clone: die on errors from unpack_trees

When clone is populating the working tree, it ignores the
return status from unpack_trees; this means we may report a
successful clone, even when the checkout fails.

When checkout fails, we may want to leave the $GIT_DIR in
place, as it might be possible to recover the data through
further use of "git checkout" (e.g., if the checkout failed
due to a transient error, disk full, etc). However, we
already die on a number of other checkout-related errors, so
this patch follows that pattern.

In addition to marking a now-passing test, we need to adjust
t5710, which blindly assumed it could make bogus clones of
very deep alternates hierarchies. By using "--bare", we can
avoid it actually touching any objects.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin/clone.c

@@ -579,7 +579,8 @@ static int checkout(void)
 	tree = parse_tree_indirect(sha1);
 	parse_tree(tree);
 	init_tree_desc(&t, tree->buffer, tree->size);
-	unpack_trees(1, &t, &opts);
+	if (unpack_trees(1, &t, &opts) < 0)
+		die(_("unable to checkout working tree"));
 
 	if (write_cache(fd, active_cache, active_nr) ||
 	    commit_locked_index(lock_file))

t/t1060-object-corruption.sh

@@ -89,7 +89,7 @@ test_expect_success 'clone --local detects corruption' '
 	test_must_fail git clone --local bit-error corrupt-checkout
 '
 
-test_expect_failure 'clone --local detects missing objects' '
+test_expect_success 'clone --local detects missing objects' '
 	test_must_fail git clone --local missing missing-checkout
 '
 

t/t5710-info-alternate.sh

@@ -58,7 +58,7 @@ test_expect_success 'creating too deep nesting' \
 git clone -l -s D E &&
 git clone -l -s E F &&
 git clone -l -s F G &&
-git clone -l -s G H'
+git clone --bare -l -s G H'
 
 test_expect_success 'invalidity of deepest repository' \
 'cd H && {