index-pack: --fsck-objects to take an optional argument for fsck msgs

git-index-pack has a --strict option that can take an optional argument
to provide a list of fsck issues to change their severity.
--fsck-objects does not have such a utility, which would be useful if
one would like to be more lenient or strict on data integrity in a
repository.

Like --strict, allow --fsck-objects to also take a list of fsck msgs to
change the severity.

Remove the "For internal use only" note for --fsck-objects, and document
the option. This won't often be used by the normal end user, but it
turns out it is useful for Git forges like GitLab.

Reviewed-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: John Cai <johncai86@gmail.com>

Documentation/git-index-pack.txt

@@ -96,8 +96,14 @@ default and "Indexing objects" when `--stdin` is specified.
 --check-self-contained-and-connected::
 	Die if the pack contains broken links. For internal use only.
 
---fsck-objects::
-	For internal use only.
+--fsck-objects[=<msg-ids>=<severity>...]::
+	Check for broken objects, but unlike `--strict`, don't broken links.
+	An optional comma-separated list of `<msg-id>=<severity>` is passed to
+	change the severity of some possible issues, e.g.,
+	`--fsck-objects="missingEmail=ignore,badTagName=ignore"`. See the entry
+	for the `fsck.<msg-id>` configuration options in `linkgit:git-fsck[1]`
+	for more information on the possible values of `<msg-id>` and
+	`<severity>`.
 +
 Die if the pack contains broken objects. If the pack contains a tree
 pointing to a .gitmodules blob that does not exist, prints the hash of

builtin/index-pack.c

@@ -24,7 +24,7 @@
 #include "setup.h"
 
 static const char index_pack_usage[] =
-"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--[no-]rev-index] [--verify] [--strict[=<msg-id>=<severity>...]] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
+"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--[no-]rev-index] [--verify] [--strict[=<msg-id>=<severity>...]] [--fsck-objects[=<msg-id>=<severity>...]] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
 
 struct object_entry {
 	struct pack_idx_entry idx;
@@ -1785,8 +1785,9 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 			} else if (!strcmp(arg, "--check-self-contained-and-connected")) {
 				strict = 1;
 				check_self_contained_and_connected = 1;
-			} else if (!strcmp(arg, "--fsck-objects")) {
+			} else if (skip_to_optional_arg(arg, "--fsck-objects", &arg)) {
 				do_fsck_object = 1;
+				fsck_set_msg_types(&fsck_options, arg);
 			} else if (!strcmp(arg, "--verify")) {
 				verify = 1;
 			} else if (!strcmp(arg, "--verify-stat")) {

t/t5300-pack-object.sh

@@ -441,8 +441,7 @@ test_expect_success 'index-pack with --strict' '
 	)
 '
 
-test_expect_success 'index-pack with --strict downgrading fsck msgs' '
-	test_when_finished rm -rf strict &&
+test_expect_success 'setup for --strict and --fsck-objects downgrading fsck msgs' '
 	git init strict &&
 	(
 		cd strict &&
@@ -457,12 +456,32 @@ test_expect_success 'index-pack with --strict downgrading fsck msgs' '
 
 		EOF
 		git hash-object --literally -t commit -w --stdin <commit >commit_list &&
-		PACK=$(git pack-objects test <commit_list) &&
-		test_must_fail git index-pack --strict "test-$PACK.pack" &&
-		git index-pack --strict="missingEmail=ignore" "test-$PACK.pack"
+		git pack-objects test <commit_list >pack-name
 	)
 '
 
+test_with_bad_commit () {
+	must_fail_arg="$1" &&
+	must_pass_arg="$2" &&
+	(
+		cd strict &&
+		test_expect_fail git index-pack "$must_fail_arg" "test-$(cat pack-name).pack"
+		git index-pack "$must_pass_arg" "test-$(cat pack-name).pack"
+	)
+}
+
+test_expect_success 'index-pack with --strict downgrading fsck msgs' '
+	test_with_bad_commit --strict --strict="missingEmail=ignore"
+'
+
+test_expect_success 'index-pack with --fsck-objects downgrading fsck msgs' '
+	test_with_bad_commit --fsck-objects --fsck-objects="missingEmail=ignore"
+'
+
+test_expect_success 'cleanup for --strict and --fsck-objects downgrading fsck msgs' '
+	rm -rf strict
+'
+
 test_expect_success 'honor pack.packSizeLimit' '
 	git config pack.packSizeLimit 3m &&
 	packname_10=$(git pack-objects test-10 <obj-list) &&