@Test
	public void testCyclicDependencyProblem7() {
		Structure structure = createStructure("TestStructure", 0);
		structure.add(union);
		TypeDef typeDef = createTypeDef(structure);
		try {
			union.add(typeDef);
			Assert.fail(
				"Shouldn't be able to add a typedef of a strucutre, which contains this union, to this union.");
		}
		catch (IllegalArgumentException e) {
			// Should get an exception from adding the structure typedef to the union.
		}
		try {
			union.insert(0, typeDef);
			Assert.fail(
				"Shouldn't be able to insert a typedef of a structure, which contains this union, to this union.");
		}
		catch (IllegalArgumentException e) {
			// Should get an exception from inserting the structure typedef to the union.
		}
	}
Test that a structure can't contain a typedef of a union that contains that structure.
Ghidra/Features/Base/src/test/java/ghidra/program/model/data/UnionDataTypeTest.java