@Test
	public void testApplyFunctionOnlyInP1() throws Exception {
		// In p1 not in p2.
		int transactionID = p2.startTransaction("Test Transaction");
		p2.getFunctionManager().removeFunction(addr(0x10030d2));
		p2.endTransaction(transactionID, true);

		programMerge =
			new ProgramMergeManager(p1, p2, new AddressSet(addr(0x10030d2), addr(0x10030d7)));
		AddressSet as = new AddressSet(addr(0x10030d2), addr(0x10030d2));
		programMerge.setDiffFilter(new ProgramDiffFilter(ProgramDiffFilter.FUNCTION_DIFFS));
		programMerge.setMergeFilter(
			new ProgramMergeFilter(ProgramMergeFilter.FUNCTIONS, ProgramMergeFilter.REPLACE));
		assertEquals(as, programMerge.getFilteredDifferences());
		programMerge.merge(as, TaskMonitor.DUMMY);
		assertEquals(new AddressSet(), programMerge.getFilteredDifferences());
	}
Test that programMerge can determine there is a function difference when
the function is only in Program1.
Ghidra/Features/Base/src/test.slow/java/ghidra/program/util/ProgramMerge3Test.java