'this' is resolved to the corresponding declaration in labeled function literals

idea/src/org/jetbrains/jet/lang/cfg/JetControlFlowProcessor.java

@@ -72,10 +72,12 @@ public class JetControlFlowProcessor {
     }
 
     @Nullable
-    private JetElement resolveLabel(@NotNull String labelName, @NotNull JetSimpleNameExpression labelExpression) {
+    private JetElement resolveLabel(@NotNull String labelName, @NotNull JetSimpleNameExpression labelExpression, boolean reportUnresolved) {
         Stack<JetElement> stack = labeledElements.get(labelName);
         if (stack == null || stack.isEmpty()) {
-            trace.getErrorHandler().unresolvedReference(labelExpression);
+            if (reportUnresolved) {
+                trace.getErrorHandler().unresolvedReference(labelExpression);
+            }
             return null;
         }
         else if (stack.size() > 1) {
@@ -119,6 +121,12 @@ public class JetControlFlowProcessor {
 
         @Override
         public void visitThisExpression(JetThisExpression expression) {
+            JetSimpleNameExpression targetLabel = expression.getTargetLabel();
+            if (targetLabel != null) {
+                String labelName = expression.getLabelName();
+                assert labelName != null;
+                resolveLabel(labelName, targetLabel, false);
+            }
             builder.read(expression);
         }
 
@@ -416,7 +424,7 @@ public class JetControlFlowProcessor {
             if (labelName != null) {
                 JetSimpleNameExpression targetLabel = expression.getTargetLabel();
                 assert targetLabel != null;
-                loop = resolveLabel(labelName, targetLabel);
+                loop = resolveLabel(labelName, targetLabel, true);
                 if (!isLoop(loop)) {
                     trace.getErrorHandler().genericError(expression.getNode(), "The label '" + targetLabel.getText() + "' does not denote a loop");
                     loop = null;
@@ -448,7 +456,7 @@ public class JetControlFlowProcessor {
             if (labelElement != null) {
                 String labelName = expression.getLabelName();
                 assert labelName != null;
-                subroutine = resolveLabel(labelName, labelElement);
+                subroutine = resolveLabel(labelName, labelElement, true);
             }
             else {
                 subroutine = builder.getCurrentSubroutine();

idea/src/org/jetbrains/jet/lang/descriptors/ConstructorDescriptorImpl.java

@@ -27,7 +27,7 @@ public class ConstructorDescriptorImpl extends FunctionDescriptorImpl implements
 
     @Override
     @Deprecated
-    public FunctionDescriptor initialize(@Nullable JetType receiverType, @NotNull List<TypeParameterDescriptor> typeParameters, @NotNull List<ValueParameterDescriptor> unsubstitutedValueParameters, @NotNull JetType unsubstitutedReturnType) {
+    public FunctionDescriptorImpl initialize(@Nullable JetType receiverType, @NotNull List<TypeParameterDescriptor> typeParameters, @NotNull List<ValueParameterDescriptor> unsubstitutedValueParameters, @Nullable JetType unsubstitutedReturnType) {
         assert receiverType == null;
         return super.initialize(null, typeParameters, unsubstitutedValueParameters, unsubstitutedReturnType);
     }

idea/src/org/jetbrains/jet/lang/descriptors/FunctionDescriptorImpl.java

@@ -40,7 +40,7 @@ public class FunctionDescriptorImpl extends DeclarationDescriptorImpl implements
         this.original = original;
     }
 
-    public FunctionDescriptor initialize(
+    public FunctionDescriptorImpl initialize(
             @Nullable JetType receiverType,
             @NotNull List<TypeParameterDescriptor> typeParameters,
             @NotNull List<ValueParameterDescriptor> unsubstitutedValueParameters,
@@ -52,6 +52,10 @@ public class FunctionDescriptorImpl extends DeclarationDescriptorImpl implements
         return this;
     }
 
+    public void setReturnType(JetType unsubstitutedReturnType) {
+        this.unsubstitutedReturnType = unsubstitutedReturnType;
+    }
+
     @Override
     public JetType getReceiverType() {
         return receiverType;

idea/src/org/jetbrains/jet/lang/resolve/ClassDescriptorResolver.java

@@ -248,7 +248,7 @@ public class ClassDescriptorResolver {
     }
 
     @NotNull
-    private MutableValueParameterDescriptor resolveValueParameterDescriptor(DeclarationDescriptor declarationDescriptor, JetParameter valueParameter, int index, JetType type) {
+    public MutableValueParameterDescriptor resolveValueParameterDescriptor(DeclarationDescriptor declarationDescriptor, JetParameter valueParameter, int index, JetType type) {
         MutableValueParameterDescriptor valueParameterDescriptor = new ValueParameterDescriptorImpl(
             declarationDescriptor,
             index,
@@ -343,7 +343,7 @@ public class ClassDescriptorResolver {
 
     @NotNull
     public VariableDescriptor resolveLocalVariableDescriptor(DeclarationDescriptor containingDeclaration, WritableScope scope, JetProperty property) {
-        JetType type = getType(scope, property, false); // For a local variable the type must not be deferred
+        JetType type = getVariableType(scope, property, false); // For a local variable the type must not be deferred
 
         VariableDescriptorImpl variableDescriptor = new LocalVariableDescriptor(
                 containingDeclaration,
@@ -380,7 +380,7 @@ public class ClassDescriptorResolver {
         JetModifierList modifierList = property.getModifierList();
         boolean isVar = property.isVar();
 
-        JetType type = getType(scopeWithTypeParameters, property, true);
+        JetType type = getVariableType(scopeWithTypeParameters, property, true);
 
         PropertyDescriptor propertyDescriptor = new PropertyDescriptor(
                 containingDeclaration,
@@ -402,7 +402,7 @@ public class ClassDescriptorResolver {
     }
 
     @NotNull
-    private JetType getType(@NotNull final JetScope scope, @NotNull JetProperty property, boolean allowDeferred) {
+    private JetType getVariableType(@NotNull final JetScope scope, @NotNull JetProperty property, boolean allowDeferred) {
         // TODO : receiver?
         JetTypeReference propertyTypeRef = property.getPropertyTypeRef();
 

idea/src/org/jetbrains/jet/lang/resolve/JetScope.java

@@ -3,7 +3,7 @@ package org.jetbrains.jet.lang.resolve;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.descriptors.*;
-import org.jetbrains.jet.lang.types.*;
+import org.jetbrains.jet.lang.types.JetType;
 
 import java.util.Collection;
 

idea/src/org/jetbrains/jet/lang/types/JetTypeInferrer.java

@@ -1,6 +1,7 @@
 package org.jetbrains.jet.lang.types;
 
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.intellij.lang.ASTNode;
@@ -735,10 +736,6 @@ public class JetTypeInferrer {
                 return;
             }
 
-            FunctionDescriptorImpl functionDescriptor = new FunctionDescriptorImpl(scope.getContainingDeclaration(), Collections.<Annotation>emptyList(), "<anonymous>");
-
-            JetTypeReference returnTypeRef = expression.getReturnTypeRef();
-
             JetTypeReference receiverTypeRef = expression.getReceiverTypeRef();
             final JetType receiverType;
             if (receiverTypeRef != null) {
@@ -747,31 +744,44 @@ public class JetTypeInferrer {
                 receiverType = scope.getThisType();
             }
 
-            List<JetElement> body = expression.getBody();
+            FunctionDescriptorImpl functionDescriptor = new FunctionDescriptorImpl(
-            final Map<String, VariableDescriptor> parameterDescriptors = new HashMap<String, VariableDescriptor>();
+                    scope.getContainingDeclaration(), Collections.<Annotation>emptyList(), "<anonymous>");
+
             List<JetType> parameterTypes = new ArrayList<JetType>();
-            for (JetParameter parameter : expression.getParameters()) {
+            List<ValueParameterDescriptor> valueParameterDescriptors = Lists.newArrayList();
+            List<JetParameter> parameters = expression.getParameters();
+            for (int i = 0, parametersSize = parameters.size(); i < parametersSize; i++) {
+                JetParameter parameter = parameters.get(i);
                 JetTypeReference typeReference = parameter.getTypeReference();
                 if (typeReference == null) {
                     throw new UnsupportedOperationException("Type inference for parameters is not implemented yet");
                 }
-                VariableDescriptor variableDescriptor = classDescriptorResolver.resolveLocalVariableDescriptor(functionDescriptor, scope, parameter);
+                JetType type = typeResolver.resolveType(scope, typeReference);
-                parameterDescriptors.put(parameter.getName(), variableDescriptor);
+                ValueParameterDescriptor valueParameterDescriptor = classDescriptorResolver.resolveValueParameterDescriptor(functionDescriptor, parameter, i, type);
-                parameterTypes.add(variableDescriptor.getOutType());
+                parameterTypes.add(valueParameterDescriptor.getOutType());
+                valueParameterDescriptors.add(valueParameterDescriptor);
             }
+
+            JetType effectiveReceiverType = receiverTypeRef == null ? null : receiverType;
+            functionDescriptor.initialize(effectiveReceiverType, Collections.<TypeParameterDescriptor>emptyList(), valueParameterDescriptors, null);
+            trace.recordDeclarationResolution(expression, functionDescriptor);
+
+            JetTypeReference returnTypeRef = expression.getReturnTypeRef();
             JetType returnType;
             if (returnTypeRef != null) {
                 returnType = typeResolver.resolveType(scope, returnTypeRef);
             } else {
                 WritableScope writableScope = new WritableScopeImpl(scope, functionDescriptor, trace.getErrorHandler());
-                for (VariableDescriptor variableDescriptor : parameterDescriptors.values()) {
+                for (VariableDescriptor variableDescriptor : valueParameterDescriptors) {
                     writableScope.addVariableDescriptor(variableDescriptor);
                 }
                 writableScope.setThisType(receiverType);
-                returnType = getBlockReturnedType(writableScope, body);
+                returnType = getBlockReturnedType(writableScope, expression.getBody());
             }
-            JetType effectiveReceiverType = receiverTypeRef == null ? null : receiverType;
             JetType safeReturnType = returnType == null ? ErrorUtils.createErrorType("<return type>") : returnType;
+            functionDescriptor.setReturnType(safeReturnType);
+
+
             result = JetStandardClasses.getFunctionType(Collections.<Annotation>emptyList(), effectiveReceiverType, parameterTypes, safeReturnType);
         }
 
@@ -928,7 +938,6 @@ public class JetTypeInferrer {
 
         @Override
         public void visitThisExpression(JetThisExpression expression) {
-            // TODO : qualified this, e.g. this@Foo<Bar>
             JetType thisType = null;
             String labelName = expression.getLabelName();
             if (labelName != null) {
@@ -941,15 +950,39 @@ public class JetTypeInferrer {
                     if (declarationDescriptor instanceof ClassDescriptor) {
                         ClassDescriptor classDescriptor = (ClassDescriptor) declarationDescriptor;
                         thisType = classDescriptor.getDefaultType();
-                        trace.recordReferenceResolution(targetLabel, classDescriptor);
+                    }
-                        trace.recordReferenceResolution(expression.getThisReference(), classDescriptor);
+                    else if (declarationDescriptor instanceof FunctionDescriptor) {
+                        FunctionDescriptor functionDescriptor = (FunctionDescriptor) declarationDescriptor;
+                        thisType = functionDescriptor.getReceiverType();
                     }
                     else {
                         throw new UnsupportedOperationException(); // TODO
                     }
+                    trace.recordReferenceResolution(targetLabel, declarationDescriptor);
+                    trace.recordReferenceResolution(expression.getThisReference(), declarationDescriptor);
                 }
                 else if (size == 0) {
-                    trace.getErrorHandler().unresolvedReference(targetLabel);
+                    // This uses the info written by the control flow processor
+                    PsiElement psiElement = trace.getBindingContext().resolveToDeclarationPsiElement(targetLabel);
+                    if (psiElement instanceof JetFunctionLiteralExpression) {
+                        DeclarationDescriptor declarationDescriptor = trace.getBindingContext().getDeclarationDescriptor(psiElement);
+                        if (declarationDescriptor instanceof FunctionDescriptor) {
+                            thisType = ((FunctionDescriptor) declarationDescriptor).getReceiverType();
+                            if (thisType == null) {
+                                thisType = JetStandardClasses.getNothingType();
+                            }
+                            else {
+                                trace.recordReferenceResolution(targetLabel, declarationDescriptor);
+                                trace.recordReferenceResolution(expression.getThisReference(), declarationDescriptor);
+                            }
+                        }
+                        else {
+                            trace.getErrorHandler().unresolvedReference(targetLabel);
+                        }
+                    }
+                    else {
+                        trace.getErrorHandler().unresolvedReference(targetLabel);
+                    }
                 }
                 else {
                     trace.getErrorHandler().genericError(targetLabel.getNode(), "Ambiguous label");

idea/src/org/jetbrains/jet/plugin/JetQuickDocumentationProvider.java

@@ -34,6 +34,13 @@ public class JetQuickDocumentationProvider implements DocumentationProvider {
             if (declarationDescriptor != null) {
                 return render(declarationDescriptor);
             }
+            PsiElement psiElement = bindingContext.resolveToDeclarationPsiElement(ref);
+            if (psiElement != null) {
+                declarationDescriptor = bindingContext.getDeclarationDescriptor(psiElement);
+                if (declarationDescriptor != null) {
+                    return render(declarationDescriptor);
+                }
+            }
             return "Unresolved";
         }
 

idea/testData/checker/QualifiedThis.jet

@@ -20,3 +20,22 @@ fun foo() : Unit {
   <error>this</error>
   this<error>@a</error>
 }
+
+namespace closures {
+    class A(val a:Int) {
+
+      class B() {
+        val x = this@B : B
+        val y = this@A : A
+        val z = this : B
+        val Int.xx = this : Int
+        fun Char.xx() {
+          this : Char
+          val a = {Double.() => this : Double + this@xx : Char}
+          val b = @a{Double.() => this@a : Double + this@xx : Char}
+          val c = @a{() => <error>this@a</error> + this@xx : Char}
+          return (@a{Double.() => this@a : Double + this@xx : Char})
+        }
+      }
+    }
+}

idea/testData/resolve/Classifiers.jet

@@ -8,6 +8,8 @@ namespace qualified_this {
         ~xx~val Int.xx = `xx`this : Int
         ~xx()~fun Int.xx() {
             `xx()`this : Int
+            val a = {Int.() => `xx()`this`xx()`@xx + this}
+
         }
       }
     }

idea/tests/org/jetbrains/jet/types/JetTypeCheckerTest.java

@@ -12,7 +12,10 @@ import org.jetbrains.jet.lang.descriptors.*;
 import org.jetbrains.jet.lang.psi.JetChangeUtil;
 import org.jetbrains.jet.lang.psi.JetClass;
 import org.jetbrains.jet.lang.psi.JetExpression;
-import org.jetbrains.jet.lang.resolve.*;
+import org.jetbrains.jet.lang.resolve.ClassDescriptorResolver;
+import org.jetbrains.jet.lang.resolve.JetScope;
+import org.jetbrains.jet.lang.resolve.JetScopeAdapter;
+import org.jetbrains.jet.lang.resolve.TypeResolver;
 import org.jetbrains.jet.lang.types.*;
 import org.jetbrains.jet.parsing.JetParsingTest;