unpack-trees(): ignore worktree check outside checkout area

verify_absent() and verify_uptodate() are used to ensure worktree
is safe to be updated, then CE_REMOVE or CE_UPDATE will be set.
Finally check_updates() bases on CE_REMOVE, CE_UPDATE and the
recently added CE_WT_REMOVE to update working directory accordingly.

The entries that are checked may eventually be left out of checkout
area (done later in apply_sparse_checkout()). We don't want to update
outside checkout area. This patch teaches Git to assume "good",
skip these checks when it's sure those entries will be outside checkout
area, and clear CE_REMOVE|CE_UPDATE that could be set due to this
assumption.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/unpack-trees.c b/unpack-trees.c
index 2d8ecb73b1d252a692678579c90f1bfee54b24f1..72743b34df0944f94af3280f3071b904bde3bec0 100644 (file)
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -505,6 +505,14 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
                                ret = -1;
                                goto done;
                        }
+                       /*
+                        * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
+                        * area as a result of ce_skip_worktree() shortcuts in
+                        * verify_absent() and verify_uptodate(). Clear them.
+                        */
+                       if (ce_skip_worktree(ce))
+                               ce->ce_flags &= ~(CE_UPDATE | CE_REMOVE);
+
                }
        }
 
@@ -577,6 +585,8 @@ static int verify_uptodate_1(struct cache_entry *ce,
 static int verify_uptodate(struct cache_entry *ce,
                           struct unpack_trees_options *o)
 {
+       if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
+               return 0;
        return verify_uptodate_1(ce, o, ERRORMSG(o, not_uptodate_file));
 }
 
@@ -776,6 +786,8 @@ static int verify_absent_1(struct cache_entry *ce, const char *action,
 static int verify_absent(struct cache_entry *ce, const char *action,
                         struct unpack_trees_options *o)
 {
+       if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
+               return 0;
        return verify_absent_1(ce, action, o, ERRORMSG(o, would_lose_untracked));
 }