KT-362 Don't allow autocasts on vals that are not internal

compiler/frontend/src/org/jetbrains/jet/lang/descriptors/ClassDescriptor.java

@@ -14,7 +14,7 @@ import java.util.Set;
 /**
  * @author abreslav
  */
-public interface ClassDescriptor extends ClassifierDescriptor {
+public interface ClassDescriptor extends ClassifierDescriptor, MemberDescriptor {
 
     @NotNull
     JetScope getMemberScope(List<TypeProjection> typeArguments);
@@ -53,9 +53,11 @@ public interface ClassDescriptor extends ClassifierDescriptor {
     @NotNull
     ClassKind getKind();
 
+    @Override
     @NotNull
     Modality getModality();
-    
+
+    @Override
     @NotNull
     Visibility getVisibility();
 

compiler/frontend/src/org/jetbrains/jet/lang/descriptors/DeclarationDescriptorWithVisibility.java

@@ -0,0 +1,11 @@
+package org.jetbrains.jet.lang.descriptors;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author abreslav
+ */
+public interface DeclarationDescriptorWithVisibility extends DeclarationDescriptor {
+    @NotNull
+    Visibility getVisibility();
+}

compiler/frontend/src/org/jetbrains/jet/lang/descriptors/MemberDescriptor.java

@@ -5,10 +5,11 @@ import org.jetbrains.annotations.NotNull;
 /**
  * @author abreslav
  */
-public interface MemberDescriptor {
+public interface MemberDescriptor extends DeclarationDescriptor, DeclarationDescriptorWithVisibility {
     @NotNull
     Modality getModality();
-    
+
+    @Override
     @NotNull
     Visibility getVisibility();
 }

compiler/frontend/src/org/jetbrains/jet/lang/descriptors/Visibility.java

@@ -1,5 +1,7 @@
 package org.jetbrains.jet.lang.descriptors;
 
+import java.util.EnumSet;
+
 /**
  * @author svtk
  */
@@ -11,6 +13,8 @@ public enum Visibility {
     INTERNAL_PROTECTED(false),
     LOCAL(false);
 
+    public static final EnumSet<Visibility> INTERNAL_VISIBILITIES = EnumSet.of(PRIVATE, INTERNAL, INTERNAL_PROTECTED, LOCAL);
+    
     private final boolean isAPI;
 
     private Visibility(boolean visibleOutside) {

compiler/frontend/src/org/jetbrains/jet/lang/resolve/calls/autocasts/DataFlowValueFactory.java

@@ -46,29 +46,6 @@ public class DataFlowValueFactory {
         return new DataFlowValue(variableDescriptor, type, isStableVariable(variableDescriptor), getImmanentNullability(type));
     }
 
-//    private Object getId(@NotNull JetExpression expression, @NotNull BindingContext bindingContext) {
-//        if (expression instanceof JetThisExpression) {
-//            JetThisExpression thisExpression = (JetThisExpression) expression;
-//            DeclarationDescriptor declarationDescriptor = bindingContext.get(REFERENCE_TARGET, thisExpression.getThisReference());
-//            if (declarationDescriptor instanceof CallableDescriptor) {
-//                return ((CallableDescriptor) declarationDescriptor).getReceiverParameter();
-//            }
-//            if (declarationDescriptor instanceof ClassDescriptor) {
-//                return ((ClassDescriptor) declarationDescriptor).getImplicitReceiver();
-//            }
-////            throw new AssertionError("No resolution data for expression " + expression.getText());
-//        }
-//        else if (expression instanceof JetReferenceExpression) {
-//            JetReferenceExpression referenceExpression = (JetReferenceExpression) expression;
-//            DeclarationDescriptor declarationDescriptor = bindingContext.get(REFERENCE_TARGET, referenceExpression);
-//            if (declarationDescriptor != null) {
-//                return declarationDescriptor;
-//            }
-////            throw new AssertionError("No resolution data for expression " + expression.getText() + DiagnosticUtils.atLocation(expression));
-//        }
-//        return expression;
-//    }
-
     private Nullability getImmanentNullability(JetType type) {
         return type.isNullable() ? Nullability.UNKNOWN : Nullability.NOT_NULL;
     }
@@ -142,18 +119,38 @@ public class DataFlowValueFactory {
         if (variableDescriptor.isVar()) return false;
         if (variableDescriptor instanceof PropertyDescriptor) {
             PropertyDescriptor propertyDescriptor = (PropertyDescriptor) variableDescriptor;
-            DeclarationDescriptor containingDeclaration = propertyDescriptor.getContainingDeclaration();
-            if (containingDeclaration instanceof ClassDescriptor) {
-                ClassDescriptor classDescriptor = (ClassDescriptor) containingDeclaration;
-                if (classDescriptor.getModality().isOverridable() && propertyDescriptor.getModality().isOverridable()) return false;
-            }
-            else {
-                assert !propertyDescriptor.getModality().isOverridable() : "Property outside a class must not be overridable";
-            }
-            // TODO: check that it's internal
-            PropertyGetterDescriptor getter = propertyDescriptor.getGetter();
-            if (getter != null && !getter.isDefault()) return false;
+            if (!isInternal(propertyDescriptor)) return false;
+            if (!isFinal(propertyDescriptor)) return false;
+            if (!hasDefaultGetter(propertyDescriptor)) return false;
         }
         return true;
     }
+
+    private static boolean isFinal(PropertyDescriptor propertyDescriptor) {
+        DeclarationDescriptor containingDeclaration = propertyDescriptor.getContainingDeclaration();
+        if (containingDeclaration instanceof ClassDescriptor) {
+            ClassDescriptor classDescriptor = (ClassDescriptor) containingDeclaration;
+            if (classDescriptor.getModality().isOverridable() && propertyDescriptor.getModality().isOverridable()) return false;
+        }
+        else {
+            assert !propertyDescriptor.getModality().isOverridable() : "Property outside a class must not be overridable";
+        }
+        return true;
+    }
+
+    private static boolean isInternal(@NotNull DeclarationDescriptorWithVisibility descriptor) {
+        if (Visibility.INTERNAL_VISIBILITIES.contains(descriptor.getVisibility())) return true;
+
+        DeclarationDescriptor containingDeclaration = descriptor.getContainingDeclaration();
+        if (!(containingDeclaration instanceof DeclarationDescriptorWithVisibility)) {
+            return false;
+        }
+
+        return isInternal((DeclarationDescriptorWithVisibility) containingDeclaration);
+    }
+
+    private static boolean hasDefaultGetter(PropertyDescriptor propertyDescriptor) {
+        PropertyGetterDescriptor getter = propertyDescriptor.getGetter();
+        return getter == null || getter.isDefault();
+    }
 }

idea/testData/checkerWithErrorTypes/quick/nullabilityAndAutoCasts/kt362.jet

@@ -0,0 +1,30 @@
+// KT-362 Don't allow autocasts on vals that are not internal
+namespace example;
+
+namespace test {
+    public class Public() {
+        public val public : Int? = 1;
+        protected val protected : Int? = 1;
+        internal protected val i_protected : Int? = 1;
+        val internal : Int? = 1
+    }
+    internal class Internal() {
+        public val public : Int? = 1;
+        protected val protected : Int? = 1;
+        internal protected val i_protected : Int? = 1;
+        val internal : Int? = 1
+    }
+}
+
+fun test() {
+  val p = test.Public()
+  if (p.public is Int) <!AUTOCAST_IMPOSSIBLE!>p.public<!> + 1
+  if (p.protected is Int) <!AUTOCAST_IMPOSSIBLE!>p.protected<!> + 1
+  if (p.i_protected is Int) p.i_protected + 1
+  if (p.internal is Int) p.internal + 1
+  val i = test.Public()
+  if (i.public is Int) <!AUTOCAST_IMPOSSIBLE!>i.public<!> + 1
+  if (i.protected is Int) <!AUTOCAST_IMPOSSIBLE!>i.protected<!> + 1
+  if (i.i_protected is Int) i.i_protected + 1
+  if (i.internal is Int) i.internal + 1
+}