Fixes checking for emptiness of subsets when master set is empty

Fixes bug 596671.

diff --git a/gee/treeset.vala b/gee/treeset.vala
index b0672d1..fda7146 100644 (file)
--- a/gee/treeset.vala
+++ b/gee/treeset.vala
@@ -791,9 +791,9 @@ public class Gee.TreeSet<G> : AbstractSet<G>, SortedSet<G> {
                public bool empty_subset () {
                        switch (type) {
                        case RangeType.HEAD:
-                               return !in_range (set._first.key);
+                               return set._first == null || !in_range (set._first.key);
                        case RangeType.TAIL:
-                               return !in_range (set._last.key);
+                               return set._last == null || !in_range (set._last.key);
                        case RangeType.EMPTY:
                                return true;
                        case RangeType.BOUNDED:

diff --git a/tests/testsortedset.vala b/tests/testsortedset.vala
index a8e9f33..c13d9c2 100644 (file)
--- a/tests/testsortedset.vala
+++ b/tests/testsortedset.vala
@@ -428,6 +428,9 @@ public abstract class SortedSetTests : SetTests {
                }
 
                public void test_size () {
+                       assert (subset.is_empty);
+                       assert (subset.size == 0);
+
                        assert (master.add ("one"));
                        assert (master.add ("two"));
                        assert (master.add ("three"));