cat-file: handle trivial --batch format with --batch-all-objects

The --batch code to print an object assumes we found out the type of
the object from calling oid_object_info_extended(). This is true for
the default format, but even in a custom format, we manually modify
the object_info struct to ask for the type.

This assumption was broken by 845de33a5b (cat-file: avoid noop calls
to sha1_object_info_extended, 2016-05-18). That commit skips the call
to oid_object_info_extended() entirely when --batch-all-objects is in
use, and the custom format does not include any placeholders that
require calling it.

Or when the custom format only include placeholders like %(objectname) or
%(rest), oid_object_info_extended() will not get the type of the object.

This results in an error when we try to confirm that the type didn't
change:

$ git cat-file --batch=batman --batch-all-objects
batman
fatal: object 000023961a changed type!?

and also has other subtle effects (e.g., we'd fail to stream a blob,
since we don't realize it's a blob in the first place).

We can fix this by flipping the order of the setup. The check for "do
we need to get the object info" must come _after_ we've decided
whether we need to look up the type.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: ZheNing Hu <adlternative@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
ZheNing Hu 2021-06-03 16:29:25 +00:00 committed by Junio C Hamano
parent 94f6e3e283
commit e16acc80a7
2 changed files with 29 additions and 6 deletions

View file

@ -512,12 +512,6 @@ static int batch_objects(struct batch_options *opt)
if (opt->cmdmode)
data.split_on_whitespace = 1;
if (opt->all_objects) {
struct object_info empty = OBJECT_INFO_INIT;
if (!memcmp(&data.info, &empty, sizeof(empty)))
data.skip_object_info = 1;
}
/*
* If we are printing out the object, then always fill in the type,
* since we will want to decide whether or not to stream.
@ -525,6 +519,13 @@ static int batch_objects(struct batch_options *opt)
if (opt->print_contents)
data.info.typep = &data.type;
if (opt->all_objects) {
struct object_info empty = OBJECT_INFO_INIT;
if (!memcmp(&data.info, &empty, sizeof(empty)))
data.skip_object_info = 1;
}
if (opt->all_objects) {
struct object_cb_data cb;

View file

@ -586,4 +586,26 @@ test_expect_success 'cat-file --unordered works' '
test_cmp expect actual
'
test_expect_success 'set up object list for --batch-all-objects tests' '
git -C all-two cat-file --batch-all-objects --batch-check="%(objectname)" >objects
'
test_expect_success 'cat-file --batch="%(objectname)" with --batch-all-objects will work' '
git -C all-two cat-file --batch="%(objectname)" <objects >expect &&
git -C all-two cat-file --batch-all-objects --batch="%(objectname)" >actual &&
cmp expect actual
'
test_expect_success 'cat-file --batch="%(rest)" with --batch-all-objects will work' '
git -C all-two cat-file --batch="%(rest)" <objects >expect &&
git -C all-two cat-file --batch-all-objects --batch="%(rest)" >actual &&
cmp expect actual
'
test_expect_success 'cat-file --batch="batman" with --batch-all-objects will work' '
git -C all-two cat-file --batch="batman" <objects >expect &&
git -C all-two cat-file --batch-all-objects --batch="batman" >actual &&
cmp expect actual
'
test_done