Eek, fix for (apparently!) long standing gather read count bug

ink-engine-runtime/Story.cs

@@ -761,7 +761,8 @@ void VisitChangedContainersDueToDivert()
             if (currentChildOfContainer == null) return;
 
             Container currentContainerAncestor = currentChildOfContainer.parent as Container;
-			while (currentContainerAncestor && !_prevContainers.Contains(currentContainerAncestor)) {
+
+            while (currentContainerAncestor && (!_prevContainers.Contains(currentContainerAncestor) || currentContainerAncestor.countingAtStartOnly)) {
 
                 // Check whether this ancestor container is being entered at the start,
                 // by checking whether the child object is the first.

tests/Tests.cs

@@ -3518,6 +3518,76 @@ public void TestUsingFunctionAndIncrementTogether()
             // Ensure it just compiles
             CompileStringWithoutRuntime(storyStr);
         }
+
+        // Fix for rogue "can't use as sub-expression" bug
+        [Test()]
+        public void TestKnotStitchGatherCounts()
+        {
+            var storyStr =
+        @"
+VAR knotCount = 0
+VAR stitchCount = 0
+
+-> gather_count_test ->
+
+~ knotCount = 0
+-> knot_count_test ->
+
+~ knotCount = 0
+-> knot_count_test ->
+
+-> stitch_count_test ->
+
+== gather_count_test ==
+VAR gatherCount = 0
+- (loop)
+~ gatherCount++
+{gatherCount} {loop}
+{gatherCount<3:->loop}
+->->
+
+== knot_count_test ==
+~ knotCount++
+{knotCount} {knot_count_test}
+{knotCount<3:->knot_count_test}
+->->
+
+
+== stitch_count_test ==
+~ stitchCount = 0
+-> stitch ->
+~ stitchCount = 0
+-> stitch ->
+->->
+
+= stitch
+~ stitchCount++
+{stitchCount} {stitch}
+{stitchCount<3:->stitch}
+->->
+";
+
+            // Ensure it just compiles
+            var story = CompileString(storyStr);
+
+            Assert.AreEqual(
+@"1 1
+2 2
+3 3
+1 1
+2 1
+3 1
+1 2
+2 2
+3 2
+1 1
+2 1
+3 1
+1 2
+2 2
+3 2
+", story.ContinueMaximally());
+        }
 
 
         // Helper compile function