icalcomponent_vanew - document passing NULL as final argumentissue585

fixes: #585

3 files changed, 5 insertions, 11 deletions

diff --git a/src/libical/icalcomponent.c b/src/libical/icalcomponent.c
index 04f61449..c89f4cfd 100644
--- a/src/libical/icalcomponent.c
+++ b/src/libical/icalcomponent.c
@@ -115,6 +115,8 @@ icalcomponent *icalcomponent_new(icalcomponent_kind kind)
 
 icalcomponent *icalcomponent_vanew(icalcomponent_kind kind, ...)
 {
+    /* See https://github.com/libical/libical/issues/585. Caller must pass NULL as final argument */
+
     va_list args;
 
     icalcomponent *impl = icalcomponent_new_impl(kind);
diff --git a/src/libical/icalcomponent.h b/src/libical/icalcomponent.h
index 2b00fee7..e0501bca 100644
--- a/src/libical/icalcomponent.h
+++ b/src/libical/icalcomponent.h
@@ -52,6 +52,8 @@ LIBICAL_ICAL_EXPORT icalcomponent *icalcomponent_new_clone(icalcomponent *compon
 LIBICAL_ICAL_EXPORT icalcomponent *icalcomponent_new_from_string(const char *str);
 
 /** @brief Constructor
+ *
+ * Make sure to pass NULL (not 0) as the final argument!
  */
 LIBICAL_ICAL_EXPORT icalcomponent *icalcomponent_vanew(icalcomponent_kind kind, ...);
 
diff --git a/src/test/regression.c b/src/test/regression.c
index 130cdbfa..82b52915 100644
--- a/src/test/regression.c
+++ b/src/test/regression.c
@@ -4992,24 +4992,14 @@ void test_icalcomponent_with_lastmodified(void)
 
     icalcomponent *comp;
     struct icaltimetype lm = icaltime_from_timet_with_zone(1661280150, 0, NULL);
-#if 1
     comp = icalcomponent_vanew(ICAL_VCALENDAR_COMPONENT,
                                icalproperty_new_version("2.0"),
                                icalproperty_new_prodid("PROD-ABC"),
                                icalproperty_new_uid("1234abcd"),
                                icalproperty_new_lastmodified(lm),
                                icalproperty_new_name("name1"),
-                               0);
+                               NULL); /* NOT 0! */
     icalcomponent_free(comp);
-#else
-    comp = icalcomponent_new(ICAL_VCALENDAR_COMPONENT);
-    icalcomponent_add_property(comp, icalproperty_new_version("2.0"));
-    icalcomponent_add_property(comp, icalproperty_new_prodid("PROD-ABC"));
-    icalcomponent_add_property(comp, icalproperty_new_uid("1234abcd"));
-    icalcomponent_add_property(comp, icalproperty_new_lastmodified(lm));
-    icalcomponent_add_property(comp, icalproperty_new_name("name1"));
-    icalcomponent_free(comp);
-#endif
 }
 
 int main(int argc, char *argv[])