/// <summary>
/// Calculate for each fix the time between dates when
/// the oldest and the newest buggy code were added.
/// </summary>
/// <param name="bugFixes">Fixes to be processed.</param>
/// <returns>Time in days.</returns>
public static IEnumerable <double> CalculateBugLifetimeSpread(this BugFixSelectionExpression bugFixes)
{
return
((
from bf in bugFixes
join c in bugFixes.Queryable <Commit>() on bf.CommitID equals c.ID
join m in bugFixes.Queryable <Modification>() on c.ID equals m.CommitID
join dcb in bugFixes.Queryable <CodeBlock>() on m.ID equals dcb.ModificationID
join acb in bugFixes.Queryable <CodeBlock>() on dcb.TargetCodeBlockID equals acb.ID
where
dcb.Size < 0
let codeDate = bugFixes.Queryable <Commit>().Single(x => x.ID == acb.AddedInitiallyInCommitID).Date
group codeDate by c.Date into g
select(g.Max() - g.Min()).TotalDays
).ToArray());
}
public static double CalculateStabilizationPeriod(this BugFixSelectionExpression bugFixes, double stabilizationProbability)
{
var bugLifetimes = bugFixes.CalculateAvarageBugLifetime().OrderByDescending(x => x);
int bugLifetimesCount = bugLifetimes.Count();
double stabilizationPeriod = bugLifetimes.First();
foreach (var bugLifetime in bugLifetimes)
{
double lessOrEqualToTotal = (double)bugLifetimes.Where(x => x <= bugLifetime).Count() / bugLifetimes.Count();
if (lessOrEqualToTotal >= stabilizationProbability)
{
stabilizationPeriod = bugLifetime;
}
else
{
break;
}
}
return(stabilizationPeriod);
}
protected override IEnumerable<double> BugLifetimes(BugFixSelectionExpression bugFixes)
{
return bugFixes.CalculateMinBugLifetime();
}
protected virtual IEnumerable<double> BugLifetimes(BugFixSelectionExpression bugFixes)
{
return bugFixes.CalculateAvarageBugLifetime();
}
protected override IEnumerable <double> BugLifetimes(BugFixSelectionExpression bugFixes)
{
return(bugFixes.CalculateMaxBugLifetime());
}
protected virtual IEnumerable <double> BugLifetimes(BugFixSelectionExpression bugFixes)
{
return(bugFixes.CalculateAvarageBugLifetime());
}
