Fix sorting indices of a list with children

src/main/java/ch/njol/skript/expressions/ExprIndices.java

@@ -30,6 +30,7 @@
 import ch.njol.skript.lang.util.SimpleExpression;
 import ch.njol.skript.util.LiteralUtils;
 import ch.njol.util.Kleenean;
+import ch.njol.util.Pair;
 import org.bukkit.event.Event;
 import org.eclipse.jdt.annotation.Nullable;
 
@@ -101,8 +102,14 @@ protected String[] get(Event e) {
 		if (sort) {
 			int direction = descending ? -1 : 1;
 			return variable.entrySet().stream()
+				.map((entry) -> new Pair<>(
+					entry.getKey(),
+					entry.getValue() instanceof Map<?,?>
+						? ((Map<?,?>) entry.getValue()).get(null)
+						: entry.getValue()
+				))
 				.sorted((a, b) -> ExprSortedList.compare(a.getValue(), b.getValue()) * direction)
-				.map(Entry::getKey)
+				.map(Pair::getKey)
 				.toArray(String[]::new);
 		}
 

src/test/skript/tests/regressions/6881-sorted indices with children.sk

@@ -0,0 +1,15 @@
+test "sorted indices with children":
+	set {_test::1} to 111
+	set {_test::2} to 555
+	set {_test::3} to 444
+	set {_test::1::a} to 2
+	set {_test::2::b} to 3
+	set {_test::3::c} to 6
+	set {_test::3::a::foo} to "i"
+	set {_test::3::b::bar} to "love"
+	set {_test::3::c::baz} to "skript"
+	set {_indices::*} to (sorted indices of {_test::*} in ascending order)
+
+	assert {_indices::*} is ("1", "3", "2") with "sorted indices on list with children threw or was incorrect"
+	assert {_test::*} is (111, 555, 444) with "modified children wrongly"
+	assert {_test::3::*} is 6 with "modified children wrongly"