public void GivenPeople_ThenFormattedPeopleWrittenToFile()
{
// Arrange
var people = new[]
{
new Person("AFirst", "ALast"),
new Person("BFirst", "BLast")
};
var formatter = Substitute.For<IPersonFormatter>();
formatter.FormatPerson(people[0]).Returns("ALast, AFirst");
formatter.FormatPerson(people[1]).Returns("BLast, BFirst");
var fileWriter = Substitute.For<IFileWriter>();
// Act
var displayer = new PeopleDisplayerToFile(formatter, fileWriter);
displayer.DisplayPeople(people);
// Assert
var verifyDataCallback = new Func<IEnumerable<string>, bool>(data =>
{
var dataList = data.ToList();
return dataList.Count == 2
&& dataList[0] == "ALast, AFirst"
&& dataList[1] == "BLast, BFirst";
});
fileWriter.Received().WriteData(
Arg.Is<IEnumerable<string>>(data => verifyDataCallback(data)));
}
public void GivenNoPeople_ThenNoPeopleWrittenToFile()
{
// Arrange
var formatter = Substitute.For<IPersonFormatter>();
var fileWriter = Substitute.For<IFileWriter>();
// Act
var displayer = new PeopleDisplayerToFile(formatter, fileWriter);
displayer.DisplayPeople(new Person[0]);
// Assert
fileWriter.Received().WriteData(
Arg.Is<IEnumerable<string>>(data => !data.Any()));
}