Support @receiver annotations

compiler/backend/src/org/jetbrains/kotlin/codegen/FunctionCodegen.java

@@ -254,6 +254,14 @@ public class FunctionCodegen {
                 v.getSerializationBindings().put(INDEX_FOR_VALUE_PARAMETER, parameter, i);
                 AnnotationCodegen.forParameter(i, mv, typeMapper).genAnnotations(parameter, parameterSignature.getAsmType());
             }
+            else if (kind == JvmMethodParameterKind.RECEIVER) {
+                Annotated annotationHolder = (functionDescriptor instanceof PropertyAccessorDescriptor)
+                                             ? ((PropertyAccessorDescriptor) functionDescriptor).getCorrespondingProperty()
+                                             : functionDescriptor;
+                AnnotationCodegen annotationCodegen = AnnotationCodegen.forParameter(i, mv, typeMapper);
+                Annotated targetedAnnotations = new AnnotatedWithAdditionalAnnotations(null, annotationHolder);
+                annotationCodegen.genAnnotations(targetedAnnotations, parameterSignature.getAsmType(), RECEIVER);
+            }
         }
     }
 

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

@@ -137,6 +137,7 @@ public interface Errors {
     DiagnosticFactory0<PsiElement> INAPPLICABLE_GET_TARGET = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<PsiElement> INAPPLICABLE_SET_TARGET = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<PsiElement> INAPPLICABLE_TARGET_PROPERTY_IMMUTABLE = DiagnosticFactory0.create(ERROR);
+    DiagnosticFactory0<PsiElement> INAPPLICABLE_RECEIVER_TARGET = DiagnosticFactory0.create(ERROR);
 
     // Classes and traits
 

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

@@ -130,6 +130,7 @@ public class DefaultErrorMessages {
         MAP.put(INAPPLICABLE_GET_TARGET, "''@get:'' annotations could be applied only to property declarations");
         MAP.put(INAPPLICABLE_SET_TARGET, "''@set:'' annotations could be applied only to property declarations");
         MAP.put(INAPPLICABLE_TARGET_PROPERTY_IMMUTABLE, "Property must be mutable");
+        MAP.put(INAPPLICABLE_RECEIVER_TARGET, "''@receiver:'' annotations could be applied only to extension function or extension property declarations");
 
         MAP.put(REDUNDANT_MODIFIER, "Modifier ''{0}'' is redundant because ''{1}'' is present", TO_STRING, TO_STRING);
         MAP.put(ABSTRACT_MODIFIER_IN_TRAIT, "Modifier ''abstract'' is redundant in interface");

compiler/frontend/src/org/jetbrains/kotlin/psi/JetAnnotationUseSiteTarget.kt

@@ -41,6 +41,7 @@ public class JetAnnotationUseSiteTarget : JetElementImplStub<KotlinPlaceHolderSt
             JetTokens.PROPERTY_KEYWORD -> AnnotationUseSiteTarget.PROPERTY
             JetTokens.GET_KEYWORD -> AnnotationUseSiteTarget.PROPERTY_GETTER
             JetTokens.SET_KEYWORD -> AnnotationUseSiteTarget.PROPERTY_SETTER
+            JetTokens.RECEIVER_KEYWORD -> AnnotationUseSiteTarget.RECEIVER
             else -> throw IllegalStateException("Unknown annotation target " + node.getText())
         }
     }

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

@@ -244,6 +244,17 @@ public class ModifiersChecker {
                         reportIfNotMutableProperty(descriptor, annotation, INAPPLICABLE_SET_TARGET);
                         break;
                     }
+                    case RECEIVER: {
+                        if (!(descriptor instanceof FunctionDescriptor)  && !(descriptor instanceof PropertyDescriptor)) {
+                            reportAnnotationTargetNotApplicable(annotation, INAPPLICABLE_RECEIVER_TARGET);
+                            break;
+                        }
+
+                        if (((CallableMemberDescriptor) descriptor).getExtensionReceiverParameter() == null) {
+                            reportAnnotationTargetNotApplicable(annotation, INAPPLICABLE_RECEIVER_TARGET);
+                        }
+                        break;
+                    }
                 }
             }
         }

core/descriptors/src/org/jetbrains/kotlin/descriptors/annotations/AnnotationUseSiteTarget.kt

@@ -21,7 +21,8 @@ public enum class AnnotationUseSiteTarget(renderName: String? = null) {
     FILE(),
     PROPERTY(),
     PROPERTY_GETTER("get"),
-    PROPERTY_SETTER("set");
+    PROPERTY_SETTER("set"),
+    RECEIVER();
 
     public val renderName: String = renderName ?: name().toLowerCase()
 }