[PATCH] pretty-format: add append line-feed format specifier

[Harry Jeffery]

Add a new format prefix `_` that causes a line-feed to be inserted
immediately after an expansion if the expansion expands to a non-empty
string. This is useful for when you would like a line for an expansion
to be prepended, but only when the expansion expands to a non empty
string, such as inserting a '%_d' expansion before a commit to show any
refs pointing towards it.
Signed-off-by: Harry Jeffery <ha...@exec64.co.uk>
---
 Documentation/pretty-formats.txt |  4 ++++
 pretty.c                         | 10 ++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/Documentation/pretty-formats.txt 
b/Documentation/pretty-formats.txt
index 85d6353..842cd17 100644
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -197,6 +197,10 @@ 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.

+If you add a `_` (underscore) after '%' of a placeholder, a line-feed
+is inserted immediately after 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 44b9f64..ddb930d 100644
--- a/pretty.c
+++ b/pretty.c
@@ -1416,7 +1416,8 @@ static size_t format_commit_item(struct strbuf 
*sb, /* in UTF-8 */
                NO_MAGIC,
                ADD_LF_BEFORE_NON_EMPTY,
                DEL_LF_BEFORE_EMPTY,
-               ADD_SP_BEFORE_NON_EMPTY
+               ADD_SP_BEFORE_NON_EMPTY,
+               ADD_LF_AFTER_NON_EMPTY
        } magic = NO_MAGIC;

        switch (placeholder[0]) {
@@ -1429,6 +1430,9 @@ static size_t format_commit_item(struct strbuf 
*sb, /* in UTF-8 */
        case ' ':
                magic = ADD_SP_BEFORE_NON_EMPTY;
                break;
+       case '_':
+               magic = ADD_LF_AFTER_NON_EMPTY;
+               break;
        default:
                break;
        }
@@ -1449,6 +1453,8 @@ static size_t format_commit_item(struct strbuf 
*sb, /* in UTF-8 */
        } else if (orig_len != sb->len) {
                if (magic == ADD_LF_BEFORE_NON_EMPTY)
                        strbuf_insert(sb, orig_len, "\n", 1);
+               else if (magic == ADD_LF_AFTER_NON_EMPTY)
+                       strbuf_addch(sb, '\n');
                else if (magic == ADD_SP_BEFORE_NON_EMPTY)
                        strbuf_insert(sb, orig_len, " ", 1);
        }
@@ -1460,7 +1466,7 @@ static size_t userformat_want_item(struct strbuf 
*sb, const char *placeholder,
 {
        struct userformat_want *w = context;

-       if (*placeholder == '+' || *placeholder == '-' || *placeholder == ' ')
+	if (*placeholder == '+' || *placeholder == '-' || *placeholder == ' ' 
|| *placeholder == '_')
                placeholder++;

        switch (*placeholder) {
--
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html