[PATCH 1/3] git-apply: fix whitespace stripping

From: J. Bruce Fields <bfields@citi.umich.edu>
Date: Sep 16, 2007, 22:49 UTC
Message-ID: <11899829424173-git-send-email-bfields@citi.umich.edu>
In-Reply-To: <11899829424040-git-send-email-bfields@citi.umich.edu>

The algorithm isn't right here: it accumulates any set of 8 spaces into tabs even if they're separated by tabs, so

	<four spaces><tab><four spaces><tab>

is converted to

	<tab><tab><tab>

when it should be just

	<tab><tab>

So teach git-apply that a tab hides any group of less than 8 previous spaces in a row.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---
 builtin-apply.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/builtin-apply.c b/builtin-apply.c
index 976ec77..70359c1 100644
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -1642,15 +1642,22 @@ static int apply_line(char *output, const char *patch, int plen)
 
 	buf = output;
 	if (need_fix_leading_space) {
+		int consecutive_spaces = 0;
 		/* between patch[1..last_tab_in_indent] strip the
 		 * funny spaces, updating them to tab as needed.
 		 */
 		for (i = 1; i < last_tab_in_indent; i++, plen--) {
 			char ch = patch[i];
-			if (ch != ' ')
+			if (ch != ' ') {
+				consecutive_spaces = 0;
 				*output++ = ch;
-			else if ((i % 8) == 0)
-				*output++ = '\t';
+			} else {
+				consecutive_spaces++;
+				if (consecutive_spaces == 8) {
+					*output++ = '\t';
+					consecutive_spaces = 0;
+				}
+			}
 		}
 		fixed = 1;
 		i = last_tab_in_indent;

-- 
1.5.3.1.42.gfe5df