t0006 & t5000: prepare for 64-bit timestamps

Git's source code refers to timestamps as unsigned longs. On 32-bit
platforms, as well as on Windows, unsigned long is not large enough to
capture dates that are "absurdly far in the future".

It is perfectly valid by the C standard, of course, for the `long` data
type to refer to 32-bit integers. That is why the `time_t` data type
exists: so that it can be 64-bit even if `long` is 32-bit. Git's source
code simply uses an incorrect data type for timestamps, is all.

The earlier quick fix 6b9c38e14cd (t0006: skip "far in the future" test
when unsigned long is not long enough, 2016-07-11) papered over this
issue simply by skipping the respective test cases on platforms where
they would fail due to the data type in use.

This quick fix, however, tests for *long* to be 64-bit or not. What we
need, though, is a test that says whether *whatever data type we use for
timestamps* is 64-bit or not.

The same quick fix was used to handle the similar problem where Git's
source code uses `unsigned long` to represent size, instead of `size_t`,
conflating the two issues.

So let's just add another prerequisite to test specifically whether
timestamps are represented by a 64-bit data type or not. Later, after we
switch to a larger data type, we can flip that prerequisite to test
`time_t` instead of `long`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/t/t5000-tar-tree.sh b/t/t5000-tar-tree.sh
index 886b6953e4..997aa9dea2 100755
--- a/t/t5000-tar-tree.sh
+++ b/t/t5000-tar-tree.sh
@@ -390,7 +390,7 @@ test_expect_success TAR_HUGE,LONG_IS_64BIT 'system tar can read our huge size' '
 	test_cmp expect actual
 '
 
-test_expect_success LONG_IS_64BIT 'set up repository with far-future commit' '
+test_expect_success TIME_IS_64BIT 'set up repository with far-future commit' '
 	rm -f .git/index &&
 	echo content >file &&
 	git add file &&
@@ -398,11 +398,11 @@ test_expect_success LONG_IS_64BIT 'set up repository with far-future commit' '
 		git commit -m "tempori parendum"
 '
 
-test_expect_success LONG_IS_64BIT 'generate tar with future mtime' '
+test_expect_success TIME_IS_64BIT 'generate tar with future mtime' '
 	git archive HEAD >future.tar
 '
 
-test_expect_success TAR_HUGE,LONG_IS_64BIT 'system tar can read our future mtime' '
+test_expect_success TAR_HUGE,TIME_IS_64BIT 'system tar can read our future mtime' '
 	echo 4147 >expect &&
 	tar_info future.tar | cut -d" " -f2 >actual &&
 	test_cmp expect actual