Spock testing a ResultSet in Groovy

Question

Here is what I have so far:

def "If there are results then return true otherwise return false"() {
    given:
    ResultSet resultSet = Mock()

    expect:
    resultSet.next()
}

I am trying to test a boolean method checkIfRowExists(int id, int foreignKey) in class CheckActuateProjectSetServiceImpl. It returns true if row exists and false otherwise.

How would I go about solving this?

public boolean checkIfRowExists(int id, int foreignKey){
    Resultset resultSet = checkIfRowExistsResultSet(id, foreignKey)

    return false;
}

The above method doesn't have the correct implementation as of yet because I'm trying to write the test first before I implement the solution.

Thanks

Think we would need to know what `CheckActuateProjectSetServiceImpl` looked like... How does the method have a resultset? There doesn't seem to be anything passed in the method definition — tim_yates, Jan 05 '19 at 08:46
It calls a private method named checkIfRowExistsResultSet(int id, int foreignkey) I'll update... thanks for your input — ShadyBears, Jan 05 '19 at 08:55

score 2 · Accepted Answer · answered Jan 05 '19 at 21:02

If I were on your place I would do the next TDD steps.

Start with a test for one test case only:

def "If there not are results then return false"() {
    given:
    def service = new CheckActuateProjectSetServiceImpl()

    expect:
    !service.checkIfRowExists(1, 2)
}

Implement the method to satisfy the test:

boolean checkIfRowExists(int id, int foreignKey) {
    return false;
}

Add new test for case when there are some result:

def "If there are results then return true"() {
    given:
    def service = new CheckActuateProjectSetServiceImpl()

    expect:
    service.checkIfRowExists(1, 2)
}

Now we are forced to implement our method. The method will do a DB query and check the actual result set for emptiness. Because the DB query is out of unit test scope we extract it to a separate method and will override it in the test later:

boolean checkIfRowExists(int id, int foreignKey) throws SQLException {
    ResultSet resultSet = getResultSet(id, foreignKey);
    return resultSet.next();
}

ResultSet getResultSet(int id, int foreignKey) {
    return null; // TODO should be implemented
}

Now our test is failed with NullPointerException because getResultSet() returns null. Lets return a mocked ResultSet which returns true on next() call:

def "If there are results then return true"() {
    given:
    ResultSet mockedResultSet = Mock(ResultSet)
    mockedResultSet.next() >> true

    def service = new CheckActuateProjectSetServiceImpl() {
        @Override
        def ResultSet getResultSet(int id, int foreignKey) {
            return mockedResultSet;
        }
    }

    expect:
    service.checkIfRowExists(1, 2)
}

The test is green now.

The first test is to be fixed as well, mock to return false on next() call:

def "If there not are results then return false"() {
    given:
    ResultSet mockedResultSet = Mock(ResultSet)
    mockedResultSet.next() >> false

    def service = new CheckActuateProjectSetServiceImpl() {
        @Override
        def ResultSet getResultSet(int id, int foreignKey) {
            return mockedResultSet;
        }
    }

    expect:
    !service.checkIfRowExists(1, 2)
}

Hope it will help. These steps are just an orientation to move forward in TDD style. Sure things your reality is different and may require something more specific that I proposed above.

This is perfect. I just needed to know how to go about it. Thanks. — ShadyBears, Jan 06 '19 at 00:41

Spock testing a ResultSet in Groovy

1 Answers1