[PATCH v3 6/6] Make sure that index-pack --strict checks tag objects

[Johannes Schindelin <johannes.schindelin@gmx.de>]

One of the most important use cases for the strict tag object checking
is when transfer.fsckobjects is set to true to catch invalid objects
early on. This new regression test essentially tests the same code path
by directly calling 'index-pack --strict' on a pack containing an
tag object without a 'tagger' line.

Technically, this test is not enough: it only exercises a code path that
*warns*, not one that *fails*. The reason is that it would be exquisitely
convoluted to test that: not only hash-object, but also pack-index
actually *parse* tag objects when encountering them. Therefore we would
have to actively *break* pack-index in order to test this. Or rewrite
both hash-object and pack-index in shell script. Ain't gonna happen.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5302-pack-index.sh | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/t/t5302-pack-index.sh b/t/t5302-pack-index.sh
index 4bbb718..4d033df 100755
--- a/t/t5302-pack-index.sh
+++ b/t/t5302-pack-index.sh
@@ -243,4 +243,23 @@ test_expect_success 'running index-pack in the object store' '
     test -f .git/objects/pack/pack-${pack1}.idx
 '
 
+test_expect_success 'index-pack --strict warns upon missing tagger in tag' '
+    sha=$(git rev-parse HEAD) &&
+    cat >wrong-tag <<EOF &&
+object $sha
+type commit
+tag guten tag
+
+This is an invalid tag.
+EOF
+
+    tag=$(git hash-object -t tag -w --stdin <wrong-tag) &&
+    pack1=$(echo $tag $sha | git pack-objects tag-test) &&
+    echo remove tag object &&
+    thirtyeight=${tag#??} &&
+    rm -f .git/objects/${tag%$thirtyeight}/$thirtyeight &&
+    git index-pack --strict tag-test-${pack1}.pack 2> err &&
+    grep "^error:.* expected .tagger. line" err
+'
+
 test_done
-- 
2.0.0.rc3.9669.g840d1f9