Introduced JetStandardClasses.UNIT_ALIAS constant, got rid of hard-coding it in all code except for tests.

compiler/frontend/src/org/jetbrains/jet/lang/psi/JetPsiUtil.java

@@ -25,6 +25,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.resolve.FqName;
 import org.jetbrains.jet.lang.resolve.ImportPath;
+import org.jetbrains.jet.lang.types.lang.JetStandardClasses;
 import org.jetbrains.jet.lexer.JetTokens;
 
 import java.util.Collection;
@@ -307,7 +308,7 @@ public class JetPsiUtil {
             return false;
         }
 
-        return "Unit".equals(typeReference.getText());
+        return JetStandardClasses.UNIT_ALIAS.equals(typeReference.getText());
     }
 
     public static boolean isSafeCall(@NotNull Call call) {

compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/BasicExpressionTypingVisitor.java

@@ -746,7 +746,7 @@ public class BasicExpressionTypingVisitor extends ExpressionTypingVisitor {
         JetType result;
         if (operationType == JetTokens.PLUSPLUS || operationType == JetTokens.MINUSMINUS) {
             if (JetTypeChecker.INSTANCE.isSubtypeOf(returnType, JetStandardClasses.getUnitType())) {
-                result = ErrorUtils.createErrorType("Unit");
+                result = ErrorUtils.createErrorType(JetStandardClasses.UNIT_ALIAS);
                 context.trace.report(INC_DEC_SHOULD_NOT_RETURN_UNIT.on(operationSign));
             }
             else {

compiler/frontend/src/org/jetbrains/jet/lang/types/lang/JetStandardClasses.java

@@ -258,12 +258,14 @@ public class JetStandardClasses {
     @NotNull
     public static final JetScope STANDARD_CLASSES;
 
+    public static final String UNIT_ALIAS = "Unit";
+
     static {
         WritableScope writableScope = new WritableScopeImpl(JetScope.EMPTY, STANDARD_CLASSES_NAMESPACE, RedeclarationHandler.DO_NOTHING).setDebugName("JetStandardClasses.STANDARD_CLASSES");
         writableScope.changeLockLevel(WritableScope.LockLevel.BOTH);
 
         STANDARD_CLASSES = writableScope;
-        writableScope.addClassifierAlias("Unit", getTuple(0));
+        writableScope.addClassifierAlias(UNIT_ALIAS, getTuple(0));
 
         Field[] declaredFields = JetStandardClasses.class.getDeclaredFields();
         for (Field field : declaredFields) {

compiler/frontend/src/org/jetbrains/jet/resolve/DescriptorRenderer.java

@@ -118,7 +118,7 @@ public class DescriptorRenderer implements Renderer<DeclarationDescriptor> {
             return escape("[NULL]");
         }
         else if (JetStandardClasses.isUnit(type)) {
-            return escape("Unit" + (type.isNullable() ? "?" : ""));
+            return escape(JetStandardClasses.UNIT_ALIAS + (type.isNullable() ? "?" : ""));
         }
         else if (JetStandardClasses.isTupleType(type)) {
             return escape(renderTupleType(type, shortNamesOnly));

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

@@ -87,7 +87,7 @@ public class StandardLibraryReferenceResolver extends AbstractProjectComponent {
             assert tuple0 != null;
             scope = new WritableScopeImpl(scope, jetNamespace, RedeclarationHandler.THROW_EXCEPTION).setDebugName("Builtin classes scope #2");
             scope.changeLockLevel(WritableScope.LockLevel.BOTH);
-            scope.addClassifierAlias("Unit", tuple0);
+            scope.addClassifierAlias(JetStandardClasses.UNIT_ALIAS, tuple0);
             jetNamespace.setMemberScope(scope);
 
             TopDownAnalyzer.processStandardLibraryNamespace(myProject, context, scope, jetNamespace, getJetFiles("jet"));
@@ -136,7 +136,8 @@ public class StandardLibraryReferenceResolver extends AbstractProjectComponent {
             }
             String renderedOriginal = DescriptorRenderer.TEXT.render(originalDescriptor);
             for (DeclarationDescriptor member : memberScope.getAllDescriptors()) {
-                if (renderedOriginal.equals(DescriptorRenderer.TEXT.render(member).replace(TUPLE0_FQ_NAME.getFqName(), "Unit"))) {
+                if (renderedOriginal.equals(DescriptorRenderer.TEXT.render(member).replace(TUPLE0_FQ_NAME.getFqName(),
+                                                                                           JetStandardClasses.UNIT_ALIAS))) {
                     return member;
                 }
             }

j2k/src/org/jetbrains/jet/j2k/visitors/TypeVisitor.java

@@ -23,6 +23,7 @@ import org.jetbrains.jet.j2k.Converter;
 import org.jetbrains.jet.j2k.J2KConverterFlags;
 import org.jetbrains.jet.j2k.ast.*;
 import org.jetbrains.jet.j2k.util.AstUtil;
+import org.jetbrains.jet.lang.types.lang.JetStandardClasses;
 
 import java.util.LinkedList;
 import java.util.List;
@@ -61,7 +62,7 @@ public class TypeVisitor extends PsiTypeVisitor<Type> implements J2KVisitor {
         final IdentifierImpl identifier = new IdentifierImpl(name);
 
         if (name.equals("void")) {
-            myResult = new PrimitiveType(new IdentifierImpl("Unit"));
+            myResult = new PrimitiveType(new IdentifierImpl(JetStandardClasses.UNIT_ALIAS));
         }
         else if (Node.PRIMITIVE_TYPES.contains(name)) {
             myResult = new PrimitiveType(new IdentifierImpl(AstUtil.upperFirstCharacter(name)));