clean up enum and comma in annotation

java/piranha/src/main/java/com/uber/piranha/XPFlagCleaner.java

@@ -57,6 +57,7 @@
 import com.sun.source.tree.VariableTree;
 import com.sun.source.util.TreePath;
 import com.sun.tools.javac.code.Symbol;
+import com.sun.tools.javac.tree.JCTree;
 import com.uber.piranha.config.Config;
 import com.uber.piranha.config.PiranhaConfigurationException;
 import com.uber.piranha.config.PiranhaEnumRecord;
@@ -75,6 +76,7 @@
 import java.util.OptionalInt;
 import java.util.Set;
 import java.util.stream.Collectors;
+import java.util.stream.IntStream;
 import java.util.stream.Stream;
 import javax.annotation.Nullable;
 import javax.lang.model.element.ElementKind;
@@ -1374,7 +1376,7 @@ public Description matchMethod(MethodTree tree, VisitorState state) {
       // Note that the AST elements referenced by deletableAnnotations and deletableIdentifiers
       // should not overlap, given the logic above, so deleting each independently is safe.
       for (ExpressionTree expr : deletableIdentifiers) {
-        fixBuilder.delete(expr);
+        fixBuilder = deleteExprWithComma(state, expr, resolvedTestAnnotations, fixBuilder);
         decrementAllSymbolUsages(expr, state, fixBuilder);
       }
       for (AnnotationTree at : deletableAnnotations) {
@@ -1564,6 +1566,66 @@ private boolean endsWithReturn(StatementTree stmt) {
     return false;
   }
 
+  /** removes enum in annotation and the comma if there is more than one enum in it */
+  private SuggestedFix.Builder deleteExprWithComma(
+      VisitorState state,
+      ExpressionTree expressionTree,
+      ImmutableSet<ResolvedTestAnnotation> resolvedTestAnnotations,
+      SuggestedFix.Builder fixBuilder) {
+    for (ResolvedTestAnnotation resolvedTestAnnotation : resolvedTestAnnotations) {
+
+      // remove the comma before or after the enum depending on the index
+      int index =
+          IntStream.range(0, resolvedTestAnnotation.getFlags().size())
+              .filter(i -> resolvedTestAnnotation.getFlags().get(i).getValue().equals(xpFlagName))
+              .findFirst()
+              .orElse(-1);
+      if (index != -1) {
+        JCTree node = (JCTree) resolvedTestAnnotation.getSourceTree();
+        int startAbsolute = node.getStartPosition();
+        int lower = ((JCTree) expressionTree).getStartPosition() - startAbsolute;
+        int upper = state.getEndPosition(expressionTree) - startAbsolute;
+        CharSequence source = state.getSourceForNode(node);
+
+        lower = getLower(source, lower, index, resolvedTestAnnotation.getFlags().size());
+
+        upper = getUpper(source, upper);
+
+        fixBuilder.replace(startAbsolute + lower, startAbsolute + upper, "");
+      }
+    }
+    return fixBuilder;
+  }
+
+  private int getLower(CharSequence source, int lower, int index, int flagSize) {
+    while (lower >= 0
+        && source.charAt(lower) != '{'
+        && source.charAt(lower) != '='
+        && source.charAt(lower) != ',') {
+      lower--;
+    }
+    // do not remove { or = neither the comma when it is not the last enum
+    if (source.charAt(lower) == '{'
+        || source.charAt(lower) == '='
+        || (index != flagSize - 1 && source.charAt(lower) == ',')) {
+      lower++;
+    }
+    return lower;
+  }
+
+  private int getUpper(CharSequence source, int upper) {
+    while (upper < source.length()
+        && source.charAt(upper) != ','
+        && source.charAt(upper) != '}'
+        && source.charAt(upper) != ')') {
+      upper++;
+    }
+    if (source.charAt(upper) == ',') {
+      upper++;
+    }
+    return upper;
+  }
+
   /**
    * A small tuple of counters for scanning unit tests to be deleted by the setters heuristic. See
    * {@link #shouldCleanBySetters(MethodTree, VisitorState)}