@Override
			public void modifyPrivate(ProgramDB program) throws Exception {
				DataTypeManager dtm = program.getDataTypeManager();
				Structure inner = (Structure) dtm.getDataType(rootPath, "inner");

				Structure outer = new StructureDataType("outer", 0);
				outer.add(new ByteDataType());
				outer.add(inner);
				outer.setPackingEnabled(true);

				// Add outer struct
				dtm.addDataType(outer, DataTypeConflictHandler.DEFAULT_HANDLER);
			}
Data type merge tests with fixup for data types added in My program.
Ghidra/Features/Base/src/test.slow/java/ghidra/app/merge/datatypes/DataTypeMergeFixupTest.java