Giving up on fixing root problem, adding hack

CTrando · CTrando · commit 699a6b0bfc71 · 2019-08-30T17:41:30.000-07:00
diff --git a/src/Analysis/Ast/Impl/Analyzer/Handlers/SequenceExpressionHandler.cs b/src/Analysis/Ast/Impl/Analyzer/Handlers/SequenceExpressionHandler.cs
@@ -66,9 +66,13 @@ private static void Assign(SequenceExpression seq, ValueEnumerator valueEnum, Ex
                         eval.DeclareVariable(nex.Name, valueEnum.Next, VariableSource.Declaration, nex);
                         break;
                     // Nested sequence expression in sequence, Tuple[Tuple[int, str], int], List[Tuple[int], str]
-                    case SequenceExpression se when valueEnum.Peek is IPythonCollection:
-                        var pc = valueEnum.Next as IPythonCollection;
-                        Assign(se, pc, eval);
+                    // TODO: Because of bug with how collection types are constructed, they don't make nested collection types
+                    // into instances, meaning we have to create it here
+                    case SequenceExpression se when valueEnum.Peek is IPythonCollection || valueEnum.Peek is IPythonCollectionType:
+                        var collection = valueEnum.Next;
+                        var pc = collection as IPythonCollection;
+                        var pct = collection as IPythonCollectionType;
+                        Assign(se, pc ?? pct.CreateInstance(), eval);
                         break;
                     case SequenceExpression se:
                         Assign(se, valueEnum, eval);
diff --git a/src/Analysis/Ast/Impl/Utilities/ValueEnumerator.cs b/src/Analysis/Ast/Impl/Utilities/ValueEnumerator.cs
@@ -6,7 +6,7 @@
 namespace Microsoft.Python.Analysis.Utilities {
     internal sealed class ValueEnumerator {
         private readonly IMember _value;
-        private readonly IMember _unknown;
+        private readonly IPythonType _unknown;
         private readonly IMember[] _values;
         private int _index;
 
@@ -15,7 +15,7 @@ internal sealed class ValueEnumerator {
         /// </summary>
         /// <param name="value">Collection to iterate over</param>
         /// <param name="unknown">Default type when we cannot find type from collection</param>
-        public ValueEnumerator(IMember value, IMember unknown) {
+        public ValueEnumerator(IMember value, IPythonType unknown) {
             _value = value;
             _unknown = unknown;
             switch (value) {
@@ -43,12 +43,12 @@ public IMember Peek {
                 if (_values.Length > 0) {
                     return _index < _values.Length ? _values[_index] : _values[_values.Length - 1];
                 } else {
-                    return Filler;
+                    return Filler.CreateInstance();
                 }
             }
         }
 
-        private IMember Filler {
+        private IPythonType Filler {
             get {
                 switch (_value?.GetPythonType()) {
                     case ITypingListType tlt:
