@Test
	public void testChangeFunctionPurge() throws Exception {

		mtf.initialize("NotepadMergeListingTest", new OriginalProgramModifierListener() {

			@Override
			public void modifyOriginal(ProgramDB program) {
				try {
					Function applesFunction =
						createExternalFunction(program, new String[] { "user32.dll", "apples" },
							addr(program, "77db1020"), new ByteDataType(), SourceType.USER_DEFINED);
					assertNotNull(applesFunction);
					Parameter parameter1 = new ParameterImpl("P1", new DWordDataType(), program);
					parameter1.setComment("Test Parameter Comment");
					applesFunction.addParameter(parameter1, SourceType.USER_DEFINED);

					Function orangesFunction =
						createExternalFunction(program, new String[] { "user32.dll", "oranges" });
					addParameter(orangesFunction, "A1", SourceType.USER_DEFINED,
						new DWordDataType(), "Test Parameter Comment");
					addParameter(orangesFunction, "A2", SourceType.USER_DEFINED,
						new DWordDataType(), "Test Parameter Comment");
				}
				catch (Exception e) {
					Assert.fail(e.getMessage());
				}
			}

			@Override
			public void modifyLatest(ProgramDB program) {
				try {
					Function func =
						getExternalFunction(program, new String[] { "user32.dll", "apples" });
					func.setStackPurgeSize(5);

					func = getExternalFunction(program, new String[] { "user32.dll", "oranges" });
					func.setStackPurgeSize(3);
				}
				catch (Exception e) {
					Assert.fail(e.getMessage());
				}
			}

			@Override
			public void modifyPrivate(ProgramDB program) {
				try {
					Function func =
						getExternalFunction(program, new String[] { "user32.dll", "apples" });
					func.setStackPurgeSize(8);

					func = getExternalFunction(program, new String[] { "user32.dll", "oranges" });
					func.setStackPurgeSize(2);
				}
				catch (Exception e) {
					Assert.fail(e.getMessage());
				}
			}
		});

		executeMerge(ASK_USER);
		chooseVariousOptionsForConflictType("Resolve Function Conflict",
			new int[] { INFO_ROW, KEEP_LATEST });
		chooseVariousOptionsForConflictType("Resolve Function Conflict",
			new int[] { INFO_ROW, KEEP_MY });
		waitForMergeCompletion();

		Function func = getExternalFunction(resultProgram, new String[] { "user32.dll", "apples" });
		assertEquals(5, func.getStackPurgeSize());

		func = getExternalFunction(resultProgram, new String[] { "user32.dll", "oranges" });
		assertEquals(2, func.getStackPurgeSize());
	}
Remove a register parameter vs change the register on a register parameter.

@throws Exception
Ghidra/Features/Base/src/test.slow/java/ghidra/app/merge/listing/ExternalFunctionMergeManagerTest.java