pretty: support %>> that steal trailing spaces

This is pretty useful in `%<(100)%s%Cred%>(20)% an' where %s does not
use up all 100 columns and %an needs more than 20 columns. By
replacing %>(20) with %>>(20), %an can steal spaces from %s.

%>> understands escape sequences, so %Cred does not stop it from
stealing spaces in %<(100).

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt
index d3450bf96fb9385bfaae2c1048c4c44dda3a1052..c96ff41fd51ffa10ff0cbcf5ef448f8141c68695 100644 (file)
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -173,7 +173,10 @@ The placeholders are:
   columns, padding spaces on the right if necessary
 - '%>(<N>)', '%>|(<N>)': similar to '%<(<N>)', '%<|(<N>)'
   respectively, but padding spaces on the left
-- '%><(<N>)', '%><|(<N>)': similar to '%<(<N>)', '%<|(<N>)'
+- '%>>(<N>)', '%>>|(<N>)': similar to '%>(<N>)', '%>|(<N>)'
+  respectively, except that if the next placeholder takes more spaces
+  than given and there are spaces on its left, use those spaces
+- '%><(<N>)', '%><|(<N>)': similar to '% <(<N>)', '%<|(<N>)'
   respectively, but padding both sides (i.e. the text is centered)
 
 NOTE: Some placeholders may depend on other options given to the

diff --git a/pretty.c b/pretty.c
index f7c6442e711d07cb8941a6a2b5d9f7f8b9b7ea2d..d59579a2c0190a397fd0ceb5e051d241f731f5ed 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -773,6 +773,7 @@ enum flush_type {
        no_flush,
        flush_right,
        flush_left,
+       flush_left_and_steal,
        flush_both
 };
 
@@ -1026,6 +1027,9 @@ static size_t parse_padding_placeholder(struct strbuf *sb,
                if (*ch == '<') {
                        flush_type = flush_both;
                        ch++;
+               } else if (*ch == '>') {
+                       flush_type = flush_left_and_steal;
+                       ch++;
                } else
                        flush_type = flush_left;
                break;
@@ -1334,6 +1338,36 @@ static size_t format_and_pad_commit(struct strbuf *sb, /* in UTF-8 */
                total_consumed++;
        }
        len = utf8_strnwidth(local_sb.buf, -1, 1);
+
+       if (c->flush_type == flush_left_and_steal) {
+               const char *ch = sb->buf + sb->len - 1;
+               while (len > padding && ch > sb->buf) {
+                       const char *p;
+                       if (*ch == ' ') {
+                               ch--;
+                               padding++;
+                               continue;
+                       }
+                       /* check for trailing ansi sequences */
+                       if (*ch != 'm')
+                               break;
+                       p = ch - 1;
+                       while (ch - p < 10 && *p != '\033')
+                               p--;
+                       if (*p != '\033' ||
+                           ch + 1 - p != display_mode_esc_sequence_len(p))
+                               break;
+                       /*
+                        * got a good ansi sequence, put it back to
+                        * local_sb as we're cutting sb
+                        */
+                       strbuf_insert(&local_sb, 0, p, ch + 1 - p);
+                       ch = p - 1;
+               }
+               strbuf_setlen(sb, ch + 1 - sb->buf);
+               c->flush_type = flush_left;
+       }
+
        if (len > padding) {
                switch (c->truncate) {
                case trunc_left:

diff --git a/t/t4205-log-pretty-formats.sh b/t/t4205-log-pretty-formats.sh
index b8685b97f99e568e88c4add70b8f2841ec742267..26fbfde4a36689a51c181c13f9d5680fd2780219 100755 (executable)
--- a/t/t4205-log-pretty-formats.sh
+++ b/t/t4205-log-pretty-formats.sh
@@ -260,4 +260,18 @@ EOF
        test_cmp expected actual
 '
 
+test_expect_success 'left/right alignment formatting with stealing' '
+       git commit --amend -m short --author "long long long <long@me.com>" &&
+       git log --pretty="format:%<(10,trunc)%s%>>(10,ltrunc)% an" >actual &&
+       # complete the incomplete line at the end
+       echo >>actual &&
+       cat <<\EOF >expected &&
+short long  long long
+message ..   A U Thor
+add bar      A U Thor
+initial      A U Thor
+EOF
+       test_cmp expected actual
+'
+
 test_done

diff --git a/utf8.c b/utf8.c
index 197414af4c7cd257ea46f93ea52254c231ab9a63..b1e13035f5055caec66a16ff30371d97886cade2 100644 (file)
--- a/utf8.c
+++ b/utf8.c
@@ -9,7 +9,7 @@ struct interval {
   int last;
 };
 
-static size_t display_mode_esc_sequence_len(const char *s)
+size_t display_mode_esc_sequence_len(const char *s)
 {
        const char *p = s;
        if (*p++ != '\033')

diff --git a/utf8.h b/utf8.h
index edde8ee189398f8d6fb8dcd53e5c6da9d0a67884..32a7bfb987dcc487bcfc49f1b9f2ab29803a0070 100644 (file)
--- a/utf8.h
+++ b/utf8.h
@@ -3,6 +3,7 @@
 
 typedef unsigned int ucs_char_t;  /* assuming 32bit int */
 
+size_t display_mode_esc_sequence_len(const char *s);
 int utf8_width(const char **start, size_t *remainder_p);
 int utf8_strnwidth(const char *string, int len, int skip_ansi);
 int utf8_strwidth(const char *string);