@Test
	public void testCollidingModuleComposeWithRegularModule() {
		CommandResult result = getShell().executeCommand(
				"module compose tcp --definition \"time | transform\"");
		assertEquals("There is already a module named 'tcp' with type 'source'\n", result.getException().getMessage());

	}
This tests that options passed at usage time of a composed module are override definition values.
spring-xd-shell/src/test/java/org/springframework/xd/shell/command/AbstractModuleCommandsTests.java