When loading a Skylark list or tuple, preserve the type in the BUILD file.

--
MOS_MIGRATED_REVID=105552023

1 files changed, 6 insertions, 3 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkType.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkType.java
index d2899123c3..f79b12983b 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkType.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkType.java
@@ -754,9 +754,12 @@ public abstract class SkylarkType implements Serializable {
    * Converts object from a Skylark-compatible wrapper type to its original type.
    */
   public static Object convertFromSkylark(Object value) {
-    if (value instanceof SkylarkList) {
-      return new ArrayList<>(((SkylarkList) value).getList());
+    if (value instanceof MutableList) {
+      return new ArrayList<>(((MutableList) value).getList());
+    } else if (value instanceof Tuple) {
+      return ((Tuple) value).getImmutableList();
+    } else {
+      return value;
     }
-    return value;
   }
 }