diff: add --compact-summary option to complement --stat

This is partly inspired by gerrit web interface which shows diffstat like this, e.g. with commit 0433d533f1 (notice the "A" column on the third line):

    Documentation/merge-config.txt     |  4 +
    builtin/merge.c                    |  2 +
  A t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++
    t/t7612-merge-verify-signatures.sh | 45 ++++++++++
  4 files changed, 132 insertions(+)

In other words, certain information currently shown with --summary is embedded in the diffstat. This helps reading (all information of the same file in the same line instead of two) and can reduce the number of lines if you add/delete a lot of files.

The new option --compact-summary implements this with a tweak to support mode change, which is shown in --summary too.

For mode changes, executable bit is denoted as "(+x)" or "(-x)" when it's added or removed respectively. The same for when a regular file is replaced with a symlink "(+l)" or the other way "(-l)". This also applies to new files. New regulare files are "A", while new executable files or symlinks are "A+x" or "A+l".

Note, there is still one piece of information missing from --summary, the rename/copy percentage. That could probably be added later. It's not as useful as the others anyway.

Signed-off-by Nguyễn Thái Ngọc Duy <[email protected]>

---
I have had something similar for years but the data is shown after the path name instead (it's incidentally shown in the diffstat right below). I was going to clean it up and submit it again, but my recent experience with Gerrit changed my mind a bit about the output.

Documentation/diff-options.txt | 11 ++++
diff.c | 64
+++++++++++++++++++++-

diff.h                                             |  1 +
t/t4013-diff-various.sh                            |  5 ++
...y_--root_--stat_--compact-summary_initial (new) | 12 ++++
...R_--root_--stat_--compact-summary_initial (new) | 12 ++++
...ree_--stat_--compact-summary_initial_mode (new) |  4 ++
..._-R_--stat_--compact-summary_initial_mode (new) |  4 ++
8 files changed, 110 insertions(+), 3 deletions(-)

create mode 100644 t/t4013/diff.diff-tree_--pretty_--root_--stat_--compact-summary_initial create mode 100644 t/t4013/diff.diff-tree_--pretty_-R_--root_--stat_--compact-summary_initial create mode 100644 t/t4013/diff.diff-tree_--stat_--compact-summary_initial_mode create mode 100644 t/t4013/diff.diff-tree_-R_--stat_--compact-summary_initial_mode

Documentation/diff-options.txt +0 -0

index 9d1586b956..ff93ff74d0 100644
@@ -188,6 +188,17 @@ and accumulating child directory counts in the parent 

directories:
Output a condensed summary of extended header information such as creations, renames and mode changes.

+--compact-summary::
+ Output a condensed summary of extended header information in
+ front of the file name part of diffstat. This option is
+ ignored if --stat is not specified.
++
+Fle creations or deletions are denoted with "A" or "D" respectively,

Documentation/diff-options.txt +5 -0

+optionally "+l" if it's a symlink, or "+x" if it's executable.
+Mode changes are put in brackets, e.g. "+x" or "-x" for adding or
+removing executable bit respectively, "+l" or "-l" for becoming a
+symlink or a regular file.
+

ifndef::git-format-patch[]
--patch-with-stat::
Synonym for -p --stat.

diff.c +2 -0

index fb22b19f09..3f6767777d 100644
@@ -2131,6 +2131,7 @@ struct diffstat_t {
 char *from_name;
 char *name;
 char *print_name;
+ const char *status_code;
 unsigned is_unmerged:1;
 unsigned is_binary:1;
 unsigned is_renamed:1;

@@ -2271,6 +2272,7 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 {
 int i, len, add, del, adds = 0, dels = 0;
 uintmax_t max_change = 0, max_len = 0;
+ int max_status_len = 0;
 int total_files = data->nr, count;
 int width, name_width, graph_width, number_width = 0, bin_width = 0;

const char *reset, *add_c, *del_c;

diff.c +12 -0

@@ -2287,6 +2289,18 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 add_c = diff_get_color_opt(options, DIFF_FILE_NEW);
 del_c = diff_get_color_opt(options, DIFF_FILE_OLD);
 
+ for (i = 0; (i < count) && (i < data->nr); i++) {
+ const struct diffstat_file *file = data->files[i];
+ int len;
+
+ if (!file->status_code)
+ continue;
+ len = strlen(file->status_code) + 1;
+
+ if (len > max_status_len)
+ max_status_len = len;
+ }
+
 /*
 * Find the longest filename and max number of changes

*/

diff.c +2 -0

@@ -2383,6 +2397,8 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
       options->stat_name_width < max_len) ?
 options->stat_name_width : max_len;
 
+ name_width += max_status_len;
+
 /*
 * Adjust adjustable widths not to exceed maximum width

*/

diff.c +2 -0

@@ -2402,6 +2418,8 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 graph_width = width - number_width - 6 - name_width;
 }
 
+ name_width -= max_status_len;
+
 /*
 * From here name_width is the width of the name area,

* and graph_width is the width of the graph area.

diff.c +1 -0

@@ -2409,6 +2427,7 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 */
 for (i = 0; i < count; i++) {
 const char *prefix = "";
+ const char *status_code = "";
 struct diffstat_file *file = data->files[i];
 char *name = file->print_name;

uintmax_t added = file->added;

diff.c +3 -0

@@ -2418,6 +2437,9 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 if (!file->is_interesting && (added + deleted == 0))
 continue;
 
+ if (file->status_code)
+ status_code = file->status_code;
+
 /*
 * "scale" the filename

*/

diff.c +3 -1

@@ -2434,7 +2456,9 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 }
 
 if (file->is_binary) {
- strbuf_addf(&out, " %s%-*s |", prefix, len, name);
+ strbuf_addf(&out, " %-*s%s%-*s |",
+     max_status_len, status_code,
+     prefix, len, name);
 strbuf_addf(&out, " %*s", number_width, "Bin");
 if (!added && !deleted) {

strbuf_addch(&out, '\n');

diff.c +3 -1

@@ -2455,7 +2479,9 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 continue;
 }
 else if (file->is_unmerged) {
- strbuf_addf(&out, " %s%-*s |", prefix, len, name);
+ strbuf_addf(&out, " %-*s%s%-*s |",
+     max_status_len, status_code,
+     prefix, len, name);
 strbuf_addstr(&out, " Unmerged\n");
 emit_diff_symbol(options, DIFF_SYMBOL_STATS_LINE,

out.buf, out.len, 0);

diff.c +3 -1

@@ -2482,7 +2508,9 @@ static void show_stats(struct diffstat_t *data, 
 struct diff_options *options)
 add = total - del;
 }
 }
- strbuf_addf(&out, " %s%-*s |", prefix, len, name);
+ strbuf_addf(&out, " %-*s%s%-*s |",
+     max_status_len, status_code,
+     prefix, len, name);
 strbuf_addf(&out, " %*"PRIuMAX"%s",
 number_width, added + deleted,

added + deleted ? " " : "");

diff.c +26 -0

@@ -3248,6 +3276,32 @@ static void builtin_diff(const char *name_a,
 return;
 }
 
+static const char *get_compact_summary(const struct diff_filepair *p, int 
 is_renamed)
+{
+ if (!is_renamed) {
+ if (p->status == DIFF_STATUS_ADDED) {
+ if (S_ISLNK(p->two->mode))
+ return "A+l";
+ else if ((p->two->mode & 0777) == 0755)
+ return "A+x";
+ else
+ return "A";
+ } else if (p->status == DIFF_STATUS_DELETED)
+ return "D";
+ }
+ if (S_ISLNK(p->one->mode) && !S_ISLNK(p->two->mode))
+ return "(-l)";
+ else if (!S_ISLNK(p->one->mode) && S_ISLNK(p->two->mode))
+ return "(+l)";
+ else if ((p->one->mode & 0777) == 0644 &&
+ (p->two->mode & 0777) == 0755)
+ return "(+x)";
+ else if ((p->one->mode & 0777) == 0755 &&
+ (p->two->mode & 0777) == 0644)
+ return "(-x)";
+ return NULL;
+}
+
 static void builtin_diffstat(const char *name_a, const char *name_b,
      struct diff_filespec *one,

struct diff_filespec *two,

diff.c +2 -0

@@ -3267,6 +3321,8 @@ static void builtin_diffstat(const char *name_a, 
 const char *name_b,
 
 data = diffstat_add(diffstat, name_a, name_b);
 data->is_interesting = p->status != DIFF_STATUS_UNKNOWN;
+ if (o->flags.compact_summary)
+ data->status_code = get_compact_summary(p, data->is_renamed);
 
 if (!one || !two) {

data->is_unmerged = 1;

diff.c +2 -0

@@ -4537,6 +4593,8 @@ int diff_opt_parse(struct diff_options *options,
 else if (starts_with(arg, "--stat"))
 /* --stat, --stat-width, --stat-name-width, or --stat-count */
 return stat_opt(options, av);
+ else if (!strcmp(arg, "--compact-summary"))
+ options->flags.compact_summary = 1;
 
 /* renames options */
 else if (starts_with(arg, "-B") ||

diff.h +1 -0

index 7cf276f077..843276196c 100644
@@ -93,6 +93,7 @@ struct diff_flags {
 unsigned funccontext:1;
 unsigned pickaxe_ignore_case:1;
 unsigned default_follow_renames:1;
+ unsigned compact_summary:1;
 };
 
 static inline void diff_flags_or(struct diff_flags *a,

t/t4013-diff-various.sh +0 -0

index f10798b2df..3f9a24fd56 100755
@@ -361,6 +361,11 @@ diff --no-index --raw dir2 dir

diff --no-index --raw --abbrev=4 dir2 dir :noellipses diff --no-index --raw --abbrev=4 dir2 dir diff --no-index --raw --no-abbrev dir2 dir

t/t4013-diff-various.sh +5 -0

+
+diff-tree --pretty --root --stat --compact-summary initial
+diff-tree --pretty -R --root --stat --compact-summary initial
+diff-tree --stat --compact-summary initial mode
+diff-tree -R --stat --compact-summary initial mode

EOF

test_expect_success 'log -S requires an argument' '

(quoted diff) +0 -0

new file mode 100644
index 0000000000..0f086907fc

b/t/t4013/diff.diff-tree_--pretty_--root_--stat_--compact-summary_initial

t/t4013/diff.diff-tree_--pretty_--root_--stat_--compact-summary_initial new file +12 -0

@@ -0,0 +1,12 @@
+$ git diff-tree --pretty --root --stat --compact-summary initial
+commit 444ac553ac7612cc88969031b02b3767fb8a353a
+Author: A U Thor <[email protected]>
+Date:   Mon Jun 26 00:00:00 2006 +0000
+
+    Initial
+
+ A dir/sub | 2 ++
+ A file0   | 3 +++
+ A file2   | 3 +++
+ 3 files changed, 8 insertions(+)
+$

(quoted diff) +0 -0

new file mode 100644
index 0000000000..eeed5872e0

b/t/t4013/diff.diff-tree_--pretty_-R_--root_--stat_--compact-summary_initial

t/t4013/diff.diff-tree_--pretty_-R_--root_--stat_--compact-summary_initial new file +12 -0

@@ -0,0 +1,12 @@
+$ git diff-tree --pretty -R --root --stat --compact-summary initial
+commit 444ac553ac7612cc88969031b02b3767fb8a353a
+Author: A U Thor <[email protected]>
+Date:   Mon Jun 26 00:00:00 2006 +0000
+
+    Initial
+
+ D dir/sub | 2 --
+ D file0   | 3 ---
+ D file2   | 3 ---
+ 3 files changed, 8 deletions(-)
+$

t/t4013/diff.diff-tree_--stat_--compact-summary_initial_mode new file +4 -0

new file mode 100644
index 0000000000..b674ef9c31
@@ -0,0 +1,4 @@
+$ git diff-tree --stat --compact-summary initial mode
+ (+x) file0 | 0
+ 1 file changed, 0 insertions(+), 0 deletions(-)
+$

t/t4013/diff.diff-tree_-R_--stat_--compact-summary_initial_mode new file +4 -0

new file mode 100644
index 0000000000..877e9ae19d
@@ -0,0 +1,4 @@
+$ git diff-tree -R --stat --compact-summary initial mode
+ (-x) file0 | 0
+ 1 file changed, 0 insertions(+), 0 deletions(-)
+$

Signature · 1 line

2.15.1.600.g899a5f85c6

[snip]

For mode changes, executable bit is denoted as "(+x)" or "(-x)" when it's added or removed respectively. The same for when a regular file is replaced with a symlink "(+l)" or the other way "(-l)". This also applies to new files. New regulare files are "A", while new executable files or symlinks are "A+x" or "A+l".

Quoted 7 lines · Nguyễn Thái Ngọc Duy

[snip]

For mode changes, executable bit is denoted as "(+x)" or "(-x)" when it's added or removed respectively. The same for when a regular file is replaced with a symlink "(+l)" or the other way "(-l)". This also applies to new files. New regulare files are "A", while new executable files or symlinks are "A+x" or "A+l".

I like the short summary. However I find the use of parentheses inconsistent.

Why not use them either always (also for "(A+l)")
or never? Was there a specific reason why you added them just in one place?

[...]
The new option --compact-summary implements this with a tweak to support mode change, which is shown in --summary too.

For mode changes, executable bit is denoted as "M+x" or "M-x" when it's added or removed respectively. The same for when a regular file is replaced with a symlink "M+l" or the other way "M-l". This also applies to new files. New regulare files are "A", while new executable files or

Documentation/diff-options.txt and accumulating child directory counts in the parent directories: · line 191

Quoted 6 lines

Documentation/diff-options.txt +4 -0

@@ -188,6 +188,17 @@ and accumulating child directory counts in the parent directories:
+--compact-summary::
+       Output a condensed summary of extended header information in
+       front of the file name part of diffstat. This option is
+       ignored if --stat is not specified.

Rather than ignoring this option if --stat is not specified, a different approach would be for --compact-summary to imply --stat.

Also, per documentation:

    --stat[=<width>[,<name-width>[,<count>]]]::

    These parameters can also be set individually with `--stat-width=<width>`,
    `--stat-name-width=<name-width>` and `--stat-count=<count>`.

One wonders if "compact" could be another modifier recognized by --stat.

(Genuine questions/observations; I haven't formed strong opinions either way.)

This is partly inspired by gerrit web interface which shows diffstat like this, e.g. with commit 0433d533f1 (notice the "A" column on the third line):

     Documentation/merge-config.txt     |  4 +
     builtin/merge.c                    |  2 +
   A t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 ++++++++++
   4 files changed, 132 insertions(+)

In other words, certain information currently shown with --summary is embedded in the diffstat. This helps reading (all information of the same file in the same line instead of two) and can reduce the number of lines if you add/delete a lot of files.

+File creations or deletions are denoted wigth "A" or "D" respectively,

Wait, isn't there a bug here in the existing --summary code, its documentation says it'll show information "such as creations, renames and mode changes".

But even though your --compact-summary shows that the file is being added and its mode changed:

    $ diff -ru <(./git-show --stat 0433d533f1) <(./git-show --stat --compact-summary 0433d533f1)
    --- /dev/fd/63  2018-01-18 21:11:51.186570555 +0000
    +++ /dev/fd/62  2018-01-18 21:11:51.186570555 +0000
    @@ -14,8 +14,8 @@
           t: add tests for pull --verify-signatures
           merge: add config option for verifySignatures

    - Documentation/merge-config.txt     |  4 ++
    - builtin/merge.c                    |  2 +
    - t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++++++++++++++++++++++
    - t/t7612-merge-verify-signatures.sh | 45 +++++++++++++++++++++
    +     Documentation/merge-config.txt     |  4 ++
    +     builtin/merge.c                    |  2 +
    + A+x t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++++++++++++++++++
    +     t/t7612-merge-verify-signatures.sh | 45 +++++++++++++++++++
      4 files changed, 132 insertions(+)

There is no difference between --stat with and without --summary on the same commit, shouldn't it show "create mode [...]" ?

E.g. 95450bbbaa will do the trick for both:

    $ diff -ru <(./git-show --stat 95450bbbaa) <(./git-show --stat --summary 95450bbbaa)
    --- /dev/fd/63  2018-01-18 21:14:20.770050599 +0000
    +++ /dev/fd/62  2018-01-18 21:14:20.770050599 +0000
    @@ -14,3 +14,4 @@
      git-svn.perl                    |  1 +
      t/t9169-git-svn-dcommit-crlf.sh | 27 +++++++++++++++++++++++++++
      2 files changed, 28 insertions(+)
    + create mode 100755 t/t9169-git-svn-dcommit-crlf.sh

    $ diff -ru <(./git-show --stat --summary 95450bbbaa) <(./git-show --stat --compact-summary 95450bbbaa)
    --- /dev/fd/63  2018-01-18 21:14:30.646016210 +0000
    +++ /dev/fd/62  2018-01-18 21:14:30.646016210 +0000
    @@ -11,7 +11,6 @@
         Reported-by: Brian Bennett <[email protected]>
         Signed-off-by: Eric Wong <[email protected]>

    - git-svn.perl                    |  1 +
    - t/t9169-git-svn-dcommit-crlf.sh | 27 +++++++++++++++++++++++++++
    +     git-svn.perl                    |  1 +
    + A+x t/t9169-git-svn-dcommit-crlf.sh | 27 +++++++++++++++++++++++++++
      2 files changed, 28 insertions(+)

- create mode 100755 t/t9169-git-svn-dcommit-crlf.sh

This is partly inspired by gerrit web interface which shows diffstat like this, e.g. with commit 0433d533f1 (notice the "A" column on the third line):

     Documentation/merge-config.txt     |  4 +
     builtin/merge.c                    |  2 +
   A t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 ++++++++++
   4 files changed, 132 insertions(+)

The new option --compact-summary implements this with a tweak to support mode change, which is shown in --summary too.

Quoted 9 lines · Nguyễn Thái Ngọc Duy

This is partly inspired by gerrit web interface which shows diffstat like this, e.g. with commit 0433d533f1 (notice the "A" column on the third line):

     Documentation/merge-config.txt     |  4 +
     builtin/merge.c                    |  2 +
   A t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 ++++++++++
   4 files changed, 132 insertions(+)

I like the general concept. Perusing "git log" output, though, it felt like the summary column was very close to the filenames. What do you think of putting it after the "|", where it is only close to a number?

Something like the patch below (on top of yours, but it probably needs tweaked further for graph_width), which gives:

   t/t5573-pull-verify-signatures.sh | A+x  78 ++++++++++++++++++++++++++++

(I know this is a bikeshed, so I'm perfectly willing to take "yuck, I don't like that as well" as a response).

Quoted 2 lines

The new option --compact-summary implements this with a tweak to support mode change, which is shown in --summary too.

One thing I noticed is that --compact-summary by itself does nothing. Should it imply --stat?

Quoted 2 lines

(I know this is a bikeshed, so I'm perfectly willing to take "yuck, I don't like that as well" as a response).

The position of A+x column is exactly where gerrit put it. Though web pages have more flexibility than our terminal console so its position does not have to be the same. I'm just throwing options out there

For many years I have this instead

 t/t5573-pull-verify-signatures.sh (new +x) | 81 ++++++++++++++++++++

Another option is just wrap the code in [] to make it look like check boxes. But that wastes two more columns

       builtin/merge.c                    |  2 +
 [A+x] t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++++++++
       t/t7612-merge-verify-signatures.sh | 45 +++++++++++++

Back to your suggestion, I kinda like the closeness between the +/- count and "|" though. The output on 10c78a162f is like this, which makes "A" looks a bit umm.. disconnected from the path name?

  Documentation/RelNotes/2.14.0.txt | A  97 +++++++++++++++++++++++++++
  GIT-VERSION-GEN                   |     2 +-
  RelNotes                          |     2 +-

Quoted 2 lines

One thing I noticed is that --compact-summary by itself does nothing. Should it imply --stat?

It might go with --numstat or --dirstat in future too. Didn't really think hard about this yet. But I probably will go with Eric suggestion and keep this in --stat=.... unless it really makes sense to have something like this in --numstat or --dirstat.

     Documentation/merge-config.txt     |  4 +
     builtin/merge.c                    |  2 +
   A t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 ++++++++++
   4 files changed, 132 insertions(+)

...
With this tweak, the actual printout is like this

     Documentation/merge-config.txt     |  4 ++
     builtin/merge.c                    |  2 +
 A+x t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 +++++++++++++
 4 files changed, 132 insertions(+)

Quoted 5 lines

     Documentation/merge-config.txt     |  4 ++
     builtin/merge.c                    |  2 +
 A+x t/t5573-pull-verify-signatures.sh  | 81 ++++++++++++++++++++++++
     t/t7612-merge-verify-signatures.sh | 45 +++++++++++++
 4 files changed, 132 insertions(+)

I like the concept but given that additions and mode changes are rare events, I am not so sure if it is worth always wasting three columns like the above. Assuming that this is solely meant for human consumption and machine parsability is of no concern, I actually prefer the output format you said you've been using your personal fork, e.g.

 Documentation/merge-config.txt              |  4 ++
 builtin/merge.c                             |  2 +
 t/t5573-pull-verify-signatures.sh (new, +x) | 81 ++++++++++++++++++++++++
 t/t7612-merge-verify-signatures.sh          | 45 +++++++++++++

That is

(1) do not change the starting column at the leftmost end, and
(2) do not permanently allocate the columns for "compact" summary.