Merge branch 'nd/gitignore-trailing-whitespace'

Trailing whitespaces in .gitignore files, unless they are quoted for
fnmatch(3), e.g. "path\ ", are warned and ignored.

Strictly speaking, this is a backward incompatible change, but very
unlikely to bite any sane user and adjusting should be obvious and
easy.

* nd/gitignore-trailing-whitespace:
  t0008: skip trailing space test on Windows
  dir: ignore trailing spaces in exclude patterns
  dir: warn about trailing spaces in exclude patterns

Documentation/gitignore.txt

@@ -77,6 +77,9 @@ PATTERN FORMAT
    Put a backslash ("`\`") in front of the first hash for patterns
    that begin with a hash.
 
+ - Trailing spaces are ignored unless they are quoted with backlash
+   ("`\`").
+
  - An optional prefix "`!`" which negates the pattern; any
    matching file excluded by a previous pattern will become
    included again. It is not possible to re-include a file if a parent

dir.c

@@ -503,6 +503,25 @@ void clear_exclude_list(struct exclude_list *el)
 	el->filebuf = NULL;
 }
 
+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';
+}
+
 int add_excludes_from_file_to_list(const char *fname,
 				   const char *base,
 				   int baselen,
@@ -554,6 +573,7 @@ int add_excludes_from_file_to_list(const char *fname,
 		if (buf[i] == '\n') {
 			if (entry != buf + i && entry[0] != '#') {
 				buf[i - (i && buf[i-1] == '\r')] = 0;
+				trim_trailing_spaces(entry);
 				add_exclude(entry, base, baselen, el, lineno);
 			}
 			lineno++;

t/t0008-ignores.sh

@@ -775,4 +775,35 @@ test_expect_success PIPE 'streaming support for --stdin' '
 	echo "$response" | grep "^::	two"
 '
 
+############################################################################
+#
+# test whitespace handling
+
+test_expect_success 'trailing whitespace is ignored' '
+	mkdir whitespace &&
+	>whitespace/trailing &&
+	>whitespace/untracked &&
+	echo "whitespace/trailing   " >ignore &&
+	cat >expect <<EOF &&
+whitespace/untracked
+EOF
+	: >err.expect &&
+	git ls-files -o -X ignore whitespace >actual 2>err &&
+	test_cmp expect actual &&
+	test_cmp err.expect err
+'
+
+test_expect_success !MINGW 'quoting allows trailing whitespace' '
+	rm -rf whitespace &&
+	mkdir whitespace &&
+	>"whitespace/trailing  " &&
+	>whitespace/untracked &&
+	echo "whitespace/trailing\\ \\ " >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