Merge branch 'dt/untracked-subdir'

The experimental untracked-cache feature were buggy when paths with
a few levels of subdirectories are involved.

* dt/untracked-subdir:
untracked cache: fix entry invalidation
untracked-cache: fix subdirectory handling

diff --combined dir.c
index c00c7e2b73603589ae1e3f49abcd931f4e761850,c1edabf34d5a1e3466a71bd679d3fd6cf50fc5ee..7b25634832716ade46686d118184c4d43d8c11e7
--- 1/dir.c
--- 2/dir.c
+++ b/dir.c
@@@ -1297,7 -1297,7 +1297,7 @@@ static enum exist_status directory_exis
   */
  static enum path_treatment treat_directory(struct dir_struct *dir,
        struct untracked_cache_dir *untracked,
-       const char *dirname, int len, int exclude,
+       const char *dirname, int len, int baselen, int exclude,
        const struct path_simplify *simplify)
  {
        /* The "len-1" is to strip the final '/' */
@@@ -1324,7 -1324,8 +1324,8 @@@
        if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
                return exclude ? path_excluded : path_untracked;
  
-       untracked = lookup_untracked(dir->untracked, untracked, dirname, len);
+       untracked = lookup_untracked(dir->untracked, untracked,
+                                    dirname + baselen, len - baselen);
        return read_directory_recursive(dir, dirname, len,
                                        untracked, 1, simplify);
  }
@@@ -1444,6 -1445,7 +1445,7 @@@ static int get_dtype(struct dirent *de
  static enum path_treatment treat_one_path(struct dir_struct *dir,
                                          struct untracked_cache_dir *untracked,
                                          struct strbuf *path,
+                                         int baselen,
                                          const struct path_simplify *simplify,
                                          int dtype, struct dirent *de)
  {
@@@ -1495,8 -1497,8 +1497,8 @@@
                return path_none;
        case DT_DIR:
                strbuf_addch(path, '/');
-               return treat_directory(dir, untracked, path->buf, path->len, exclude,
-                       simplify);
+               return treat_directory(dir, untracked, path->buf, path->len,
+                                      baselen, exclude, simplify);
        case DT_REG:
        case DT_LNK:
                return exclude ? path_excluded : path_untracked;
@@@ -1557,7 -1559,7 +1559,7 @@@ static enum path_treatment treat_path(s
                return path_none;
  
        dtype = DTYPE(de);
-       return treat_one_path(dir, untracked, path, simplify, dtype, de);
+       return treat_one_path(dir, untracked, path, baselen, simplify, dtype, de);
  }
  
  static void add_untracked(struct untracked_cache_dir *dir, const char *name)
@@@ -1827,7 -1829,7 +1829,7 @@@ static int treat_leading_path(struct di
                        break;
                if (simplify_away(sb.buf, sb.len, simplify))
                        break;
-               if (treat_one_path(dir, NULL, &sb, simplify,
+               if (treat_one_path(dir, NULL, &sb, baselen, simplify,
                                   DT_DIR, NULL) == path_none)
                        break; /* do not recurse into it */
                if (len <= baselen) {
@@@ -1847,7 -1849,7 +1849,7 @@@ static const char *get_ident_string(voi
  
        if (sb.len)
                return sb.buf;
 -      if (uname(&uts))
 +      if (uname(&uts) < 0)
                die_errno(_("failed to get kernel name and information"));
        strbuf_addf(&sb, "Location %s, system %s %s %s", get_git_work_tree(),
                    uts.sysname, uts.release, uts.version);
@@@ -2174,8 -2176,6 +2176,8 @@@ int remove_dir_recursively(struct strbu
        return remove_dir_recurse(path, flag, NULL);
  }
  
 +static GIT_PATH_FUNC(git_path_info_exclude, "info/exclude")
 +
  void setup_standard_excludes(struct dir_struct *dir)
  {
        const char *path;
@@@ -2190,7 -2190,7 +2192,7 @@@
                                         dir->untracked ? &dir->ss_excludes_file : NULL);
  
        /* per repository user preference */
 -      path = git_path("info/exclude");
 +      path = git_path_info_exclude();
        if (!access_or_warn(path, R_OK, 0))
                add_excludes_from_file_1(dir, path,
                                         dir->untracked ? &dir->ss_info_exclude : NULL);
@@@ -2616,23 -2616,67 +2618,67 @@@ done2
        return uc;
  }
  
+ static void invalidate_one_directory(struct untracked_cache *uc,
+                                    struct untracked_cache_dir *ucd)
+ {
+       uc->dir_invalidated++;
+       ucd->valid = 0;
+       ucd->untracked_nr = 0;
+ }
+ 
+ /*
+  * Normally when an entry is added or removed from a directory,
+  * invalidating that directory is enough. No need to touch its
+  * ancestors. When a directory is shown as "foo/bar/" in git-status
+  * however, deleting or adding an entry may have cascading effect.
+  *
+  * Say the "foo/bar/file" has become untracked, we need to tell the
+  * untracked_cache_dir of "foo" that "bar/" is not an untracked
+  * directory any more (because "bar" is managed by foo as an untracked
+  * "file").
+  *
+  * Similarly, if "foo/bar/file" moves from untracked to tracked and it
+  * was the last untracked entry in the entire "foo", we should show
+  * "foo/" instead. Which means we have to invalidate past "bar" up to
+  * "foo".
+  *
+  * This function traverses all directories from root to leaf. If there
+  * is a chance of one of the above cases happening, we invalidate back
+  * to root. Otherwise we just invalidate the leaf. There may be a more
+  * sophisticated way than checking for SHOW_OTHER_DIRECTORIES to
+  * detect these cases and avoid unnecessary invalidation, for example,
+  * checking for the untracked entry named "bar/" in "foo", but for now
+  * stick to something safe and simple.
+  */
+ static int invalidate_one_component(struct untracked_cache *uc,
+                                   struct untracked_cache_dir *dir,
+                                   const char *path, int len)
+ {
+       const char *rest = strchr(path, '/');
+ 
+       if (rest) {
+               int component_len = rest - path;
+               struct untracked_cache_dir *d =
+                       lookup_untracked(uc, dir, path, component_len);
+               int ret =
+                       invalidate_one_component(uc, d, rest + 1,
+                                                len - (component_len + 1));
+               if (ret)
+                       invalidate_one_directory(uc, dir);
+               return ret;
+       }
+ 
+       invalidate_one_directory(uc, dir);
+       return uc->dir_flags & DIR_SHOW_OTHER_DIRECTORIES;
+ }
+ 
  void untracked_cache_invalidate_path(struct index_state *istate,
                                     const char *path)
  {
-       const char *sep;
-       struct untracked_cache_dir *d;
        if (!istate->untracked || !istate->untracked->root)
                return;
-       sep = strrchr(path, '/');
-       if (sep)
-               d = lookup_untracked(istate->untracked,
-                                    istate->untracked->root,
-                                    path, sep - path);
-       else
-               d = istate->untracked->root;
-       istate->untracked->dir_invalidated++;
-       d->valid = 0;
-       d->untracked_nr = 0;
+       invalidate_one_component(istate->untracked, istate->untracked->root,
+                                path, strlen(path));
  }
  
  void untracked_cache_remove_from_index(struct index_state *istate,