sometimes descriptor has more than one declaration

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

@@ -16,6 +16,7 @@
 
 package org.jetbrains.jet.lang.resolve;
 
+import com.google.common.collect.Lists;
 import com.intellij.psi.PsiElement;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -31,6 +32,8 @@ import org.jetbrains.jet.lang.types.lang.JetStandardClasses;
 import org.jetbrains.jet.util.slicedmap.ReadOnlySlice;
 import org.jetbrains.jet.util.slicedmap.Slices;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Set;
 
 /**
@@ -83,6 +86,27 @@ public class BindingContextUtils {
         return null;
     }
 
+    @NotNull
+    public static List<PsiElement> resolveToDeclarationPsiElements(@NotNull BindingContext bindingContext, @Nullable JetReferenceExpression referenceExpression) {
+        DeclarationDescriptor declarationDescriptor = bindingContext.get(BindingContext.REFERENCE_TARGET, referenceExpression);
+        if (declarationDescriptor == null) {
+            return Lists.newArrayList(bindingContext.get(BindingContext.LABEL_TARGET, referenceExpression));
+        }
+
+        List<PsiElement> elements = descriptorToDeclarations(bindingContext, declarationDescriptor);
+        if (elements.size() > 0) {
+            return elements;
+        }
+
+        // TODO: Need to have a valid stubs for standard classes
+        if (referenceExpression != null && JetStandardClasses.getAllStandardClasses().contains(declarationDescriptor)) {
+            return Lists.<PsiElement>newArrayList(referenceExpression.getContainingFile());
+        }
+
+        return Lists.newArrayList();
+    }
+
+
     @Nullable
     public static VariableDescriptor extractVariableDescriptorIfAny(@NotNull BindingContext bindingContext, @Nullable JetElement element, boolean onlyReference) {
         DeclarationDescriptor descriptor = null;
@@ -131,6 +155,21 @@ public class BindingContextUtils {
         }
     }
 
+    @NotNull
+    public static List<PsiElement> descriptorToDeclarations(@NotNull BindingContext context, @NotNull DeclarationDescriptor descriptor) {
+        if (descriptor instanceof CallableMemberDescriptor) {
+            return callableDescriptorToDeclarations(context, (CallableMemberDescriptor) descriptor);
+        }
+        else {
+            PsiElement psiElement = descriptorToDeclaration(context, descriptor);
+            if (psiElement != null) {
+                return Lists.newArrayList(psiElement);
+            } else {
+                return Lists.newArrayList();
+            }
+        }
+    }
+
     @Nullable
     public static PsiElement callableDescriptorToDeclaration(@NotNull BindingContext context, @NotNull CallableMemberDescriptor callable) {
         if (callable.getKind() != CallableMemberDescriptor.Kind.DECLARATION) {
@@ -148,6 +187,19 @@ public class BindingContextUtils {
         return doGetDescriptorToDeclaration(context, callable.getOriginal());
     }
 
+    private static List<PsiElement> callableDescriptorToDeclarations(@NotNull BindingContext context, @NotNull CallableMemberDescriptor callable) {
+        if (callable.getKind() != CallableMemberDescriptor.Kind.DECLARATION) {
+            List<PsiElement> r = new ArrayList<PsiElement>();
+            Set<? extends CallableMemberDescriptor> overridenDescriptors = callable.getOverriddenDescriptors();
+            for (CallableMemberDescriptor overriden : overridenDescriptors) {
+                r.addAll(callableDescriptorToDeclarations(context, overriden));
+            }
+            return r;
+        }
+        PsiElement psiElement = doGetDescriptorToDeclaration(context, callable);
+        return psiElement != null ? Lists.newArrayList(psiElement) : Lists.<PsiElement>newArrayList();
+    }
+
     @Nullable
     public static PsiElement classDescriptorToDeclaration(@NotNull BindingContext context, @NotNull ClassDescriptor clazz) {
         return doGetDescriptorToDeclaration(context, clazz);

idea/src/org/jetbrains/jet/plugin/references/JetPsiReference.java

@@ -33,6 +33,7 @@ import org.jetbrains.jet.plugin.project.WholeProjectAnalyzerFacade;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.List;
 
 import static org.jetbrains.jet.lang.resolve.BindingContext.AMBIGUOUS_REFERENCE_TARGET;
 
@@ -102,9 +103,12 @@ public abstract class JetPsiReference implements PsiPolyVariantReference {
     protected PsiElement doResolve() {
         JetFile file = (JetFile) getElement().getContainingFile();
         BindingContext bindingContext = WholeProjectAnalyzerFacade.analyzeProjectWithCacheOnAFile(file).getBindingContext();
-        PsiElement psiElement = BindingContextUtils.resolveToDeclarationPsiElement(bindingContext, myExpression);
+        List<PsiElement> psiElement = BindingContextUtils.resolveToDeclarationPsiElements(bindingContext, myExpression);
-        if (psiElement != null) {
+        if (psiElement.size() == 1) {
-            return psiElement;
+            return psiElement.iterator().next();
+        }
+        if (psiElement.size() > 1) {
+            return null;
         }
         Collection<? extends DeclarationDescriptor> declarationDescriptors = bindingContext.get(AMBIGUOUS_REFERENCE_TARGET, myExpression);
         if (declarationDescriptors != null) return null;
@@ -123,13 +127,17 @@ public abstract class JetPsiReference implements PsiPolyVariantReference {
         ArrayList<ResolveResult> results = new ArrayList<ResolveResult>(declarationDescriptors.size());
         
         for (DeclarationDescriptor descriptor : declarationDescriptors) {
-            PsiElement element = BindingContextUtils.descriptorToDeclaration(bindingContext, descriptor);
+            List<PsiElement> elements = BindingContextUtils.descriptorToDeclarations(bindingContext, descriptor);
-            if (element == null) {
+            if (elements.isEmpty()) {
                 // TODO: Need a better resolution for Intrinsic function (KT-975)
-                element = file;
+                results.add(new PsiElementResolveResult(file, true));
+            }
+            else {
+                for (PsiElement element : elements) {
+                    results.add(new PsiElementResolveResult(element, true));
+                }
             }
 
-            results.add(new PsiElementResolveResult(element, true));
         }
 
         return results.toArray(new ResolveResult[results.size()]);