Q="'"
+# Test adding and deleting D/F-conflicting references in a single
+# transaction.
+df_test() {
+ prefix="$1"
+ pack=: symadd=false symdel=false add_del=false addref= delref=
+ shift
+ while test $# -gt 0
+ do
+ case "$1" in
+ --pack)
+ pack="git pack-refs --all"
+ shift
+ ;;
+ --sym-add)
+ # Perform the add via a symbolic reference
+ symadd=true
+ shift
+ ;;
+ --sym-del)
+ # Perform the del via a symbolic reference
+ symdel=true
+ shift
+ ;;
+ --del-add)
+ # Delete first reference then add second
+ add_del=false
+ delref="$prefix/r/$2"
+ addref="$prefix/r/$3"
+ shift 3
+ ;;
+ --add-del)
+ # Add first reference then delete second
+ add_del=true
+ addref="$prefix/r/$2"
+ delref="$prefix/r/$3"
+ shift 3
+ ;;
+ *)
+ echo 1>&2 "Extra args to df_test: $*"
+ return 1
+ ;;
+ esac
+ done
+ git update-ref "$delref" $C &&
+ if $symadd
+ then
+ addname="$prefix/s/symadd" &&
+ git symbolic-ref "$addname" "$addref"
+ else
+ addname="$addref"
+ fi &&
+ if $symdel
+ then
+ delname="$prefix/s/symdel" &&
+ git symbolic-ref "$delname" "$delref"
+ else
+ delname="$delref"
+ fi &&
+ cat >expected-err <<-EOF &&
+ fatal: cannot lock ref $Q$addname$Q: $Q$delref$Q exists; cannot create $Q$addref$Q
+ EOF
+ $pack &&
+ if $add_del
+ then
+ printf "%s\n" "create $addname $D" "delete $delname"
+ else
+ printf "%s\n" "delete $delname" "create $addname $D"
+ fi >commands &&
+ test_must_fail git update-ref --stdin <commands 2>output.err &&
+ test_cmp expected-err output.err &&
+ printf "%s\n" "$C $delref" >expected-refs &&
+ git for-each-ref --format="%(objectname) %(refname)" $prefix/r >actual-refs &&
+ test_cmp expected-refs actual-refs
+}
+
test_expect_success 'setup' '
git commit --allow-empty -m Initial &&
git update-ref --stdin
'
+test_expect_success 'D/F conflict prevents add long + delete short' '
+ df_test refs/df-al-ds --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents add short + delete long' '
+ df_test refs/df-as-dl --add-del foo foo/bar
+'
+
+test_expect_success 'D/F conflict prevents delete long + add short' '
+ df_test refs/df-dl-as --del-add foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents delete short + add long' '
+ df_test refs/df-ds-al --del-add foo foo/bar
+'
+
+test_expect_success 'D/F conflict prevents add long + delete short packed' '
+ df_test refs/df-al-dsp --pack --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents add short + delete long packed' '
+ df_test refs/df-as-dlp --pack --add-del foo foo/bar
+'
+
+test_expect_success 'D/F conflict prevents delete long packed + add short' '
+ df_test refs/df-dlp-as --pack --del-add foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents delete short packed + add long' '
+ df_test refs/df-dsp-al --pack --del-add foo foo/bar
+'
+
+# Try some combinations involving symbolic refs...
+
+test_expect_success 'D/F conflict prevents indirect add long + delete short' '
+ df_test refs/df-ial-ds --sym-add --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents indirect add long + indirect delete short' '
+ df_test refs/df-ial-ids --sym-add --sym-del --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents indirect add short + indirect delete long' '
+ df_test refs/df-ias-idl --sym-add --sym-del --add-del foo foo/bar
+'
+
+test_expect_success 'D/F conflict prevents indirect delete long + indirect add short' '
+ df_test refs/df-idl-ias --sym-add --sym-del --del-add foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents indirect add long + delete short packed' '
+ df_test refs/df-ial-dsp --sym-add --pack --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents indirect add long + indirect delete short packed' '
+ df_test refs/df-ial-idsp --sym-add --sym-del --pack --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents add long + indirect delete short packed' '
+ df_test refs/df-al-idsp --sym-del --pack --add-del foo/bar foo
+'
+
+test_expect_success 'D/F conflict prevents indirect delete long packed + indirect add short' '
+ df_test refs/df-idlp-ias --sym-add --sym-del --pack --del-add foo/bar foo
+'
+
# Test various errors when reading the old values of references...
test_expect_success 'missing old value blocks update' '
test_cmp expected output.err
'
+test_expect_success 'no bogus intermediate values during delete' '
+ prefix=refs/slow-transaction &&
+ # Set up a reference with differing loose and packed versions:
+ git update-ref $prefix/foo $C &&
+ git pack-refs --all &&
+ git update-ref $prefix/foo $D &&
+ git for-each-ref $prefix >unchanged &&
+ # Now try to update the reference, but hold the `packed-refs` lock
+ # for a while to see what happens while the process is blocked:
+ : >.git/packed-refs.lock &&
+ test_when_finished "rm -f .git/packed-refs.lock" &&
+ {
+ # Note: the following command is intentionally run in the
+ # background. We increase the timeout so that `update-ref`
+ # attempts to acquire the `packed-refs` lock for longer than
+ # it takes for us to do the check then delete it:
+ git -c core.packedrefstimeout=3000 update-ref -d $prefix/foo &
+ } &&
+ pid2=$! &&
+ # Give update-ref plenty of time to get to the point where it tries
+ # to lock packed-refs:
+ sleep 1 &&
+ # Make sure that update-ref did not complete despite the lock:
+ kill -0 $pid2 &&
+ # Verify that the reference still has its old value:
+ sha1=$(git rev-parse --verify --quiet $prefix/foo || echo undefined) &&
+ case "$sha1" in
+ $D)
+ # This is what we hope for; it means that nothing
+ # user-visible has changed yet.
+ : ;;
+ undefined)
+ # This is not correct; it means the deletion has happened
+ # already even though update-ref should not have been
+ # able to acquire the lock yet.
+ echo "$prefix/foo deleted prematurely" &&
+ break
+ ;;
+ $C)
+ # This value should never be seen. Probably the loose
+ # reference has been deleted but the packed reference
+ # is still there:
+ echo "$prefix/foo incorrectly observed to be C" &&
+ break
+ ;;
+ *)
+ # WTF?
+ echo "unexpected value observed for $prefix/foo: $sha1" &&
+ break
+ ;;
+ esac >out &&
+ rm -f .git/packed-refs.lock &&
+ wait $pid2 &&
+ test_must_be_empty out &&
+ test_must_fail git rev-parse --verify --quiet $prefix/foo
+'
+
+test_expect_success 'delete fails cleanly if packed-refs file is locked' '
+ prefix=refs/locked-packed-refs &&
+ # Set up a reference with differing loose and packed versions:
+ git update-ref $prefix/foo $C &&
+ git pack-refs --all &&
+ git update-ref $prefix/foo $D &&
+ git for-each-ref $prefix >unchanged &&
+ # Now try to delete it while the `packed-refs` lock is held:
+ : >.git/packed-refs.lock &&
+ test_when_finished "rm -f .git/packed-refs.lock" &&
+ test_must_fail git update-ref -d $prefix/foo >out 2>err &&
+ git for-each-ref $prefix >actual &&
+ test_i18ngrep "Unable to create $Q.*packed-refs.lock$Q: File exists" err &&
+ test_cmp unchanged actual
+'
+
test_done