pretty: Introduce ' ' modifier to add space if non-empty

We have the '+' modifiier which helps combine format specifiers which
may possibly be empty, e.g. '%s%+b%n'.

Introduce an analogous ' ' (space) modifier which adds a space before
non-empty items. This helps assemble "one line type" format specifiers.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt
index 8c68ce94f990b0c7f3bc909cc3dc0c4e2a37cf3b..561cc9f7d7ef1a2502d608e59e2eae345bffd685 100644 (file)
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -159,6 +159,10 @@ If you add a `-` (minus sign) after '%' of a placeholder, line-feeds that
 immediately precede the expansion are deleted if and only if the
 placeholder expands to an empty string.
 
+If you add a ` ` (space) after '%' of a placeholder, a space
+is inserted immediately before the expansion if and only if the
+placeholder expands to a non-empty string.
+
 * 'tformat:'
 +
 The 'tformat:' format works exactly like 'format:', except that it

diff --git a/pretty.c b/pretty.c
index 8b18efda9cd6eb615900687c0205daa832794c92..9e845dcb0b7ffca8794b555508b27fe291a0b529 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -942,6 +942,7 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
                NO_MAGIC,
                ADD_LF_BEFORE_NON_EMPTY,
                DEL_LF_BEFORE_EMPTY,
+               ADD_SP_BEFORE_NON_EMPTY,
        } magic = NO_MAGIC;
 
        switch (placeholder[0]) {
@@ -951,6 +952,9 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
        case '+':
                magic = ADD_LF_BEFORE_NON_EMPTY;
                break;
+       case ' ':
+               magic = ADD_SP_BEFORE_NON_EMPTY;
+               break;
        default:
                break;
        }
@@ -965,8 +969,11 @@ static size_t format_commit_item(struct strbuf *sb, const char *placeholder,
        if ((orig_len == sb->len) && magic == DEL_LF_BEFORE_EMPTY) {
                while (sb->len && sb->buf[sb->len - 1] == '\n')
                        strbuf_setlen(sb, sb->len - 1);
-       } else if ((orig_len != sb->len) && magic == ADD_LF_BEFORE_NON_EMPTY) {
-               strbuf_insert(sb, orig_len, "\n", 1);
+       } else if (orig_len != sb->len) {
+               if (magic == ADD_LF_BEFORE_NON_EMPTY)
+                       strbuf_insert(sb, orig_len, "\n", 1);
+               else if (magic == ADD_SP_BEFORE_NON_EMPTY)
+                       strbuf_insert(sb, orig_len, " ", 1);
        }
        return consumed + 1;
 }
@@ -976,7 +983,7 @@ static size_t userformat_want_item(struct strbuf *sb, const char *placeholder,
 {
        struct userformat_want *w = context;
 
-       if (*placeholder == '+' || *placeholder == '-')
+       if (*placeholder == '+' || *placeholder == '-' || *placeholder == ' ')
                placeholder++;
 
        switch (*placeholder) {

diff --git a/t/t6006-rev-list-format.sh b/t/t6006-rev-list-format.sh
index 9b77073df880d4597742e20d738273244d2e4a10..cccacd4add48524abd4a3021f8048a6c45c245ea 100755 (executable)
--- a/t/t6006-rev-list-format.sh
+++ b/t/t6006-rev-list-format.sh
@@ -200,6 +200,16 @@ test_expect_success 'add LF before non-empty (2)' '
        grep "^$" actual
 '
 
+test_expect_success 'add SP before non-empty (1)' '
+       git show -s --pretty=format:"%s% bThanks" HEAD^^ >actual &&
+       test $(wc -w <actual) = 2
+'
+
+test_expect_success 'add SP before non-empty (2)' '
+       git show -s --pretty=format:"%s% sThanks" HEAD^^ >actual &&
+       test $(wc -w <actual) = 4
+'
+
 test_expect_success '--abbrev' '
        echo SHORT SHORT SHORT >expect2 &&
        echo LONG LONG LONG >expect3 &&