Introduce interface method: VariableDescriptor.isConst

And several default implementations
Also take it into account in renderer

compiler/backend/src/org/jetbrains/kotlin/codegen/AccessorForPropertyDescriptor.java

@@ -57,7 +57,7 @@ public class AccessorForPropertyDescriptor extends PropertyDescriptorImpl implem
     ) {
         super(containingDeclaration, null, Annotations.EMPTY, Modality.FINAL, Visibilities.LOCAL,
               original.isVar(), Name.identifier("access$" + getIndexedAccessorSuffix(original, index)),
-              Kind.DECLARATION, SourceElement.NO_SOURCE, false);
+              Kind.DECLARATION, SourceElement.NO_SOURCE, /* lateInit = */ false, /* isConst = */ false);
 
         this.calleeDescriptor = original;
         this.accessorIndex = index;

compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaSyntheticPropertiesScope.kt

@@ -261,7 +261,8 @@ class JavaSyntheticPropertiesScope(storageManager: StorageManager) : JetScopeImp
             kind: CallableMemberDescriptor.Kind,
             source: SourceElement
     ) : SyntheticJavaPropertyDescriptor, PropertyDescriptorImpl(containingDeclaration, original, annotations,
-                                                                modality, visibility, isVar, name, kind, source, false) {
+                                                                modality, visibility, isVar, name, kind, source,
+                                                                /* lateInit = */ false, /* isConst = */ false) {
 
         override var getMethod: FunctionDescriptor by Delegates.notNull()
             private set

compiler/frontend/src/org/jetbrains/kotlin/resolve/DescriptorResolver.java

@@ -645,7 +645,8 @@ public class DescriptorResolver {
                     JetPsiUtil.safeName(variable.getName()),
                     CallableMemberDescriptor.Kind.DECLARATION,
                     toSourceElement(variable),
-                    false
+                    /* lateInit = */ false,
+                    /* isConst = */ false
             );
             // For a local variable the type must not be deferred
             type = getVariableType(propertyDescriptor, scope, variable, dataFlowInfo, false, trace);
@@ -743,7 +744,8 @@ public class DescriptorResolver {
                 JetPsiUtil.safeName(property.getName()),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 toSourceElement(property),
-                modifierList != null && modifierList.hasModifier(JetTokens.LATE_INIT_KEYWORD)
+                modifierList != null && modifierList.hasModifier(JetTokens.LATE_INIT_KEYWORD),
+                modifierList != null && modifierList.hasModifier(JetTokens.CONST_KEYWORD)
         );
         wrapper.setProperty(propertyDescriptor);
 
@@ -1114,7 +1116,8 @@ public class DescriptorResolver {
                 name,
                 CallableMemberDescriptor.Kind.DECLARATION,
                 toSourceElement(parameter),
-                false
+                /* lateInit = */ false,
+                /* isConst = */ false
         );
         propertyWrapper.setProperty(propertyDescriptor);
         propertyDescriptor.setType(type, Collections.<TypeParameterDescriptor>emptyList(),

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tasks/dynamicCalls.kt

@@ -95,7 +95,8 @@ object DynamicCallableDescriptors {
                 name,
                 CallableMemberDescriptor.Kind.DECLARATION,
                 SourceElement.NO_SOURCE,
-                false
+                /* lateInit = */ false,
+                /* isConst = */ false
         )
         propertyDescriptor.setType(
                 DynamicType,

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/util/FakeCallableDescriptorForObject.kt

@@ -61,4 +61,6 @@ public class FakeCallableDescriptorForObject(
     override fun getCompileTimeInitializer() = null
 
     override fun getSource(): SourceElement = classDescriptor.getSource()
+
+    override fun isConst(): Boolean = false
 }

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptClassMemberScope.kt

@@ -93,7 +93,8 @@ public class LazyScriptClassMemberScope protected constructor(
                 Name.identifier(ScriptDescriptor.LAST_EXPRESSION_VALUE_FIELD_NAME),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 SourceElement.NO_SOURCE,
-                false
+                /* lateInit = */ false,
+                /* isConst = */ false
         )
 
         val returnType = scriptDescriptor.getScriptCodeDescriptor().getReturnType()
@@ -134,7 +135,8 @@ public class LazyScriptClassMemberScope protected constructor(
                 parameter.getName(),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 SourceElement.NO_SOURCE,
-                false
+                /* lateInit = */ false,
+                /* isConst = */ false
         )
         propertyDescriptor.setType(
                 parameter.getType(),

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/descriptors/JavaPropertyDescriptor.java

@@ -36,7 +36,8 @@ public class JavaPropertyDescriptor extends PropertyDescriptorImpl implements Ja
             @NotNull SourceElement source,
             @Nullable PropertyDescriptor original
     ) {
-        super(containingDeclaration, original, annotations, Modality.FINAL, visibility, isVar, name, Kind.DECLARATION, source, false);
+        super(containingDeclaration, original, annotations, Modality.FINAL, visibility, isVar, name, Kind.DECLARATION, source,
+              /* lateInit = */ false, /* isConst = */ false);
     }
 
     @Override

core/descriptors/src/org/jetbrains/kotlin/descriptors/VariableDescriptor.java

@@ -37,4 +37,10 @@ public interface VariableDescriptor extends CallableDescriptor {
 
     @Nullable
     ConstantValue<?> getCompileTimeInitializer();
+
+    /**
+     * @return true if iff original declaration has appropriate flags and type, e.g. `const` modifier in Kotlin.
+     * It completely does not means that if isConst then `getCompileTimeInitializer` is not null
+     */
+    boolean isConst();
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/PropertyDescriptorImpl.java

@@ -40,6 +40,7 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
     private final PropertyDescriptor original;
     private final Kind kind;
     private final boolean lateInit;
+    private final boolean isConst;
 
     private ReceiverParameterDescriptor dispatchReceiverParameter;
     private ReceiverParameterDescriptor extensionReceiverParameter;
@@ -58,7 +59,8 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
             @NotNull Name name,
             @NotNull Kind kind,
             @NotNull SourceElement source,
-            boolean lateInit
+            boolean lateInit,
+            boolean isConst
     ) {
         super(containingDeclaration, annotations, name, null, isVar, source);
         this.modality = modality;
@@ -66,6 +68,7 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
         this.original = original == null ? this : original;
         this.kind = kind;
         this.lateInit = lateInit;
+        this.isConst = isConst;
     }
 
     @NotNull
@@ -78,10 +81,11 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
             @NotNull Name name,
             @NotNull Kind kind,
             @NotNull SourceElement source,
-            boolean lateInit
+            boolean lateInit,
+            boolean isConst
     ) {
         return new PropertyDescriptorImpl(containingDeclaration, null, annotations,
-                                          modality, visibility, isVar, name, kind, source, lateInit);
+                                          modality, visibility, isVar, name, kind, source, lateInit, isConst);
     }
 
     public void setType(
@@ -179,6 +183,11 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
         return lateInit;
     }
 
+    @Override
+    public boolean isConst() {
+        return isConst;
+    }
+
     @Override
     @NotNull
     public List<PropertyAccessorDescriptor> getAccessors() {
@@ -300,7 +309,7 @@ public class PropertyDescriptorImpl extends VariableDescriptorWithInitializerImp
     ) {
         return new PropertyDescriptorImpl(newOwner, original,
                                           getAnnotations(), newModality, newVisibility,
-                                          isVar(), getName(), kind, SourceElement.NO_SOURCE, isLateInit());
+                                          isVar(), getName(), kind, SourceElement.NO_SOURCE, isLateInit(), isConst());
     }
 
     @NotNull

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/VariableDescriptorImpl.java

@@ -102,4 +102,9 @@ public abstract class VariableDescriptorImpl extends DeclarationDescriptorNonRoo
     public JetType getReturnType() {
         return getType();
     }
+
+    @Override
+    public boolean isConst() {
+        return false;
+    }
 }

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRendererImpl.kt

@@ -707,6 +707,11 @@ internal class DescriptorRendererImpl(
         if (!startFromName) {
             renderAnnotations(property, builder)
             renderVisibility(property.getVisibility(), builder)
+
+            if (property.isConst) {
+                builder.append("const ")
+            }
+
             renderModalityForCallable(property, builder)
             renderOverride(property, builder)
             renderLateInit(property, builder)

core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java

@@ -401,7 +401,8 @@ public class ErrorUtils {
                 Name.special("<ERROR PROPERTY>"),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 SourceElement.NO_SOURCE,
-                /*lateInit =*/ false
+                /* lateInit = */ false,
+                /* isConst = */ false
         );
         descriptor.setType(ERROR_PROPERTY_TYPE,
                            Collections.<TypeParameterDescriptor>emptyList(),

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/descriptors/DeserializedPropertyDescriptor.kt

@@ -42,7 +42,7 @@ public class DeserializedPropertyDescriptor(
         lateInit: Boolean
 ) : DeserializedCallableMemberDescriptor,
     PropertyDescriptorImpl(containingDeclaration, original, annotations,
-                           modality, visibility, isVar, name, kind, SourceElement.NO_SOURCE, lateInit) {
+                           modality, visibility, isVar, name, kind, SourceElement.NO_SOURCE, lateInit, false) {
 
     override fun createSubstitutedCopy(
             newOwner: DeclarationDescriptor,
@@ -52,6 +52,6 @@ public class DeserializedPropertyDescriptor(
             kind: Kind
     ): PropertyDescriptorImpl {
         return DeserializedPropertyDescriptor(
-                newOwner, original, annotations, newModality, newVisibility, isVar, name, kind, proto, nameResolver, isLateInit)
+                newOwner, original, annotations, newModality, newVisibility, isVar, name, kind, proto, nameResolver, isLateInit, false)
     }
 }