in src/main/java/com/googlesource/gerrit/plugins/deleteproject/DeletePreconditions.java [180:190]
private void assertHasNoTags(Project.NameKey projectNameKey) throws CannotDeleteProjectException {
try (Repository repo = repoManager.openRepository(projectNameKey)) {
if (!repo.getRefDatabase().getRefsByPrefix(REFS_TAGS).isEmpty()) {
throw new CannotDeleteProjectException(
String.format("Project %s has tags", projectNameKey));
}
} catch (IOException e) {
throw new CannotDeleteProjectException(
String.format("Unable to verify if project %s has tags", projectNameKey), e);
}
}