Examine SchemaContextUtil.findCorrectTargetFromGrouping()

for (UsesNode u : m.getUses()) {
SchemaNode targetGrouping = findNodeInSchemaContext(ctx, u.getGroupingPath().getPath());
if (!(targetGrouping instanceof GroupingDefinition))

{ throw new IllegalArgumentException(String.format("Failed to generate code for augment in %s", u)); }

GroupingDefinition gr = (GroupingDefinition) targetGrouping;
result = gr.getDataChildByName(node.getQName().getLocalName());
}

Seems to be missing break; after result.