branch: warn and refuse to set a branch as a tracking branch of itself.

diff --git a/dir.c b/dir.c
index 6b1c47822fd725d7d71871c806b9f631555985db..3a8d3e67a529c03659dc950d64f4b0d6226f9925 100644 (file)
--- a/dir.c
+++ b/dir.c
@@ -891,12 +891,20 @@ int is_empty_dir(const char *path)
        return ret;
 }
 
-int remove_dir_recursively(struct strbuf *path, int only_empty)
+int remove_dir_recursively(struct strbuf *path, int flag)
 {
-       DIR *dir = opendir(path->buf);
+       DIR *dir;
        struct dirent *e;
        int ret = 0, original_len = path->len, len;
+       int only_empty = (flag & REMOVE_DIR_EMPTY_ONLY);
+       unsigned char submodule_head[20];
 
+       if ((flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
+           !resolve_gitlink_ref(path->buf, "HEAD", submodule_head))
+               /* Do not descend and nuke a nested git work tree. */
+               return 0;
+
+       dir = opendir(path->buf);
        if (!dir)
                return -1;
        if (path->buf[original_len - 1] != '/')