restore: invalidate cache-tree when removing entries with --staged

When "git restore --staged <path>" removes a path that's in the index, it marks the entry with CE_REMOVE, but we don't do anything to invalidate the cache-tree. In the non-staged case, we end up in checkout_worktree(), which calls remove_marked_cache_entries(). That actually drops the entries from the index, as well as invalidating the cache-tree and untracked-cache. But with --staged, we never call checkout_worktree(), and the CE_REMOVE entries remain. Interestingly, they are dropped when we write out the index, but that means the resulting index is inconsistent: its cache-tree will not match the actual entries, and running "git commit" immediately after will create the wrong tree. We can solve this by calling remove_marked_cache_entries() ourselves before writing out the index. Note that we can't just hoist it out of checkout_worktree(); that function needs to iterate over the CE_REMOVE entries (to drop their matching worktree files) before removing them. One curiosity about the test: without this patch, it actually triggers a BUG() when running git-restore: BUG: cache-tree.c:810: new1 with flags 0x4420000 should not be in cache-tree But in the original problem report, which used a similar recipe, git-restore actually creates the bogus index (and the commit is created with the wrong tree). I'm not sure why the test here behaves differently than my out-of-suite reproduction, but what's here should catch either symptom (and the fix corrects both cases). Reported-by: Torsten Krah <krah.tm@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Jan 8, 2020 at 06:43 UTC e701bab3e95f7029e59717eab610a544821b2213

2 files changed +19

builtin/checkout.c

@@ -521,6 +521,8 @@ static int checkout_paths(const struct checkout_opts *opts,

521 /* Now we are committed to check them out */

522 if (opts->checkout_worktree)

523 errs |= checkout_worktree(opts);

524 + else

525 + remove_marked_cache_entries(&the_index, 1);

526

527 /*

528 * Allow updating the index when checking out from the index.

t/t2070-restore.sh

+17

@@ -95,4 +95,21 @@ test_expect_success 'restore --ignore-unmerged ignores unmerged entries' '

95 )

96 '

98 +test_expect_success 'restore --staged invalidates cache tree for deletions' '

99 + test_when_finished git reset --hard &&

100 + >new1 &&

101 + >new2 &&

102 + git add new1 new2 &&

103 +

104 + # It is important to commit and then reset here, so that the index

105 + # contains a valid cache-tree for the "both" tree.

106 + git commit -m both &&

107 + git reset --soft HEAD^ &&

108 +

109 + git restore --staged new1 &&

110 + git commit -m "just new2" &&

111 + git rev-parse HEAD:new2 &&

112 + test_must_fail git rev-parse HEAD:new1

113 +'

114 +

115 test_done