Allow ..Nothing to resolve to Nothing (#9746)

enso-org · Apr 22, 2024 · 11dda5b · 11dda5b
1 parent fa6b7f8
commit 11dda5b
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Showing 2 changed files with 20 additions and 2 deletions.
diff --git a/...ne/runtime/src/main/java/org/enso/interpreter/runtime/callable/UnresolvedConstructor.java b/...ne/runtime/src/main/java/org/enso/interpreter/runtime/callable/UnresolvedConstructor.java
@@ -217,7 +217,7 @@ Object instantiateCached(
         @Cached("buildApplication(prototype)") DirectCallNode callNode,
         @Cached("expectedType.getConstructors().get(prototype.getName())") AtomConstructor c) {
       if (c == null) {
-        return null;
+        return checkSingleton(expectedType, unresolved);
       } else {
         return invokeConstructor(c, prototype, unresolved, state, callNode);
       }
@@ -229,7 +229,7 @@ Object instantiateUncached(
         MaterializedFrame frame, State state, Type expectedType, UnresolvedConstructor unresolved) {
       var c = expectedType.getConstructors().get(unresolved.getName());
       if (c == null) {
-        return null;
+        return checkSingleton(expectedType, unresolved);
       }
       var callNode = buildApplication(unresolved);
       return invokeConstructor(c, unresolved.asPrototype(), unresolved, state, callNode);
@@ -249,6 +249,19 @@ private static Object invokeConstructor(
       var r = callNode.call(helper);
       return r;
     }
+
+    private static Object checkSingleton(Type c, UnresolvedConstructor unresolved) {
+      if (!c.isEigenType()) {
+        return null;
+      } else {
+        return equalTypeAndConstructorName(c, unresolved) ? c : null;
+      }
+    }
+
+    @CompilerDirectives.TruffleBoundary
+    private static boolean equalTypeAndConstructorName(Type c, UnresolvedConstructor unresolved) {
+      return c.getName().equals(unresolved.getName());
+    }
   }
 
   @ExportMessage

diff --git a/test/Base_Tests/src/Semantic/Conversion_Spec.enso b/test/Base_Tests/src/Semantic/Conversion_Spec.enso
@@ -507,6 +507,11 @@ add_specs suite_builder =
 
             foo_vec vec . should_equal [3, 4, 5]
 
+        group_builder.specify "Autoscope Nothing" <|
+            accept (n:Nothing) = n
+
+            accept ..Nothing . is_nothing . should_be_true
+
     suite_builder.group "Polyglot Argument" group_builder->
         f1 (x : DateTimeFormatter) = x.to_text
         f2 (x : Text | DateTimeFormatter) = case x of