GROOVY-11900: grab adds static constructor to annotation definition

Author: paulk-asert

src/main/java/groovy/grape/GrabAnnotationTransformation.java

@@ -205,6 +205,8 @@ public void visit(final ASTNode[] nodes, final SourceUnit source) {
         Collection<Map<String,Object>> grabExcludeMaps = new ArrayList<>();
 
         for (ClassNode classNode : sourceUnit.getAST().getClasses()) {
+            if (classNode.isAnnotationDefinition()) continue; // GROOVY-11900
+
             grabAnnotations         = new ArrayList<>();
             grabExcludeAnnotations  = new ArrayList<>();
             grabConfigAnnotations   = new ArrayList<>();

src/main/java/org/codehaus/groovy/classgen/AnnotationVisitor.java

@@ -144,8 +144,9 @@ private boolean validateEnumConstant(final Expression exp) {
     private boolean checkIfMandatoryAnnotationValuesPassed(final AnnotationNode node) {
         boolean ok = true;
         for (MethodNode mn : node.getClassNode().getMethods()) {
-            if (!mn.hasAnnotationDefault() && !node.getMembers().containsKey(mn.getName()) && !"dataVariableNames".equals(mn.getName())) {
-                // TODO: https://github.com/spockframework/spock/issues/1549               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+            // "dataVariableNames" was an incorrectly set up variable in Spock, now removed, but exclusion kept for legacy versions
+            // https://github.com/spockframework/spock/pull/1596/changes/513bb6e7e19
+            if (!mn.hasAnnotationDefault() && !mn.isStaticConstructor() && !node.getMembers().containsKey(mn.getName()) && !"dataVariableNames".equals(mn.getName())) {
                 addError("No explicit/default value found for annotation attribute '" + mn.getName() + "'", node);
                 ok = false;
             }