private Cache cacheWithOneRootRegion(String regionName) {
    Cache cache = mock(Cache.class);
    when(regionAttributes.getDataPolicy()).thenReturn(mock(DataPolicy.class));
    when(regionAttributes.getScope()).thenReturn(mock(Scope.class));
    when(region.getFullPath()).thenReturn(SEPARATOR + regionName);
    when(region.subregions(anyBoolean())).thenReturn(Collections.emptySet());
    when(region.getAttributes()).thenReturn(regionAttributes);
    when(cache.rootRegions()).thenReturn(Collections.singleton(region));
    return cache;
  }
Characterization unit tests for {@code GetRegionsFunction};
geode-gfsh/src/test/java/org/apache/geode/management/internal/cli/functions/GetRegionsFunctionTest.java