private EnumerablePropertySource<?> singleton(String key, Object value) {
		Map<String, Object> map = Collections.singletonMap(key, value);
		return new MapPropertySource("ps-" + random.nextInt(), map);
	}
Tests for {@link ModuleEnvironment}.

@author Eric Bottard
spring-xd-module/src/test/java/org/springframework/xd/module/core/ModuleEnvironmentTests.java