Stick to the best name in the reversed-patch check

* src/pch.c (intuit_diff_type): Fix a bug where the reversed-patch
check would wrongly pick the last name instead of the best name.
* src/create-delete: Add test cases for that.

3 files changed, 38 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 7df3427..740ff79 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2009-05-02  Andreas Gruenbacher  <agruen@suse.de>
 
+	* src/pch.c (intuit_diff_type): Fix a bug where the reversed-patch
+	check would wrongly pick the last name instead of the best name.
+	* src/create-delete: Add test cases for that.
+
 	* src/pch.c (fetchmode): Document that the "diff --git" format does
 	not store file permissions of symlinks.
 	* src/util.c (set_file_attributes): Since we don't have symlink file
diff --git a/src/pch.c b/src/pch.c
index db50892..74e010c 100644
--- a/src/pch.c
+++ b/src/pch.c
@@ -843,9 +843,10 @@ intuit_diff_type (bool need_header, mode_t *p_file_type)
 
 	    if (i0 != NONE
 		&& (i == NONE || (st[i].st_mode & S_IFMT) == file_type)
-	        && maybe_reverse (p_name[i0], i == NONE,
-				  i == NONE || st[i].st_size == 0))
-		i = i0;
+		&& maybe_reverse (p_name[i == NONE ? i0 : i], i == NONE,
+				  i == NONE || st[i].st_size == 0)
+		&& i == NONE)
+	      i = i0;
 
 	    if (i == NONE && p_says_nonexistent[reverse])
 	      {
diff --git a/tests/create-delete b/tests/create-delete
index c71de21..5b3d9c8 100644
--- a/tests/create-delete
+++ b/tests/create-delete
@@ -113,3 +113,33 @@ Hunk #1 FAILED at 1.
 1 out of 1 hunk FAILED -- saving rejects to file f.rej
 Status: 1
 EOF
+
+# ==============================================================
+
+: > f.orig
+echo f > f
+diff -u f f.orig > f.diff
+mv f.orig f
+check 'patch -p0 -t < f.diff || echo "Status: $?"' <<EOF
+The next patch would empty out the file f,
+which is already empty!  Assuming -R.
+patching file f
+EOF
+
+check 'cat f' <<EOF
+f
+EOF
+
+: > f.orig
+echo f > f
+diff -u f /dev/null > f.diff
+mv f.orig f
+check 'patch -p0 -t < f.diff || echo "Status: $?"' <<EOF
+The next patch would empty out the file f,
+which is already empty!  Assuming -R.
+patching file f
+EOF
+
+check 'cat f' <<EOF
+f
+EOF