"))
>> +                       skip_prefix(refname, "refs/tags/", &refname);
>> +               if (!starts_with(*patterns, "refs/heads/"))
>> +                       skip_prefix(refname, "refs/heads/", &refname);
>> +               if (!starts_with(*patterns, "refs/remotes/"))
>> +                       skip_prefix(refname, "refs/remotes/", &refname);
>
> Note the inefficiency here: You're performing an "expensive"
> starts_with() on each pattern for each refname even though the
> patterns will never change. You could instead compute starts_with()
> for each pattern just once, in a preprocessing step, and remember each
> result as a boolean, and then use the computed booleans here in place
> of starts_with(). For a few refnames, this may not make a difference,
> but for a project with a huge number, it could. Whether such an
> optimization is worth the complexity (at this time or ever) is
> something that can be answered by taking measurements.
>
> Also, the repetition in the code is not all that pretty. You could
> instead place "refs/tags/", "refs/heads/", and "refs/remotes/" in a
> table and then loop over them rather than repeating the code for each
> one, though whether that would be an improvement is likely a judgment
> call (so not something I'd insist upon).
>

I just put the "starts_with()" code so as to ensure that its only used when
we don't say "refs/heads/", "refs/remotes/" or "refs/tags/" in the pattern.
But looking at the tag.c and branch.c implementations this should always be
done. Hence I think Ill move it outside the loop and make it mandatory as this
pattern matching is only used by tag and branch and as they by default
remove the
path of the ref. I think it'd make sense to remove it here also.

-- 
Regards,
Karthik Nayak

[PATCH v4 07/10] tag.c: use 'ref-filter' data structures

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Make 'tag.c' use 'ref-filter' data structures and make changes to
support the new data structures. This is a part of the process
of porting 'tag.c' to use 'ref-filter' APIs.

This is a temporary step before porting 'tag.c' to use 'ref-filter'
completely. As this is a temporary step, most of the code
introduced here will be removed when 'tag.c' is ported over to use
'ref-filter' APIs

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 builtin/tag.c | 106 +++++++++++++++++++++++++++++++---------------------------
 1 file changed, 57 insertions(+), 49 deletions(-)

diff --git a/builtin/tag.c b/builtin/tag.c
index 10b11ce..dadc686 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -17,6 +17,7 @@
 #include "gpg-interface.h"
 #include "sha1-array.h"
 #include "column.h"
+#include "ref-filter.h"
 
 static const char * const git_tag_usage[] = {
 	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
@@ -34,15 +35,6 @@ static const char * const git_tag_usage[] = {
 
 static int tag_sort;
 
-struct tag_filter {
-	const char **patterns;
-	int lines;
-	int sort;
-	struct string_list tags;
-	struct commit_list *with_commit;
-};
-
-static struct sha1_array points_at;
 static unsigned int colopts;
 
 static int match_pattern(const char **patterns, const char *ref)
@@ -61,19 +53,20 @@ static int match_pattern(const char **patterns, const char *ref)
  * removed as we port tag.c to use the ref-filter APIs.
  */
 static const unsigned char *match_points_at(const char *refname,
-					    const unsigned char *sha1)
+					    const unsigned char *sha1,
+					    struct sha1_array *points_at)
 {
 	const unsigned char *tagged_sha1 = NULL;
 	struct object *obj;
 
-	if (sha1_array_lookup(&points_at, sha1) >= 0)
+	if (sha1_array_lookup(points_at, sha1) >= 0)
 		return sha1;
 	obj = parse_object(sha1);
 	if (!obj)
 		die(_("malformed object at '%s'"), refname);
 	if (obj->type == OBJ_TAG)
 		tagged_sha1 = ((struct tag *)obj)->tagged->sha1;
-	if (tagged_sha1 && sha1_array_lookup(&points_at, tagged_sha1) >= 0)
+	if (tagged_sha1 && sha1_array_lookup(points_at, tagged_sha1) >= 0)
 		return tagged_sha1;
 	return NULL;
 }
@@ -228,12 +221,24 @@ free_return:
 	free(buf);
 }
 
+static void ref_array_append(struct ref_array *array, const char *refname)
+{
+	size_t len = strlen(refname);
+	struct ref_array_item *ref = xcalloc(1, sizeof(struct ref_array_item) + len + 1);
+	memcpy(ref->refname, refname, len);
+	ref->refname[len] = '\0';
+	REALLOC_ARRAY(array->items, array->nr + 1);
+	array->items[array->nr++] = ref;
+}
+
 static int show_reference(const char *refname, const struct object_id *oid,
 			  int flag, void *cb_data)
 {
-	struct tag_filter *filter = cb_data;
+	struct ref_filter_cbdata *data = cb_data;
+	struct ref_array *array = data->array;
+	struct ref_filter *filter = data->filter;
 
-	if (match_pattern(filter->patterns, refname)) {
+	if (match_pattern(filter->name_patterns, refname)) {
 		if (filter->with_commit) {
 			struct commit *commit;
 
@@ -244,12 +249,12 @@ static int show_reference(const char *refname, const struct object_id *oid,
 				return 0;
 		}
 
-		if (points_at.nr && !match_points_at(refname, oid->hash))
+		if (filter->points_at.nr && !match_points_at(refname, oid->hash, &filter->points_at))
 			return 0;
 
 		if (!filter->lines) {
-			if (filter->sort)
-				string_list_append(&filter->tags, refname);
+			if (tag_sort)
+				ref_array_append(array, refname);
 			else
 				printf("%s\n", refname);
 			return 0;
@@ -264,36 +269,36 @@ static int show_reference(const char *refname, const struct object_id *oid,
 
 static int sort_by_version(const void *a_, const void *b_)
 {
-	const struct string_list_item *a = a_;
-	const struct string_list_item *b = b_;
-	return versioncmp(a->string, b->string);
+	const struct ref_array_item *a = *((struct ref_array_item **)a_);
+	const struct ref_array_item *b = *((struct ref_array_item **)b_);
+	return versioncmp(a->refname, b->refname);
 }
 
-static int list_tags(const char **patterns, int lines,
-		     struct commit_list *with_commit, int sort)
+static int list_tags(struct ref_filter *filter, int sort)
 {
-	struct tag_filter filter;
+	struct ref_array array;
+	struct ref_filter_cbdata data;
+
+	memset(&array, 0, sizeof(array));
+	data.array = &array;
+	data.filter = filter;
 
-	filter.patterns = patterns;
-	filter.lines = lines;
-	filter.sort = sort;
-	filter.with_commit = with_commit;
-	memset(&filter.tags, 0, sizeof(filter.tags));
-	filter.tags.strdup_strings = 1;
+	if (filter->lines == -1)
+		filter->lines = 0;
 
-	for_each_tag_ref(show_reference, (void *)&filter);
+	for_each_tag_ref(show_reference, &data);
 	if (sort) {
 		int i;
 		if ((sort & SORT_MASK) == VERCMP_SORT)
-			qsort(filter.tags.items, filter.tags.nr,
-			      sizeof(struct string_list_item), sort_by_version);
+			qsort(array.items, array.nr,
+			      sizeof(struct ref_array_item *), sort_by_version);
 		if (sort & REVERSE_SORT)
-			for (i = filter.tags.nr - 1; i >= 0; i--)
-				printf("%s\n", filter.tags.items[i].string);
+			for (i = array.nr - 1; i >= 0; i--)
+				printf("%s\n", array.items[i]->refname);
 		else
-			for (i = 0; i < filter.tags.nr; i++)
-				printf("%s\n", filter.tags.items[i].string);
-		string_list_clear(&filter.tags, 0);
+			for (i = 0; i < array.nr; i++)
+				printf("%s\n", array.items[i]->refname);
+		ref_array_clear(&array);
 	}
 	return 0;
 }
@@ -574,16 +579,16 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	const char *object_ref, *tag;
 	struct create_tag_options opt;
 	char *cleanup_arg = NULL;
-	int annotate = 0, force = 0, lines = -1;
+	int annotate = 0, force = 0;
 	int cmdmode = 0;
 	const char *msgfile = NULL, *keyid = NULL;
 	struct msg_arg msg = { 0, STRBUF_INIT };
-	struct commit_list *with_commit = NULL;
 	struct ref_transaction *transaction;
 	struct strbuf err = STRBUF_INIT;
+	struct ref_filter filter;
 	struct option options[] = {
 		OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
-		{ OPTION_INTEGER, 'n', NULL, &lines, N_("n"),
+		{ OPTION_INTEGER, 'n', NULL, &filter.lines, N_("n"),
 				N_("print <n> lines of each tag message"),
 				PARSE_OPT_OPTARG, NULL, 1 },
 		OPT_CMDMODE('d', "delete", &cmdmode, N_("delete tags"), 'd'),
@@ -604,14 +609,14 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 
 		OPT_GROUP(N_("Tag listing options")),
 		OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
-		OPT_CONTAINS(&with_commit, N_("print only tags that contain the commit")),
-		OPT_WITH(&with_commit, N_("print only tags that contain the commit")),
+		OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
 		{
 			OPTION_CALLBACK, 0, "sort", &tag_sort, N_("type"), N_("sort tags"),
 			PARSE_OPT_NONEG, parse_opt_sort
 		},
 		{
-			OPTION_CALLBACK, 0, "points-at", &points_at, N_("object"),
+			OPTION_CALLBACK, 0, "points-at", &filter.points_at, N_("object"),
 			N_("print only tags of the object"), 0, parse_opt_object_name
 		},
 		OPT_END()
@@ -620,6 +625,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	git_config(git_tag_config, NULL);
 
 	memset(&opt, 0, sizeof(opt));
+	memset(&filter, 0, sizeof(filter));
+	filter.lines = -1;
 
 	argc = parse_options(argc, argv, prefix, options, git_tag_usage, 0);
 
@@ -636,7 +643,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		usage_with_options(git_tag_usage, options);
 
 	finalize_colopts(&colopts, -1);
-	if (cmdmode == 'l' && lines != -1) {
+	if (cmdmode == 'l' && filter.lines != -1) {
 		if (explicitly_enable_column(colopts))
 			die(_("--column and -n are incompatible"));
 		colopts = 0;
@@ -649,18 +656,19 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			copts.padding = 2;
 			run_column_filter(colopts, &copts);
 		}
-		if (lines != -1 && tag_sort)
+		if (filter.lines != -1 && tag_sort)
 			die(_("--sort and -n are incompatible"));
-		ret = list_tags(argv, lines == -1 ? 0 : lines, with_commit, tag_sort);
+		filter.name_patterns = argv;
+		ret = list_tags(&filter, tag_sort);
 		if (column_active(colopts))
 			stop_column_filter();
 		return ret;
 	}
-	if (lines != -1)
+	if (filter.lines != -1)
 		die(_("-n option is only allowed with -l."));
-	if (with_commit)
+	if (filter.with_commit)
 		die(_("--contains option is only allowed with -l."));
-	if (points_at.nr)
+	if (filter.points_at.nr)
 		die(_("--points-at option is only allowed with -l."));
 	if (cmdmode == 'd')
 		return for_each_tag_name(argv, delete_tag);
-- 
2.4.6

[PATCH v4 08/10] tag.c: use 'ref-filter' APIs

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Make 'tag.c' use 'ref-filter' APIs for iterating through refs sorting
and printing of refs. This removes most of the code used in 'tag.c'
replacing it with calls to the 'ref-filter' library.

Make 'tag.c' use the 'filter_refs()' function provided by 'ref-filter'
to filter out tags based on the options set.

For printing tags we use 'show_ref_array_item()' function provided by
'ref-filter'.

We improve the sorting option provided by 'tag.c' by using the sorting
options provided by 'ref-filter'. This causes the test 'invalid sort
parameter on command line' in t7004 to fail, as 'ref-filter' throws an
error for all sorting fields which are incorrect. The test is changed
to reflect the same.

Modify documentation for the same.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 Documentation/git-tag.txt |  16 ++-
 builtin/tag.c             | 342 ++++++----------------------------------------
 t/t7004-tag.sh            |   8 +-
 3 files changed, 50 insertions(+), 316 deletions(-)

diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index 4b04c2b..02fb363 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -13,7 +13,7 @@ SYNOPSIS
 	<tagname> [<commit> | <object>]
 'git tag' -d <tagname>...
 'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
-	[--column[=<options>] | --no-column] [<pattern>...]
+	[--column[=<options>] | --no-column] [--sort=<key>] [<pattern>...]
 'git tag' -v <tagname>...
 
 DESCRIPTION
@@ -94,14 +94,16 @@ OPTIONS
 	using fnmatch(3)).  Multiple patterns may be given; if any of
 	them matches, the tag is shown.
 
---sort=<type>::
-	Sort in a specific order. Supported type is "refname"
-	(lexicographic order), "version:refname" or "v:refname" (tag
+--sort=<key>::
+	Sort based on the key given.  Prefix `-` to sort in
+	descending order of the value. You may use the --sort=<key> option
+	multiple times, in which case the last key becomes the primary
+	key. Also supports "version:refname" or "v:refname" (tag
 	names are treated as versions). The "version:refname" sort
 	order can also be affected by the
-	"versionsort.prereleaseSuffix" configuration variable. Prepend
-	"-" to reverse sort order. When this option is not given, the
-	sort order defaults to the value configured for the 'tag.sort'
+	"versionsort.prereleaseSuffix" configuration variable.
+	The keys supported are the same as those in `git for-each-ref`.
+	Sort order defaults to the value configured for the 'tag.sort'
 	variable if it exists, or lexicographic order otherwise. See
 	linkgit:git-config[1].
 
diff --git a/builtin/tag.c b/builtin/tag.c
index dadc686..d396872 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -28,278 +28,32 @@ static const char * const git_tag_usage[] = {
 	NULL
 };
 
-#define STRCMP_SORT     0	/* must be zero */
-#define VERCMP_SORT     1
-#define SORT_MASK       0x7fff
-#define REVERSE_SORT    0x8000
-
-static int tag_sort;
-
 static unsigned int colopts;
 
-static int match_pattern(const char **patterns, const char *ref)
-{
-	/* no pattern means match everything */
-	if (!*patterns)
-		return 1;
-	for (; *patterns; patterns++)
-		if (!wildmatch(*patterns, ref, 0, NULL))
-			return 1;
-	return 0;
-}
-
-/*
- * This is currently duplicated in ref-filter.c, and will eventually be
- * removed as we port tag.c to use the ref-filter APIs.
- */
-static const unsigned char *match_points_at(const char *refname,
-					    const unsigned char *sha1,
-					    struct sha1_array *points_at)
-{
-	const unsigned char *tagged_sha1 = NULL;
-	struct object *obj;
-
-	if (sha1_array_lookup(points_at, sha1) >= 0)
-		return sha1;
-	obj = parse_object(sha1);
-	if (!obj)
-		die(_("malformed object at '%s'"), refname);
-	if (obj->type == OBJ_TAG)
-		tagged_sha1 = ((struct tag *)obj)->tagged->sha1;
-	if (tagged_sha1 && sha1_array_lookup(points_at, tagged_sha1) >= 0)
-		return tagged_sha1;
-	return NULL;
-}
-
-static int in_commit_list(const struct commit_list *want, struct commit *c)
-{
-	for (; want; want = want->next)
-		if (!hashcmp(want->item->object.sha1, c->object.sha1))
-			return 1;
-	return 0;
-}
-
-/*
- * The entire code segment for supporting the --contains option has been
- * copied over to ref-filter.{c,h}. This will be deleted evetually when
- * we port tag.c to use ref-filter APIs.
- */
-enum contains_result {
-	CONTAINS_UNKNOWN = -1,
-	CONTAINS_NO = 0,
-	CONTAINS_YES = 1
-};
-
-/*
- * Test whether the candidate or one of its parents is contained in the list.
- * Do not recurse to find out, though, but return -1 if inconclusive.
- */
-static enum contains_result contains_test(struct commit *candidate,
-			    const struct commit_list *want)
-{
-	/* was it previously marked as containing a want commit? */
-	if (candidate->object.flags & TMP_MARK)
-		return 1;
-	/* or marked as not possibly containing a want commit? */
-	if (candidate->object.flags & UNINTERESTING)
-		return 0;
-	/* or are we it? */
-	if (in_commit_list(want, candidate)) {
-		candidate->object.flags |= TMP_MARK;
-		return 1;
-	}
-
-	if (parse_commit(candidate) < 0)
-		return 0;
-
-	return -1;
-}
-
-/*
- * Mimicking the real stack, this stack lives on the heap, avoiding stack
- * overflows.
- *
- * At each recursion step, the stack items points to the commits whose
- * ancestors are to be inspected.
- */
-struct stack {
-	int nr, alloc;
-	struct stack_entry {
-		struct commit *commit;
-		struct commit_list *parents;
-	} *stack;
-};
-
-static void push_to_stack(struct commit *candidate, struct stack *stack)
-{
-	int index = stack->nr++;
-	ALLOC_GROW(stack->stack, stack->nr, stack->alloc);
-	stack->stack[index].commit = candidate;
-	stack->stack[index].parents = candidate->parents;
-}
-
-static enum contains_result contains(struct commit *candidate,
-		const struct commit_list *want)
-{
-	struct stack stack = { 0, 0, NULL };
-	int result = contains_test(candidate, want);
-
-	if (result != CONTAINS_UNKNOWN)
-		return result;
-
-	push_to_stack(candidate, &stack);
-	while (stack.nr) {
-		struct stack_entry *entry = &stack.stack[stack.nr - 1];
-		struct commit *commit = entry->commit;
-		struct commit_list *parents = entry->parents;
-
-		if (!parents) {
-			commit->object.flags |= UNINTERESTING;
-			stack.nr--;
-		}
-		/*
-		 * If we just popped the stack, parents->item has been marked,
-		 * therefore contains_test will return a meaningful 0 or 1.
-		 */
-		else switch (contains_test(parents->item, want)) {
-		case CONTAINS_YES:
-			commit->object.flags |= TMP_MARK;
-			stack.nr--;
-			break;
-		case CONTAINS_NO:
-			entry->parents = parents->next;
-			break;
-		case CONTAINS_UNKNOWN:
-			push_to_stack(parents->item, &stack);
-			break;
-		}
-	}
-	free(stack.stack);
-	return contains_test(candidate, want);
-}
-
-/*
- * Currently duplicated in ref-filter, will eventually be removed as
- * we port tag.c to use ref-filter APIs.
- */
-static void show_tag_lines(const struct object_id *oid, int lines)
-{
-	int i;
-	unsigned long size;
-	enum object_type type;
-	char *buf, *sp, *eol;
-	size_t len;
-
-	buf = read_sha1_file(oid->hash, &type, &size);
-	if (!buf)
-		die_errno("unable to read object %s", oid_to_hex(oid));
-	if (type != OBJ_COMMIT && type != OBJ_TAG)
-		goto free_return;
-	if (!size)
-		die("an empty %s object %s?",
-		    typename(type), oid_to_hex(oid));
-
-	/* skip header */
-	sp = strstr(buf, "\n\n");
-	if (!sp)
-		goto free_return;
-
-	/* only take up to "lines" lines, and strip the signature from a tag */
-	if (type == OBJ_TAG)
-		size = parse_signature(buf, size);
-	for (i = 0, sp += 2; i < lines && sp < buf + size; i++) {
-		if (i)
-			printf("\n    ");
-		eol = memchr(sp, '\n', size - (sp - buf));
-		len = eol ? eol - sp : size - (sp - buf);
-		fwrite(sp, len, 1, stdout);
-		if (!eol)
-			break;
-		sp = eol + 1;
-	}
-free_return:
-	free(buf);
-}
-
-static void ref_array_append(struct ref_array *array, const char *refname)
-{
-	size_t len = strlen(refname);
-	struct ref_array_item *ref = xcalloc(1, sizeof(struct ref_array_item) + len + 1);
-	memcpy(ref->refname, refname, len);
-	ref->refname[len] = '\0';
-	REALLOC_ARRAY(array->items, array->nr + 1);
-	array->items[array->nr++] = ref;
-}
-
-static int show_reference(const char *refname, const struct object_id *oid,
-			  int flag, void *cb_data)
-{
-	struct ref_filter_cbdata *data = cb_data;
-	struct ref_array *array = data->array;
-	struct ref_filter *filter = data->filter;
-
-	if (match_pattern(filter->name_patterns, refname)) {
-		if (filter->with_commit) {
-			struct commit *commit;
-
-			commit = lookup_commit_reference_gently(oid->hash, 1);
-			if (!commit)
-				return 0;
-			if (!contains(commit, filter->with_commit))
-				return 0;
-		}
-
-		if (filter->points_at.nr && !match_points_at(refname, oid->hash, &filter->points_at))
-			return 0;
-
-		if (!filter->lines) {
-			if (tag_sort)
-				ref_array_append(array, refname);
-			else
-				printf("%s\n", refname);
-			return 0;
-		}
-		printf("%-15s ", refname);
-		show_tag_lines(oid, filter->lines);
-		putchar('\n');
-	}
-
-	return 0;
-}
-
-static int sort_by_version(const void *a_, const void *b_)
-{
-	const struct ref_array_item *a = *((struct ref_array_item **)a_);
-	const struct ref_array_item *b = *((struct ref_array_item **)b_);
-	return versioncmp(a->refname, b->refname);
-}
-
-static int list_tags(struct ref_filter *filter, int sort)
+static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting)
 {
 	struct ref_array array;
-	struct ref_filter_cbdata data;
+	char *format;
+	int i;
 
 	memset(&array, 0, sizeof(array));
-	data.array = &array;
-	data.filter = filter;
 
 	if (filter->lines == -1)
 		filter->lines = 0;
 
-	for_each_tag_ref(show_reference, &data);
-	if (sort) {
-		int i;
-		if ((sort & SORT_MASK) == VERCMP_SORT)
-			qsort(array.items, array.nr,
-			      sizeof(struct ref_array_item *), sort_by_version);
-		if (sort & REVERSE_SORT)
-			for (i = array.nr - 1; i >= 0; i--)
-				printf("%s\n", array.items[i]->refname);
-		else
-			for (i = 0; i < array.nr; i++)
-				printf("%s\n", array.items[i]->refname);
-		ref_array_clear(&array);
-	}
+	if (filter->lines)
+		format = "%(align:16)%(refname:short)";
+	else
+		format = "%(refname:short)";
+
+	verify_ref_format(format);
+	filter_refs(&array, filter, FILTER_REFS_TAGS);
+	ref_array_sort(sorting, &array);
+
+	for (i = 0; i < array.nr; i++)
+		show_ref_array_item(array.items[i], format, QUOTE_NONE, filter->lines);
+	ref_array_clear(&array);
+
 	return 0;
 }
 
@@ -366,35 +120,26 @@ static const char tag_template_nocleanup[] =
 	"Lines starting with '%c' will be kept; you may remove them"
 	" yourself if you want to.\n");
 
-/*
- * Parse a sort string, and return 0 if parsed successfully. Will return
- * non-zero when the sort string does not parse into a known type. If var is
- * given, the error message becomes a warning and includes information about
- * the configuration value.
- */
-static int parse_sort_string(const char *var, const char *arg, int *sort)
+/* Parse arg given and add it the ref_sorting array */
+static int parse_sorting_string(const char *arg, struct ref_sorting **sorting_tail)
 {
-	int type = 0, flags = 0;
-
-	if (skip_prefix(arg, "-", &arg))
-		flags |= REVERSE_SORT;
+	struct ref_sorting *s;
+	int len;
 
-	if (skip_prefix(arg, "version:", &arg) || skip_prefix(arg, "v:", &arg))
-		type = VERCMP_SORT;
-	else
-		type = STRCMP_SORT;
+	s = xcalloc(1, sizeof(*s));
+	s->next = *sorting_tail;
+	*sorting_tail = s;
 
-	if (strcmp(arg, "refname")) {
-		if (!var)
-			return error(_("unsupported sort specification '%s'"), arg);
-		else {
-			warning(_("unsupported sort specification '%s' in variable '%s'"),
-				var, arg);
-			return -1;
-		}
+	if (*arg == '-') {
+		s->reverse = 1;
+		arg++;
 	}
+	if (skip_prefix(arg, "version:", &arg) ||
+	    skip_prefix(arg, "v:", &arg))
+		s->version = 1;
 
-	*sort = (type | flags);
+	len = strlen(arg);
+	s->atom = parse_ref_filter_atom(arg, arg+len);
 
 	return 0;
 }
@@ -402,11 +147,12 @@ static int parse_sort_string(const char *var, const char *arg, int *sort)
 static int git_tag_config(const char *var, const char *value, void *cb)
 {
 	int status;
+	struct ref_sorting **sorting_tail = (struct ref_sorting **)cb;
 
 	if (!strcmp(var, "tag.sort")) {
 		if (!value)
 			return config_error_nonbool(var);
-		parse_sort_string(var, value, &tag_sort);
+		parse_sorting_string(value, sorting_tail);
 		return 0;
 	}
 
@@ -564,13 +310,6 @@ static int strbuf_check_tag_ref(struct strbuf *sb, const char *name)
 	return check_refname_format(sb->buf, 0);
 }
 
-static int parse_opt_sort(const struct option *opt, const char *arg, int unset)
-{
-	int *sort = opt->value;
-
-	return parse_sort_string(NULL, arg, sort);
-}
-
 int cmd_tag(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf buf = STRBUF_INIT;
@@ -586,6 +325,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	struct ref_transaction *transaction;
 	struct strbuf err = STRBUF_INIT;
 	struct ref_filter filter;
+	static struct ref_sorting *sorting = NULL, **sorting_tail = &sorting;
 	struct option options[] = {
 		OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
 		{ OPTION_INTEGER, 'n', NULL, &filter.lines, N_("n"),
@@ -611,10 +351,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
 		OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
 		OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
-		{
-			OPTION_CALLBACK, 0, "sort", &tag_sort, N_("type"), N_("sort tags"),
-			PARSE_OPT_NONEG, parse_opt_sort
-		},
+		OPT_CALLBACK(0 , "sort", sorting_tail, N_("key"),
+			     N_("field name to sort on"), &parse_opt_ref_sorting),
 		{
 			OPTION_CALLBACK, 0, "points-at", &filter.points_at, N_("object"),
 			N_("print only tags of the object"), 0, parse_opt_object_name
@@ -622,7 +360,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 
-	git_config(git_tag_config, NULL);
+	git_config(git_tag_config, sorting_tail);
 
 	memset(&opt, 0, sizeof(opt));
 	memset(&filter, 0, sizeof(filter));
@@ -648,6 +386,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			die(_("--column and -n are incompatible"));
 		colopts = 0;
 	}
+	if (!sorting)
+		sorting = ref_default_sorting();
 	if (cmdmode == 'l') {
 		int ret;
 		if (column_active(colopts)) {
@@ -656,10 +396,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			copts.padding = 2;
 			run_column_filter(colopts, &copts);
 		}
-		if (filter.lines != -1 && tag_sort)
-			die(_("--sort and -n are incompatible"));
 		filter.name_patterns = argv;
-		ret = list_tags(&filter, tag_sort);
+		ret = list_tags(&filter, sorting);
 		if (column_active(colopts))
 			stop_column_filter();
 		return ret;
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index d1ff5c9..51a233f 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1450,13 +1450,7 @@ test_expect_success 'invalid sort parameter on command line' '
 
 test_expect_success 'invalid sort parameter in configuratoin' '
 	git config tag.sort "v:notvalid" &&
-	git tag -l "foo*" >actual &&
-	cat >expect <<-\EOF &&
-	foo1.10
-	foo1.3
-	foo1.6
-	EOF
-	test_cmp expect actual
+	test_must_fail git tag -l "foo*" >actual
 '
 
 test_expect_success 'version sort with prerelease reordering' '
-- 
2.4.6

[PATCH v4 09/10] tag.c: implement '--format' option

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Implement the '--format' option provided by 'ref-filter'.
This lets the user list tags as per desired format similar
to the implementation in 'git for-each-ref'.

Add tests and documentation for the same.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 Documentation/git-tag.txt | 15 ++++++++++++++-
 builtin/tag.c             | 11 +++++++----
 t/t7004-tag.sh            | 16 ++++++++++++++++
 3 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index 02fb363..727d653 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -13,7 +13,8 @@ SYNOPSIS
 	<tagname> [<commit> | <object>]
 'git tag' -d <tagname>...
 'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
-	[--column[=<options>] | --no-column] [--sort=<key>] [<pattern>...]
+	[--column[=<options>] | --no-column] [--sort=<key>] [--format=<format>]
+	[<pattern>...]
 'git tag' -v <tagname>...
 
 DESCRIPTION
@@ -155,6 +156,18 @@ This option is only applicable when listing tags without annotation lines.
 	The object that the new tag will refer to, usually a commit.
 	Defaults to HEAD.
 
+<format>::
+	A string that interpolates `%(fieldname)` from the object
+	pointed at by a ref being shown.  If `fieldname` is prefixed
+	with an asterisk (`*`) and the ref points at a tag object, the
+	value for the field in the object tag refers is used.  When
+	unspecified, defaults to `%(refname:short)`.  It also
+	interpolates `%%` to `%`, and `%xx` where `xx` are hex digits
+	interpolates to character with hex code `xx`; for example
+	`%00` interpolates to `\0` (NUL), `%09` to `\t` (TAB) and
+	`%0a` to `\n` (LF).  The fields are same as those in `git
+	for-each-ref`.
+
 
 CONFIGURATION
 -------------
diff --git a/builtin/tag.c b/builtin/tag.c
index d396872..a8052b4 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -30,10 +30,9 @@ static const char * const git_tag_usage[] = {
 
 static unsigned int colopts;
 
-static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting)
+static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting, const char *format)
 {
 	struct ref_array array;
-	char *format;
 	int i;
 
 	memset(&array, 0, sizeof(array));
@@ -43,7 +42,7 @@ static int list_tags(struct ref_filter *filter, struct ref_sorting *sorting)
 
 	if (filter->lines)
 		format = "%(align:16)%(refname:short)";
-	else
+	else if (!format)
 		format = "%(refname:short)";
 
 	verify_ref_format(format);
@@ -326,6 +325,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	struct strbuf err = STRBUF_INIT;
 	struct ref_filter filter;
 	static struct ref_sorting *sorting = NULL, **sorting_tail = &sorting;
+	const char *format = NULL;
 	struct option options[] = {
 		OPT_CMDMODE('l', "list", &cmdmode, N_("list tag names"), 'l'),
 		{ OPTION_INTEGER, 'n', NULL, &filter.lines, N_("n"),
@@ -357,6 +357,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			OPTION_CALLBACK, 0, "points-at", &filter.points_at, N_("object"),
 			N_("print only tags of the object"), 0, parse_opt_object_name
 		},
+		OPT_STRING(  0 , "format", &format, N_("format"), N_("format to use for the output")),
 		OPT_END()
 	};
 
@@ -396,8 +397,10 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			copts.padding = 2;
 			run_column_filter(colopts, &copts);
 		}
+		if (format && (filter.lines != -1))
+			die(_("--format and -n are incompatible"));
 		filter.name_patterns = argv;
-		ret = list_tags(&filter, sorting);
+		ret = list_tags(&filter, sorting, format);
 		if (column_active(colopts))
 			stop_column_filter();
 		return ret;
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index 51a233f..884c0d3 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1507,4 +1507,20 @@ EOF"
 	test_cmp expect actual
 '
 
+test_expect_success '--format cannot be used with -n' '
+	test_must_fail git tag -l -n4 --format="%(refname)"
+'
+
+test_expect_success '--format should list tags as per format given' '
+	cat >expect <<-\EOF &&
+	refname : refs/tags/foo1.10
+	refname : refs/tags/foo1.3
+	refname : refs/tags/foo1.6
+	refname : refs/tags/foo1.6-rc1
+	refname : refs/tags/foo1.6-rc2
+	EOF
+	git tag -l --format="refname : %(refname)" "foo*" >actual &&
+	test_cmp expect actual
+'
+
 test_done
-- 
2.4.6

[PATCH v4 10/10] tag.c: implement '--merged' and '--no-merged' options

[Karthik Nayak]

From: Karthik Nayak <karthik.188@gmail.com>

Using 'ref-filter' APIs implement the '--merged' and '--no-merged'
options into 'tag.c'. The '--merged' option lets the user to only
list tags merged into the named commit. The '--no-merged' option
lets the user to only list tags not merged into the named commit.
If no object is provided it assumes HEAD as the object.

Add documentation and tests for the same.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 Documentation/git-tag.txt |  7 ++++++-
 builtin/tag.c             |  6 +++++-
 t/t7004-tag.sh            | 27 +++++++++++++++++++++++++++
 3 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index 727d653..2a07d67 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -14,7 +14,7 @@ SYNOPSIS
 'git tag' -d <tagname>...
 'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
 	[--column[=<options>] | --no-column] [--sort=<key>] [--format=<format>]
-	[<pattern>...]
+	[--[no-]merged [<commit>]] [<pattern>...]
 'git tag' -v <tagname>...
 
 DESCRIPTION
@@ -168,6 +168,11 @@ This option is only applicable when listing tags without annotation lines.
 	`%0a` to `\n` (LF).  The fields are same as those in `git
 	for-each-ref`.
 
+--[no-]merged [<commit>]::
+	Only list tags whose tips are reachable, or not reachable
+	if '--no-merged' is used, from the specified commit ('HEAD'
+	if not specified).
+
 
 CONFIGURATION
 -------------
diff --git a/builtin/tag.c b/builtin/tag.c
index a8052b4..23256fc 100644
--- a/builtin/tag.c
+++ b/builtin/tag.c
@@ -23,7 +23,7 @@ static const char * const git_tag_usage[] = {
 	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
 	N_("git tag -d <tagname>..."),
 	N_("git tag -l [-n[<num>]] [--contains <commit>] [--points-at <object>]"
-		"\n\t\t[<pattern>...]"),
+		"\n\t\t[--[no-]merged [<commit>]] [<pattern>...]"),
 	N_("git tag -v <tagname>..."),
 	NULL
 };
@@ -351,6 +351,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
 		OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
 		OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_MERGED(&filter, N_("print only tags that are merged")),
+		OPT_NO_MERGED(&filter, N_("print only tags that are not merged")),
 		OPT_CALLBACK(0 , "sort", sorting_tail, N_("key"),
 			     N_("field name to sort on"), &parse_opt_ref_sorting),
 		{
@@ -411,6 +413,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		die(_("--contains option is only allowed with -l."));
 	if (filter.points_at.nr)
 		die(_("--points-at option is only allowed with -l."));
+	if (filter.merge_commit)
+		die(_("--merged and --no-merged option are only allowed with -l"));
 	if (cmdmode == 'd')
 		return for_each_tag_name(argv, delete_tag);
 	if (cmdmode == 'v')
diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index 884c0d3..e154a32 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1523,4 +1523,31 @@ test_expect_success '--format should list tags as per format given' '
 	test_cmp expect actual
 '
 
+test_expect_success 'setup --merged test tags' '
+	git tag mergetest-1 HEAD~2 &&
+	git tag mergetest-2 HEAD~1 &&
+	git tag mergetest-3 HEAD
+'
+
+test_expect_success '--merged cannot be used in non-list mode' '
+	test_must_fail git tag --merged=mergetest-2 foo
+'
+
+test_expect_success '--merged shows merged tags' '
+	cat >expect <<-\EOF &&
+	mergetest-1
+	mergetest-2
+	EOF
+	git tag -l --merged=mergetest-2 mergetest-* >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--no-merged show unmerged tags' '
+	cat >expect <<-\EOF &&
+	mergetest-3
+	EOF
+	git tag -l --no-merged=mergetest-2 mergetest-* >actual &&
+	test_cmp expect actual
+'
+
 test_done
-- 
2.4.6