dir.c:trim_trailing_spaces(): fix for " \ " sequence

Discard the unnecessary 'nr_spaces' variable, remove 'strlen()' and
improve the 'if' structure.  Switch to pointers instead of integers
to control the loop.

Slightly more rare occurrences of 'text  \    ' with a backslash
in between spaces are handled correctly.  Namely, the code in
7e2e4b37 (dir: ignore trailing spaces in exclude patterns, 2014-02-09)
does not reset 'last_space' when a backslash is encountered and the above
line stays intact as a result.

Add a test at the end of t/t0008-ignores.sh to exhibit this behavior.

Signed-off-by: Pasha Bolokhov <pasha.bolokhov@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/dir.c b/dir.c
index eb6f581270f81a2e844e3396f966e67d06d27f41..797805d6a1d33ef66ccb61155135cdcd1a53d9d0 100644 (file)
--- a/dir.c
+++ b/dir.c
@@ -508,21 +508,25 @@ void clear_exclude_list(struct exclude_list *el)
 
 static void trim_trailing_spaces(char *buf)
 {
-       int i, last_space = -1, nr_spaces, len = strlen(buf);
-       for (i = 0; i < len; i++)
-               if (buf[i] == '\\')
-                       i++;
-               else if (buf[i] == ' ') {
-                       if (last_space == -1) {
-                               last_space = i;
-                               nr_spaces = 1;
-                       } else
-                               nr_spaces++;
-               } else
-                       last_space = -1;
-
-       if (last_space != -1 && last_space + nr_spaces == len)
-               buf[last_space] = '\0';
+       char *p, *last_space = NULL;
+
+       for (p = buf; *p; p++)
+               switch (*p) {
+               case ' ':
+                       if (!last_space)
+                               last_space = p;
+                       break;
+               case '\\':
+                       p++;
+                       if (!*p)
+                               return;
+                       /* fallthrough */
+               default:
+                       last_space = NULL;
+               }
+
+       if (last_space)
+               *last_space = '\0';
 }
 
 int add_excludes_from_file_to_list(const char *fname,

diff --git a/t/t0008-ignores.sh b/t/t0008-ignores.sh
index 63beb99828cc17d2ec8218a6470b62c02a78806b..5ef5ad3db4f6c307e6bcf71f57dcdc4deaafc082 100755 (executable)
--- a/t/t0008-ignores.sh
+++ b/t/t0008-ignores.sh
@@ -806,4 +806,27 @@ test_expect_success !MINGW 'quoting allows trailing whitespace' '
        test_cmp err.expect err
 '
 
+test_expect_success NOT_MINGW,NOT_CYGWIN 'correct handling of backslashes' '
+       rm -rf whitespace &&
+       mkdir whitespace &&
+       >"whitespace/trailing 1  " &&
+       >"whitespace/trailing 2 \\\\" &&
+       >"whitespace/trailing 3 \\\\" &&
+       >"whitespace/trailing 4   \\ " &&
+       >"whitespace/trailing 5 \\ \\ " &&
+       >"whitespace/trailing 6 \\a\\" &&
+       >whitespace/untracked &&
+       echo "whitespace/trailing 1 \\    " >ignore  &&
+       echo "whitespace/trailing 2 \\\\\\\\\\\\\\\\" >>ignore &&
+       echo "whitespace/trailing 3 \\\\\\\\\\\\\\\\ " >>ignore &&
+       echo "whitespace/trailing 4   \\\\\\\\\\\\    " >>ignore &&
+       echo "whitespace/trailing 5 \\\\\\\\ \\\\\\\\\\\\   " >>ignore &&
+       echo "whitespace/trailing 6 \\\\\\\\a\\\\\\\\" >>ignore &&
+       echo whitespace/untracked >expect &&
+       >err.expect &&
+       git ls-files -o -X ignore whitespace >actual 2>err &&
+       test_cmp expect actual &&
+       test_cmp err.expect err
+'
+
 test_done