t5004: test ZIP archives with many entries

A ZIP file directory has a 16-bit field for the number of entries it
contains.  There are 64-bit extensions to deal with that.  Demonstrate
that git archive --format=zip currently doesn't use them and instead
overflows the field.

InfoZIP's unzip doesn't care about this field and extracts all files
anyway.  Software that uses the directory for presenting a filesystem
like view quickly -- notably Windows -- depends on it, but doesn't
lend itself to an automatic test case easily.  Use InfoZIP's zipinfo,
which probably isn't available everywhere but at least can provides
*some* way to check this field.

To speed things up a bit create and commit only a subset of the files
and build a fake tree out of duplicates and pass that to git archive.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t5004-archive-corner-cases.sh b/t/t5004-archive-corner-cases.sh
index 654addaae3e7040bcb4ce1014ee327511f73c8e5..c6bd7290a3c5a757351ea1adad24993e808e11cc 100755 (executable)
--- a/t/t5004-archive-corner-cases.sh
+++ b/t/t5004-archive-corner-cases.sh
@@ -115,4 +115,44 @@ test_expect_success 'archive empty subtree by direct pathspec' '
        check_dir extract sub
 '
 
+ZIPINFO=zipinfo
+
+test_lazy_prereq ZIPINFO '
+       n=$("$ZIPINFO" "$TEST_DIRECTORY"/t5004/empty.zip | sed -n "2s/.* //p")
+       test "x$n" = "x0"
+'
+
+test_expect_failure ZIPINFO 'zip archive with many entries' '
+       # add a directory with 256 files
+       mkdir 00 &&
+       for a in 0 1 2 3 4 5 6 7 8 9 a b c d e f
+       do
+               for b in 0 1 2 3 4 5 6 7 8 9 a b c d e f
+               do
+                       : >00/$a$b
+               done
+       done &&
+       git add 00 &&
+       git commit -m "256 files in 1 directory" &&
+
+       # duplicate it to get 65536 files in 256 directories
+       subtree=$(git write-tree --prefix=00/) &&
+       for c in 0 1 2 3 4 5 6 7 8 9 a b c d e f
+       do
+               for d in 0 1 2 3 4 5 6 7 8 9 a b c d e f
+               do
+                       echo "040000 tree $subtree      $c$d"
+               done
+       done >tree &&
+       tree=$(git mktree <tree) &&
+
+       # zip them
+       git archive -o many.zip $tree &&
+
+       # check the number of entries in the ZIP file directory
+       expr 65536 + 256 >expect &&
+       "$ZIPINFO" many.zip | head -2 | sed -n "2s/.* //p" >actual &&
+       test_cmp expect actual
+'
+
 test_done