Merge branch 'jc/dotdot-is-parent-directory'

"git log .." errored out saying it is both rev range and a path when
there is no disambiguating "--" is on the command line.  Update the
command line parser to interpret ".." as a path in such a case.

* jc/dotdot-is-parent-directory:
  specifying ranges: we did not mean to make ".." an empty set

1 files changed, 14 insertions, 2 deletions

diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index bb3a5161bb..f267a1d3b5 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@@ -230,6 +230,7 @@ static int try_difference(const char *arg)
 	const char *next;
 	const char *this;
 	int symmetric;
+	static const char head_by_default[] = "HEAD";
 
 	if (!(dotdot = strstr(arg, "..")))
 		return 0;
@@ -241,9 +242,20 @@ static int try_difference(const char *arg)
 	next += symmetric;
 
 	if (!*next)
-		next = "HEAD";
+		next = head_by_default;
 	if (dotdot == arg)
-		this = "HEAD";
+		this = head_by_default;
+
+	if (this == head_by_default && next == head_by_default &&
+	    !symmetric) {
+		/*
+		 * Just ".."?  That is not a range but the
+		 * pathspec for the parent directory.
+		 */
+		*dotdot = '.';
+		return 0;
+	}
+
 	if (!get_sha1_committish(this, sha1) && !get_sha1_committish(next, end)) {
 		show_rev(NORMAL, end, next);
 		show_rev(symmetric ? NORMAL : REVERSED, sha1, this);