"annotation" is now parsed as an identifier. It is no longer a soft keyword.

Sometimes it's allowed to parse "annotation" unescaped even if other annotations must be escaped.
A set of annotations and their options tests.
A swarm of existing tests fixed (mostly kotlin.annotation.annotation() added to txt-files).
STUB_VERSION increased. Some quick fixes slightly changed.

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

@@ -124,8 +124,6 @@ public interface Errors {
     DiagnosticFactory0<PsiElement> ANNOTATION_CLASS_WITH_BODY = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<JetTypeReference> INVALID_TYPE_OF_ANNOTATION_MEMBER = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<JetTypeReference> NULLABLE_TYPE_OF_ANNOTATION_MEMBER = DiagnosticFactory0.create(ERROR);
-    DiagnosticFactory0<JetModifierListOwner> ILLEGAL_ANNOTATION_KEYWORD =
-            DiagnosticFactory0.create(ERROR, modifierSetPosition(JetTokens.ANNOTATION_KEYWORD));
     DiagnosticFactory0<JetExpression> ANNOTATION_PARAMETER_MUST_BE_CONST = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<JetExpression> ANNOTATION_PARAMETER_MUST_BE_KCLASS_LITERAL = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<JetExpression> ANNOTATION_PARAMETER_MUST_BE_ENUM_CONST = DiagnosticFactory0.create(ERROR);

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

@@ -613,7 +613,6 @@ public class DefaultErrorMessages {
         MAP.put(ANNOTATION_CLASS_WITH_BODY, "Body is not allowed for annotation class");
         MAP.put(INVALID_TYPE_OF_ANNOTATION_MEMBER, "Invalid type of annotation member");
         MAP.put(NULLABLE_TYPE_OF_ANNOTATION_MEMBER, "An annotation parameter cannot be nullable");
-        MAP.put(ILLEGAL_ANNOTATION_KEYWORD, "''annotation'' keyword is only applicable for class");
         MAP.put(ANNOTATION_PARAMETER_MUST_BE_CONST, "An annotation parameter must be a compile-time constant");
         MAP.put(ANNOTATION_PARAMETER_MUST_BE_ENUM_CONST, "An enum annotation parameter must be a enum constant");
         MAP.put(ANNOTATION_PARAMETER_MUST_BE_KCLASS_LITERAL, "An annotation parameter must be a class literal (T::class)");

compiler/frontend/src/org/jetbrains/kotlin/lexer/JetTokens.java

@@ -145,7 +145,6 @@ public interface JetTokens {
     JetModifierKeywordToken ENUM_KEYWORD      = JetModifierKeywordToken.softKeywordModifier("enum");
     JetModifierKeywordToken OPEN_KEYWORD      = JetModifierKeywordToken.softKeywordModifier("open");
     JetModifierKeywordToken INNER_KEYWORD     = JetModifierKeywordToken.softKeywordModifier("inner");
-    JetModifierKeywordToken ANNOTATION_KEYWORD = JetModifierKeywordToken.softKeywordModifier("annotation");
     JetModifierKeywordToken OVERRIDE_KEYWORD  = JetModifierKeywordToken.softKeywordModifier("override");
     JetModifierKeywordToken PRIVATE_KEYWORD   = JetModifierKeywordToken.softKeywordModifier("private");
     JetModifierKeywordToken PUBLIC_KEYWORD    = JetModifierKeywordToken.softKeywordModifier("public");
@@ -172,7 +171,7 @@ public interface JetTokens {
     );
 
     TokenSet SOFT_KEYWORDS = TokenSet.create(FILE_KEYWORD, IMPORT_KEYWORD, WHERE_KEYWORD, BY_KEYWORD, GET_KEYWORD,
-                                             SET_KEYWORD, ABSTRACT_KEYWORD, ENUM_KEYWORD, OPEN_KEYWORD, INNER_KEYWORD, ANNOTATION_KEYWORD,
+                                             SET_KEYWORD, ABSTRACT_KEYWORD, ENUM_KEYWORD, OPEN_KEYWORD, INNER_KEYWORD,
                                              OVERRIDE_KEYWORD, PRIVATE_KEYWORD, PUBLIC_KEYWORD, INTERNAL_KEYWORD, PROTECTED_KEYWORD,
                                              CATCH_KEYWORD, FINALLY_KEYWORD, OUT_KEYWORD, FINAL_KEYWORD, VARARG_KEYWORD, REIFIED_KEYWORD,
                                              DYNAMIC_KEYWORD, COMPANION_KEYWORD, CONSTRUCTOR_KEYWORD, INIT_KEYWORD, SEALED_KEYWORD
@@ -185,7 +184,7 @@ public interface JetTokens {
      */
     JetModifierKeywordToken[] MODIFIER_KEYWORDS_ARRAY =
             new JetModifierKeywordToken[] {
-                    ABSTRACT_KEYWORD, ENUM_KEYWORD, OPEN_KEYWORD, INNER_KEYWORD, ANNOTATION_KEYWORD, OVERRIDE_KEYWORD, PRIVATE_KEYWORD,
+                    ABSTRACT_KEYWORD, ENUM_KEYWORD, OPEN_KEYWORD, INNER_KEYWORD, OVERRIDE_KEYWORD, PRIVATE_KEYWORD,
                     PUBLIC_KEYWORD, INTERNAL_KEYWORD, PROTECTED_KEYWORD, OUT_KEYWORD, IN_KEYWORD, FINAL_KEYWORD, VARARG_KEYWORD,
                     REIFIED_KEYWORD, COMPANION_KEYWORD, SEALED_KEYWORD
             };

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

@@ -25,6 +25,7 @@ import com.intellij.psi.impl.CheckUtil
 import com.intellij.psi.impl.source.codeStyle.CodeEditUtil
 import com.intellij.psi.stubs.IStubElementType
 import org.jetbrains.kotlin.JetNodeTypes
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.lexer.JetTokens
 import org.jetbrains.kotlin.psi.stubs.KotlinClassOrObjectStub
 import org.jetbrains.kotlin.psi.stubs.elements.JetStubElementTypes
@@ -64,7 +65,16 @@ abstract public class JetClassOrObject : JetTypeParameterListOwnerStub<KotlinCla
 
     public fun getSecondaryConstructors(): List<JetSecondaryConstructor> = getBody()?.getSecondaryConstructors().orEmpty()
 
-    public fun isAnnotation(): Boolean = hasModifier(JetTokens.ANNOTATION_KEYWORD)
+    public fun isAnnotation(): Boolean = hasAnnotation(KotlinBuiltIns.FQ_NAMES.annotation.shortName().asString())
+
+    private fun hasAnnotation(name: String): Boolean {
+        for (entry in getAnnotationEntries()) {
+            val typeReference = entry.getTypeReference()
+            val userType = typeReference?.getStubOrPsiChild(JetStubElementTypes.USER_TYPE) ?: continue
+            if (name == userType.getReferencedName()) return true
+        }
+        return false
+    }
 
     public override fun delete() {
         CheckUtil.checkWritable(this);

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

@@ -102,4 +102,4 @@ private val MODIFIERS_ORDER = listOf(PUBLIC_KEYWORD, PROTECTED_KEYWORD, PRIVATE_
                                      FINAL_KEYWORD, OPEN_KEYWORD, ABSTRACT_KEYWORD,
                                      OVERRIDE_KEYWORD,
                                      INNER_KEYWORD,
-                                     ANNOTATION_KEYWORD, ENUM_KEYWORD, COMPANION_KEYWORD)
+                                     ENUM_KEYWORD, COMPANION_KEYWORD)

compiler/frontend/src/org/jetbrains/kotlin/psi/stubs/elements/JetFileElementType.java

@@ -36,7 +36,7 @@ import org.jetbrains.kotlin.psi.stubs.impl.KotlinFileStubImpl;
 import java.io.IOException;
 
 public class JetFileElementType extends IStubFileElementType<KotlinFileStub> {
-    public static final int STUB_VERSION = 49;
+    public static final int STUB_VERSION = 50;
 
     private static final String NAME = "kotlin.FILE";
 

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

@@ -128,9 +128,6 @@ public class DeclarationsChecker {
         if (declaration.hasModifier(JetTokens.ENUM_KEYWORD)) {
             trace.report(ILLEGAL_ENUM_ANNOTATION.on(declaration));
         }
-        if (declaration.hasModifier(JetTokens.ANNOTATION_KEYWORD)) {
-            trace.report(ILLEGAL_ANNOTATION_KEYWORD.on(declaration));
-        }
     }
 
     private void checkModifiersAndAnnotationsInPackageDirective(JetFile file) {

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallExpressionResolver.java

@@ -269,7 +269,7 @@ public class CallExpressionResolver {
         else if (parent instanceof JetParameter) {
             JetClass jetClass = PsiTreeUtil.getParentOfType(parent, JetClass.class);
             if (jetClass != null) {
-                return jetClass.hasModifier(JetTokens.ANNOTATION_KEYWORD);
+                return jetClass.isAnnotation();
             }
         }
         return false;