mktag tests: test hash-object --literally and unreachable fsck

Extend the mktag tests to pass the tag we've created through both
hash-object --literally and fsck.

This checks that fsck itself will not complain about certain invalid
content if a reachable tip isn't involved. Due to how fsck works and
walks the graph the failure will be different if the object is
reachable, so we might succeed before we've created the ref.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t3800-mktag.sh

@@ -16,6 +16,8 @@ check_verify_failure () {
 	message=$2 &&
 	shift 2 &&
 
+	no_strict= &&
+	fsck_obj_ok= &&
 	no_strict= &&
 	while test $# != 0
 	do
@@ -23,6 +25,9 @@ check_verify_failure () {
 		--no-strict)
 			no_strict=yes
 			;;
+		--fsck-obj-ok)
+			fsck_obj_ok=yes
+			;;
 		esac &&
 		shift
 	done &&
@@ -37,6 +42,23 @@ check_verify_failure () {
 			git mktag --no-strict <tag.sig
 		fi
 	'
+
+	test_expect_success "setup: $subject" '
+		# Reset any leftover state from the last $subject
+		rm -rf bad-tag &&
+
+		git init --bare bad-tag &&
+		git -C bad-tag hash-object -t tag -w --stdin --literally <tag.sig
+	'
+
+	test_expect_success "hash-object & fsck unreachable: $subject" '
+		if test -n "$fsck_obj_ok"
+		then
+			git -C bad-tag fsck
+		else
+			test_must_fail git -C bad-tag fsck
+		fi
+	'
 }
 
 test_expect_mktag_success() {
@@ -183,7 +205,8 @@ tagger . <> 0 +0000
 EOF
 
 check_verify_failure 'verify object (hash/type) check -- correct type, nonexisting object' \
-	'^fatal: could not read tagged object'
+	'^fatal: could not read tagged object' \
+	--fsck-obj-ok
 
 cat >tag.sig <<EOF
 object $head
@@ -216,7 +239,8 @@ tagger . <> 0 +0000
 EOF
 
 check_verify_failure 'verify object (hash/type) check -- mismatched type, valid object' \
-	'^fatal: object.*tagged as.*tree.*but is.*commit'
+	'^fatal: object.*tagged as.*tree.*but is.*commit' \
+	--fsck-obj-ok
 
 ############################################################
 #  9.5. verify object (hash/type) check -- replacement
@@ -245,7 +269,8 @@ tagger . <> 0 +0000
 EOF
 
 check_verify_failure 'verify object (hash/type) check -- mismatched type, valid object' \
-	'^fatal: object.*tagged as.*tree.*but is.*blob'
+	'^fatal: object.*tagged as.*tree.*but is.*blob' \
+	--fsck-obj-ok
 
 ############################################################
 # 10. verify tag-name check
@@ -260,7 +285,8 @@ EOF
 
 check_verify_failure 'verify tag-name check' \
 	'^error:.* badTagName:' \
-	--no-strict
+	--no-strict \
+	--fsck-obj-ok
 
 ############################################################
 # 11. tagger line label check #1
@@ -275,7 +301,8 @@ EOF
 
 check_verify_failure '"tagger" line label check #1' \
 	'^error:.* missingTaggerEntry:' \
-	--no-strict
+	--no-strict \
+	--fsck-obj-ok
 
 ############################################################
 # 12. tagger line label check #2
@@ -291,7 +318,8 @@ EOF
 
 check_verify_failure '"tagger" line label check #2' \
 	'^error:.* missingTaggerEntry:' \
-	--no-strict
+	--no-strict \
+	--fsck-obj-ok
 
 ############################################################
 # 13. allow missing tag author name like fsck
@@ -321,7 +349,8 @@ EOF
 
 check_verify_failure 'disallow malformed tagger' \
 	'^error:.* badEmail:' \
-	--no-strict
+	--no-strict \
+	--fsck-obj-ok
 
 ############################################################
 # 15. allow empty tag email
@@ -446,7 +475,8 @@ EOF
 
 check_verify_failure 'detect invalid header entry' \
 	'^error:.* extraHeaderEntry:' \
-	--no-strict
+	--no-strict \
+	--fsck-obj-ok
 
 test_expect_success 'invalid header entry config & fsck' '
 	test_must_fail git mktag <tag.sig &&