public void DataComparerTest(string x, string y, int expected)
{
var dataComparer = new StringDataItemComparer();
var actual = dataComparer.Compare(x, y);
Assert.AreEqual(expected, actual);
}
public static void MergeFiles(string source1, string source2, string destination)
{
using var reader1 = new StreamReader(source1);
using var reader2 = new StreamReader(source2);
using var writer = new StreamWriter(destination);
using var iterator1 = ToIterator(reader1);
using var iterator2 = ToIterator(reader2);
var iterator1StillAvailable = iterator1.MoveNext();
var iterator2StillAvailable = iterator2.MoveNext();
while (iterator1StillAvailable && iterator2StillAvailable)
{
if (Comparer.Compare(iterator1.Current, iterator2.Current) <= 0)
{
writer.WriteLine(iterator1.Current);
iterator1StillAvailable = iterator1.MoveNext();
}
else
{
writer.WriteLine(iterator2.Current);
iterator2StillAvailable = iterator2.MoveNext();
}
}
//check which iterator can still provide values
var iteratorRemaining = iterator1StillAvailable
? iterator1
: iterator2StillAvailable ? iterator2 : null;
if (null != iteratorRemaining)
{
do
{
writer.WriteLine(iteratorRemaining.Current);
} while (iteratorRemaining.MoveNext());
}
}
