@Test
    void requireThatKeyIsEscapedInToString() {
        assertEquals("foo=10+[2..3]", new RangeEdgePartition("foo=10", 10, 2, 3).toString());
        assertEquals("'\\foo=10'+[2..3]", new RangeEdgePartition("\foo=10", 10, 2, 3).toString());
        assertEquals("'\\x27foo\\x27=10'+[2..3]", new RangeEdgePartition("'foo'=10", 10, 2, 3).toString());
    }
@author <a href="mailto:magnarn@yahoo-inc.com">Magnar Nedland</a>
predicate-search-core/src/test/java/com/yahoo/document/predicate/RangeEdgePartitionTest.java