[gnumeric] t6504: add ods-strict tests.

[Morten Welinder <mortenw src gnome org>]

commit 323da329ad114bcfd4623f34836b4f8ad9e5f163
Author: Morten Welinder <terra gnome org>
Date:   Sun Sep 4 09:30:38 2022 -0400

    t6504: add ods-strict tests.

 test/t6504-formula.pl | 9 +++++++++
 1 file changed, 9 insertions(+)
---
diff --git a/test/t6504-formula.pl b/test/t6504-formula.pl
index 12468dcad..d6f34c5b3 100755
--- a/test/t6504-formula.pl
+++ b/test/t6504-formula.pl
@@ -22,6 +22,15 @@ if (&subtest ("ods")) {
                     'filter2' => 'std:drop_generator');
 }
 
+if (&subtest ("ods-strict")) {
+    &message ("Check string ods strict-conformance roundtrip.");
+    &test_roundtrip ($file,
+                    'format' => 'Gnumeric_OpenCalc:openoffice',
+                    'ext' => "ods",
+                    'filter1' => 'std:ods_strict',
+                    'filter2' => 'std:drop_generator | std:ods_strict');
+}
+
 if (&subtest ("biff7")) {
     &message ("Check formula xls/BIFF7 roundtrip.");
     &test_roundtrip ($file,