Checker.checkArgumentNotNull(localeSupport);
checkNotBuilt();
this.localeSupport = localeSupport;
return this;
}
<BUG>public MustacheEngineBuilder registerCallback(EngineBuiltCallback callback) {
Checker.checkArgumentNotNull(callback);</BUG>
checkNotBuilt();
this.engineReadyCallbacks.add(callback);
return this;

Checker.checkArgumentNotNull(localeSupport);
checkNotBuilt();
this.localeSupport = localeSupport;
return this;
}
public MustacheEngineBuilder registerCallback(
EngineBuiltCallback callback) {
Checker.checkArgumentNotNull(callback);
checkNotBuilt();
this.engineReadyCallbacks.add(callback);
return this;
