pretty: support multiline subjects with format:

git log --pretty=format:%s (and tformat:) used to display the first
line of the subject, unlike the other --pretty options, which would
construct a subject line from all lines of the first paragraph of
the commit message.

For consistency and increased code reuse, change format: to do the
same as the other options.

Before:
	$ git log --pretty=oneline v1.6.1 | md5sum
	7c0896d2a94fc3315a0372b9b3373a8f  -
	$ git log --pretty=tformat:"%H %s" v1.6.1 | md5sum
	298903b1c065002e15daa5329213c51f  -

After:
	$ git log --pretty=tformat:"%H %s" v1.6.1 | md5sum
	7c0896d2a94fc3315a0372b9b3373a8f  -
	$ git log --pretty=oneline v1.6.1 | md5sum
	7c0896d2a94fc3315a0372b9b3373a8f  -

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/pretty.c b/pretty.c
index 632abc5231fe10831aed1e127b0b46f4fd632d46..343dca556cc73031bb073b6ebf8bf511db3a60c4 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -424,13 +424,15 @@ struct chunk {
 struct format_commit_context {
        const struct commit *commit;
        enum date_mode dmode;
+       unsigned commit_header_parsed:1;
+       unsigned commit_message_parsed:1;
 
        /* These offsets are relative to the start of the commit message. */
-       int commit_header_parsed;
-       struct chunk subject;
        struct chunk author;
        struct chunk committer;
        struct chunk encoding;
+       size_t message_off;
+       size_t subject_off;
        size_t body_off;
 
        /* The following ones are relative to the result struct strbuf. */
@@ -460,23 +462,14 @@ static void parse_commit_header(struct format_commit_context *context)
 {
        const char *msg = context->commit->buffer;
        int i;
-       enum { HEADER, SUBJECT, BODY } state;
 
-       for (i = 0, state = HEADER; msg[i] && state < BODY; i++) {
+       for (i = 0; msg[i]; i++) {
                int eol;
                for (eol = i; msg[eol] && msg[eol] != '\n'; eol++)
                        ; /* do nothing */
 
-               if (state == SUBJECT) {
-                       context->subject.off = i;
-                       context->subject.len = eol - i;
-                       i = eol;
-               }
                if (i == eol) {
-                       state++;
-                       /* strip empty lines */
-                       while (msg[eol] == '\n' && msg[eol + 1] == '\n')
-                               eol++;
+                       break;
                } else if (!prefixcmp(msg + i, "author ")) {
                        context->author.off = i + 7;
                        context->author.len = eol - i - 7;
@@ -488,10 +481,8 @@ static void parse_commit_header(struct format_commit_context *context)
                        context->encoding.len = eol - i - 9;
                }
                i = eol;
-               if (!msg[i])
-                       break;
        }
-       context->body_off = i;
+       context->message_off = i;
        context->commit_header_parsed = 1;
 }
 
@@ -508,6 +499,8 @@ static const char *format_subject(struct strbuf *sb, const char *msg,
                if (!linelen || is_empty_line(line, &linelen))
                        break;
 
+               if (!sb)
+                       continue;
                strbuf_grow(sb, linelen + 2);
                if (!first)
                        strbuf_addstr(sb, line_separator);
@@ -517,6 +510,21 @@ static const char *format_subject(struct strbuf *sb, const char *msg,
        return msg;
 }
 
+static void parse_commit_message(struct format_commit_context *c)
+{
+       const char *msg = c->commit->buffer + c->message_off;
+       const char *start = c->commit->buffer;
+
+       msg = skip_empty_lines(msg);
+       c->subject_off = msg - start;
+
+       msg = format_subject(NULL, msg, NULL);
+       msg = skip_empty_lines(msg);
+       c->body_off = msg - start;
+
+       c->commit_message_parsed = 1;
+}
+
 static void format_decoration(struct strbuf *sb, const struct commit *commit)
 {
        struct name_decoration *d;
@@ -636,9 +644,6 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
                parse_commit_header(c);
 
        switch (placeholder[0]) {
-       case 's':       /* subject */
-               strbuf_add(sb, msg + c->subject.off, c->subject.len);
-               return 1;
        case 'a':       /* author ... */
                return format_person_part(sb, placeholder[1],
                                   msg + c->author.off, c->author.len,
@@ -650,6 +655,16 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
        case 'e':       /* encoding */
                strbuf_add(sb, msg + c->encoding.off, c->encoding.len);
                return 1;
+       }
+
+       /* Now we need to parse the commit message. */
+       if (!c->commit_message_parsed)
+               parse_commit_message(c);
+
+       switch (placeholder[0]) {
+       case 's':       /* subject */
+               format_subject(sb, msg + c->subject_off, " ");
+               return 1;
        case 'b':       /* body */
                strbuf_addstr(sb, msg + c->body_off);
                return 1;