List_Traverse_Tests.java

package fj.data;

import fj.F;
import org.junit.Assert;
import org.junit.Test;

import static fj.data.List.list;
import static fj.data.Option.some;
import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assert.assertThat;

/**
 * Created by amar on 28/12/14.
 */
public class List_Traverse_Tests {

    @Test
    public void shouldTraverseListWithGivenFunction(){
        List<String> strings = list("some1", "some2", "some3", "not_some", "  ");
        F<String, Option<String>> f = s -> {
            if(s.startsWith("some"))
                return some(s);
            else
                return Option.none();
        };

        Option<List<String>> optStr = strings.traverseOption(f);
        Assert.assertEquals("optStr should be none", Option.none(), optStr);
    }

    @Test
    public void shouldTraverseListWithGivenFunction2(){
        List<String> strings = list("some1", "some2", "some3");
        F<String, Option<String>> f = s -> {
            if(s.startsWith("some"))
                return some(s);
            else
                return Option.none();
        };

        Option<List<String>> optStr = strings.traverseOption(f);
        Assert.assertEquals("optStr should be some", optStr.isSome(), true);
        assertThat(optStr.some(), is(List.list("some1", "some2", "some3")));
    }

}