Merge branch 'ks/tree-diff-walk'

* ks/tree-diff-walk:
tree-walk: finally switch over tree descriptors to contain a pre-parsed entry
revision: convert to using diff_tree_sha1()
line-log: convert to using diff_tree_sha1()
tree-diff: convert diff_root_tree_sha1() to just call diff_tree_sha1 with old=NULL
tree-diff: allow diff_tree_sha1 to accept NULL sha1

diff --combined revision.c
index f40ccf14269a3325f4f3069ce931bb73e1d1f27e,7f61ecde8c05885490520ebea0671b8f01f03288..61be08754af91a32f9c7729f2e5223c592faf451
--- 1/revision.c
--- 2/revision.c
+++ b/revision.c
@@@ -16,7 -16,6 +16,7 @@@
  #include "line-log.h"
  #include "mailmap.h"
  #include "commit-slab.h"
 +#include "dir.h"
  
  volatile show_early_output_fn_t show_early_output;
  
@@@ -497,24 -496,14 +497,14 @@@ static int rev_compare_tree(struct rev_
  static int rev_same_tree_as_empty(struct rev_info *revs, struct commit *commit)
  {
        int retval;
-       void *tree;
-       unsigned long size;
-       struct tree_desc empty, real;
        struct tree *t1 = commit->tree;
  
        if (!t1)
                return 0;
  
-       tree = read_object_with_reference(t1->object.sha1, tree_type, &size, NULL);
-       if (!tree)
-               return 0;
-       init_tree_desc(&real, tree, size);
-       init_tree_desc(&empty, "", 0);
- 
        tree_difference = REV_TREE_SAME;
        DIFF_OPT_CLR(&revs->pruning, HAS_CHANGES);
-       retval = diff_tree(&empty, &real, "", &revs->pruning);
-       free(tree);
+       retval = diff_tree_sha1(NULL, t1->object.sha1, "", &revs->pruning);
  
        return retval >= 0 && (tree_difference == REV_TREE_SAME);
  }
@@@ -1401,7 -1390,7 +1391,7 @@@ static void prepare_show_merge(struct r
                const struct cache_entry *ce = active_cache[i];
                if (!ce_stage(ce))
                        continue;
 -              if (ce_path_match(ce, &revs->prune_data)) {
 +              if (ce_path_match(ce, &revs->prune_data, NULL)) {
                        prune_num++;
                        prune = xrealloc(prune, sizeof(*prune) * prune_num);
                        prune[prune_num-2] = ce->name;