Added diagnostic error when in function declaration name was omitted

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -333,6 +333,8 @@ public interface Errors {
     DiagnosticFactory1<JetFunction, SimpleFunctionDescriptor> NON_MEMBER_FUNCTION_NO_BODY =
             DiagnosticFactory1.create(ERROR, DECLARATION_SIGNATURE);
 
+    DiagnosticFactory0<JetFunction> FUNCTION_DECLARATION_WITH_NO_NAME = DiagnosticFactory0.create(ERROR, DECLARATION_SIGNATURE);
+
     DiagnosticFactory0<JetParameter> VALUE_PARAMETER_WITH_NO_TYPE_ANNOTATION = DiagnosticFactory0.create(ERROR);
 
     DiagnosticFactory0<JetNamedFunction> NO_TAIL_CALLS_FOUND = DiagnosticFactory0.create(WARNING, DECLARATION_SIGNATURE);

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/PositioningStrategies.kt

@@ -32,7 +32,9 @@ public object PositioningStrategies {
     private open class DeclarationHeader<T : JetDeclaration> : PositioningStrategy<T>() {
         override fun isValid(element: T): Boolean {
             if (element is JetNamedDeclaration &&
-                (element !is JetObjectDeclaration && element !is JetSecondaryConstructor)
+                element !is JetObjectDeclaration &&
+                element !is JetSecondaryConstructor &&
+                element !is JetNamedFunction
             ) {
                 if (element.getNameIdentifier() == null) {
                     return false
@@ -103,6 +105,9 @@ public object PositioningStrategies {
                 }
                 return markElement(nameIdentifier)
             }
+            if (element is JetNamedFunction) {
+                return DECLARATION_SIGNATURE.mark(element)
+            }
             return DEFAULT.mark(element)
         }
     }

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -224,6 +224,7 @@ public class DefaultErrorMessages {
         MAP.put(FINAL_FUNCTION_WITH_NO_BODY, "Function ''{0}'' without body cannot be final", NAME);
 
         MAP.put(NON_MEMBER_FUNCTION_NO_BODY, "Function ''{0}'' must have a body", NAME);
+        MAP.put(FUNCTION_DECLARATION_WITH_NO_NAME, "Function declaration must have a name");
         MAP.put(NON_FINAL_MEMBER_IN_FINAL_CLASS, "\"open\" has no effect in a final class");
 
         MAP.put(PUBLIC_MEMBER_SHOULD_SPECIFY_TYPE, "Public or protected member should have specified type");

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

@@ -237,7 +237,19 @@ public class DescriptorResolver {
             @NotNull DataFlowInfo dataFlowInfo
     ) {
         return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
-                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace));
+                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace), false);
+    }
+
+    @NotNull
+    public SimpleFunctionDescriptor resolveAnonymousFunctionDescriptor(
+            @NotNull DeclarationDescriptor containingDescriptor,
+            @NotNull JetScope scope,
+            @NotNull JetNamedFunction function,
+            @NotNull BindingTrace trace,
+            @NotNull DataFlowInfo dataFlowInfo
+    ) {
+        return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
+                                         annotationResolver.resolveAnnotationsWithArguments(scope, function.getModifierList(), trace), true);
     }
 
     @NotNull
@@ -249,7 +261,7 @@ public class DescriptorResolver {
             @NotNull DataFlowInfo dataFlowInfo
     ) {
        return resolveFunctionDescriptor(containingDescriptor, scope, function, trace, dataFlowInfo,
-                                        annotationResolver.resolveAnnotationsWithoutArguments(scope, function.getModifierList(), trace));
+                                        annotationResolver.resolveAnnotationsWithoutArguments(scope, function.getModifierList(), trace), false);
     }
 
     @NotNull
@@ -259,12 +271,17 @@ public class DescriptorResolver {
             @NotNull final JetNamedFunction function,
             @NotNull final BindingTrace trace,
             @NotNull final DataFlowInfo dataFlowInfo,
-            @NotNull Annotations annotations
+            @NotNull Annotations annotations,
+            boolean nameCanBeOmitted
     ) {
+        if (!nameCanBeOmitted && function.getName() == null) {
+            trace.report(FUNCTION_DECLARATION_WITH_NO_NAME.on(function));
+        }
+
         final SimpleFunctionDescriptorImpl functionDescriptor = SimpleFunctionDescriptorImpl.create(
                 containingDescriptor,
                 annotations,
-                JetPsiUtil.safeName(function.getName()),
+                function.getNameAsSafeName(),
                 CallableMemberDescriptor.Kind.DECLARATION,
                 toSourceElement(function)
         );