Namespace aliases fixed

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

@@ -256,6 +256,9 @@ public class TypeHierarchyResolver {
                 }
 
                 String aliasName = importDirective.getAliasName();
+                if (aliasName == null) {
+                    aliasName = referenceExpression != null ? referenceExpression.getReferencedName() : null;
+                }
                 if (classifierDescriptor != null) {
                     context.getTrace().record(BindingContext.REFERENCE_TARGET, referenceExpression, classifierDescriptor);
 

compiler/frontend/src/org/jetbrains/jet/lang/resolve/scopes/WritableScopeImpl.java

@@ -27,9 +27,13 @@ public class WritableScopeImpl extends WritableScopeWithImports {
 
     @Nullable
     private SetMultimap<String, FunctionDescriptor> functionGroups;
+
     @Nullable
     private Map<String, DeclarationDescriptor> variableClassOrNamespaceDescriptors;
 
+    @Nullable
+    private Map<String, NamespaceDescriptor> namespaceAliases;
+
     @Nullable
     private Map<String, List<DeclarationDescriptor>> labelsToDescriptors;
 
@@ -129,6 +133,14 @@ public class WritableScopeImpl extends WritableScopeWithImports {
         return variableClassOrNamespaceDescriptors;
     }
 
+    @NotNull
+    private Map<String, NamespaceDescriptor> getNamespaceAliases() {
+        if (namespaceAliases == null) {
+            namespaceAliases = Maps.newHashMap();
+        }
+        return namespaceAliases;
+    }
+
     @Override
     public void addVariableDescriptor(@NotNull VariableDescriptor variableDescriptor) {
         Map<String, DeclarationDescriptor> variableClassOrNamespaceDescriptors = getVariableClassOrNamespaceDescriptors();
@@ -203,7 +215,7 @@ public class WritableScopeImpl extends WritableScopeWithImports {
     @Override
     public void addNamespaceAlias(@NotNull String name, @NotNull NamespaceDescriptor namespaceDescriptor) {
         checkForRedeclaration(name, namespaceDescriptor);
-        getVariableClassOrNamespaceDescriptors().put(name, namespaceDescriptor);
+        getNamespaceAliases().put(name, namespaceDescriptor);
         allDescriptors.add(namespaceDescriptor);
     }
 
@@ -258,6 +270,9 @@ public class WritableScopeImpl extends WritableScopeWithImports {
         NamespaceDescriptor declaredNamespace = getDeclaredNamespace(name);
         if (declaredNamespace != null) return declaredNamespace;
 
+        NamespaceDescriptor aliased = getNamespaceAliases().get(name);
+        if (aliased != null) return aliased;
+
         NamespaceDescriptor namespace = getWorkerScope().getNamespace(name);
         if (namespace != null) return namespace;
         return super.getNamespace(name);

idea/testData/checker/ExtensionFunctions.jet

@@ -55,10 +55,10 @@ namespace null_safety {
 
             val command = parse("")
 
-            command<error>.</error>foo
+            command.foo
 
             command.equals(null)
-            command<warning>?.</warning>equals(null)
+            command?.equals(null)
             command.equals1(null)
             command<warning>?.</warning>equals1(null)