/// <summary>
/// Gets a single result from the reader.
/// </summary>
public static TEntity Single <TEntity, TKey>(this ILinqReader <TEntity, TKey> reader)
where TEntity : class
{
Guard.ArgumentNotNull(reader, nameof(reader));
return(reader.Single(_ => true));
}
/// <summary>
/// Gets the first element in a given reader.
/// </summary>
public static T First <T, K>(this ILinqReader <T, K> reader)
where T : class
{
Guard.ArgumentNotNull(reader, nameof(reader));
return(reader.First(_ => true));
}
/// <summary>
/// Gets a single result from a linq reader.
/// </summary>
public static TEntity Single <TEntity, TKey>(this ILinqReader <TEntity, TKey> reader,
Expression <Func <TEntity, bool> > predicate)
where TEntity : class
{
Guard.ArgumentNotNull(reader, nameof(reader));
Guard.ArgumentNotNull(predicate, nameof(predicate));
var item = reader.SingleOrDefault(predicate);
if (item == null)
{
throw new InvalidOperationException("No element satisfies the condition in predicate.");
}
return(item);
}
protected void GivenALinqReaderWithData()
{
var repo = new InMemoryRepository <TestEntity, Guid>();
_reader = repo;
// insert
repo.Insert(new TestEntity
{
Id = Guid.NewGuid(),
Name = "Name"
});
repo.Insert(new TestEntity
{
Id = Guid.NewGuid(),
Name = "Name 2"
});
}
