Sonar Java: "Unexpected expression METHOD_INVOCATION" on valid Java code

public class testSonarJava {

	private static final ThreadLocal<List<String>[]> foo = new ThreadLocal<List<String>[]>();

	public void testSonarPASS() {
		foo.set(new ArrayList[1]);
		List<String>[] lists = foo.get();
		lists[0] = null;
	}

	public void testSonarFAIL() {
		foo.set(new ArrayList[1]);
		foo.get()[0] = null;
	}

}

When trying to analyze this class, I get analysis error on testSonarFAIL method: Unexpected expression METHOD_INVOCATION

testSonarPASS is analyzed without any issues.