Added error 'public member should specify type' and quick fix

compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/Errors.java

@@ -123,6 +123,8 @@ public interface Errors {
     
     DiagnosticWithParameterFactory<JetNamedDeclaration, JetClass> NON_FINAL_MEMBER_IN_FINAL_CLASS = DiagnosticWithParameterFactory.create(ERROR, "Non final member in a final class", DiagnosticParameters.CLASS);
 
+    DiagnosticWithParameterFactory<JetNamedDeclaration, JetType> PUBLIC_MEMBER_SHOULD_SPECIFY_TYPE = DiagnosticWithParameterFactory.create(ERROR, "Public member should specify a type", DiagnosticParameters.TYPE);
+
     SimpleDiagnosticFactory PROJECTION_ON_NON_CLASS_TYPE_ARGUMENT = SimpleDiagnosticFactory.create(ERROR, "Projections are not allowed on type arguments of functions and properties"); // TODO : better positioning
     SimpleDiagnosticFactory SUPERTYPE_NOT_INITIALIZED = SimpleDiagnosticFactory.create(ERROR, "This type has a constructor, and thus must be initialized here");
     SimpleDiagnosticFactory SECONDARY_CONSTRUCTOR_BUT_NO_PRIMARY = SimpleDiagnosticFactory.create(ERROR, "A secondary constructor may appear only in a class that has a primary constructor");

compiler/frontend/src/org/jetbrains/jet/lang/resolve/ClassDescriptorResolver.java

@@ -481,17 +481,7 @@ public class ClassDescriptorResolver {
 
         JetType type = getVariableType(scopeWithTypeParameters, property, true);
 
-        boolean hasBody = property.getInitializer() != null;
-        if (!hasBody) {
-            JetPropertyAccessor getter = property.getGetter();
-            if (getter != null && getter.getBodyExpression() != null) {
-                hasBody = true;
-            }
-            JetPropertyAccessor setter = property.getSetter();
-            if (!hasBody && setter != null && setter.getBodyExpression() != null) {
-                hasBody = true;
-            }
-        }
+        boolean hasBody = hasBody(property);
         Modality defaultModality = getDefaultModality(containingDeclaration, hasBody);
         PropertyDescriptor propertyDescriptor = new PropertyDescriptor(
                 containingDeclaration,
@@ -513,6 +503,21 @@ public class ClassDescriptorResolver {
         return propertyDescriptor;
     }
 
+    /*package*/ static boolean hasBody(JetProperty property) {
+        boolean hasBody = property.getInitializer() != null;
+        if (!hasBody) {
+            JetPropertyAccessor getter = property.getGetter();
+            if (getter != null && getter.getBodyExpression() != null) {
+                hasBody = true;
+            }
+            JetPropertyAccessor setter = property.getSetter();
+            if (!hasBody && setter != null && setter.getBodyExpression() != null) {
+                hasBody = true;
+            }
+        }
+        return hasBody;
+    }
+
     @NotNull
     private JetType getVariableType(@NotNull final JetScope scope, @NotNull final JetProperty property, boolean allowDeferred) {
         // TODO : receiver?

compiler/frontend/src/org/jetbrains/jet/lang/resolve/DeclarationsChecker.java

@@ -137,6 +137,29 @@ public class DeclarationsChecker {
         checkPropertyAbstractness(property, propertyDescriptor, classDescriptor);
         checkPropertyInitializer(property, propertyDescriptor, classDescriptor);
         checkAccessors(property, propertyDescriptor);
+        checkDeclaredTypeInPublicMember(property, propertyDescriptor);
+    }
+
+    private void checkDeclaredTypeInPublicMember(JetNamedDeclaration member, CallableMemberDescriptor memberDescriptor) {
+        PsiElement nameIdentifier = member.getNameIdentifier();
+        boolean hasDeferredType;
+        if (member instanceof JetProperty) {
+            hasDeferredType = ((JetProperty) member).getPropertyTypeRef() == null && ClassDescriptorResolver.hasBody((JetProperty) member);
+        }
+        else {
+            assert member instanceof JetFunction;
+            JetFunction function = (JetFunction) member;
+            hasDeferredType = function.getReturnTypeRef() == null && function.getBodyExpression() != null && !function.hasBlockBody();
+        }
+        if ((memberDescriptor.getVisibility() == Visibility.PUBLIC || memberDescriptor.getVisibility() == Visibility.PROTECTED) &&
+            hasDeferredType && nameIdentifier != null) {
+
+            JetType returnType = memberDescriptor.getReturnType();
+            if (returnType instanceof DeferredType) {
+                returnType = ((DeferredType) returnType).getActualType();
+            }
+            context.getTrace().report(PUBLIC_MEMBER_SHOULD_SPECIFY_TYPE.on(member, nameIdentifier, returnType));
+        }
     }
 
     private void checkPropertyAbstractness(JetProperty property, PropertyDescriptor propertyDescriptor, ClassDescriptor classDescriptor) {
@@ -232,6 +255,7 @@ public class DeclarationsChecker {
         JetModifierList modifierList = function.getModifierList();
         ASTNode abstractNode = modifierList != null ? modifierList.getModifierNode(JetTokens.ABSTRACT_KEYWORD) : null;
         boolean hasAbstractModifier = abstractNode != null;
+        checkDeclaredTypeInPublicMember(function, functionDescriptor);
         if (containingDescriptor instanceof ClassDescriptor) {
             ClassDescriptor classDescriptor = (ClassDescriptor) containingDescriptor;
             boolean inTrait = classDescriptor.getKind() == ClassKind.TRAIT;