@TestFactory
    Stream<DynamicTest> testSingleQuote() {
        return TestUtil.buildDynamicTestStream()
                .withInputAndOutputType(String.class)
                .withTestFunction(testCase -> StringUtil.singleQuote(testCase.getInput()))
                .withSimpleEqualityAssertion()
                .addCase(null, "''")
                .addCase("", "''")
                .addCase("x", "'x'")
                .addCase("o'neil", "'o'neil'")
                .build();
    }
Make sure the two functions are reversible
stroom-util-shared/src/test/java/stroom/util/shared/TestStringUtil.java