/// <summary>
/// Generates Diff results for each change that occurred from the ancestor to the changed
/// </summary>
/// <param name="ancestor">
/// The abstract syntax tree that the changed version originated from
/// </param>
/// <param name="changed">The abstract syntax tree that resulted from changing the ancestor</param>
/// <returns>Changes between the ancestor and changed</returns>
public static IEnumerable <Diff> Compare(SyntaxTree ancestor, SyntaxTree changed)
{
var offset = 0; //Tracks differences in indexes moving through the changed syntax tree
foreach (var change in changed.GetChanges(ancestor))
{ //Assumes that this list is sorted by place in file
var origLength = change.Span.Length;
var offsetChange = (change.NewText.Length - origLength);
var chanStart = change.Span.Start + offset;
var chanLength = origLength + offsetChange;
offset += offsetChange;
var d = new Diff
{
Ancestor = SpanDetails.Create(change.Span, ancestor),
Changed = SpanDetails.Create(new TextSpan(chanStart, chanLength), changed)
};
yield return(d);
}
}
internal static Conflict Create(List <DiffWithOrigin> potentialConflict, SyntaxTree ancestorTree, SyntaxTree localTree, SyntaxTree remoteTree)
{
var fllocal = FindStartEnd(potentialConflict.Where(c => c.Origin == DiffWithOrigin.OriginEnum.Local).Select(c => c.Diff));
var flremote = FindStartEnd(potentialConflict.Where(c => c.Origin == DiffWithOrigin.OriginEnum.Remote).Select(c => c.Diff));
var localStartOffset = fllocal.Item1.OffsetStart;
var localEndOffset = fllocal.Item2.OffsetEnd;
var remoteStartOffset = flremote.Item1.OffsetStart;
var remoteEndOffset = flremote.Item2.OffsetEnd;
var first = MinAncestorStart(fllocal.Item1, flremote.Item1).Ancestor.Span.Start;
var last = MaxAncestorEnd(fllocal.Item2, flremote.Item2).Ancestor.Span.End;
var con = new Conflict
{
Ancestor = SpanDetails.Create(first, last, ancestorTree),
Local = SpanDetails.Create(first + localStartOffset, last + localEndOffset, localTree),
Remote = SpanDetails.Create(first + remoteStartOffset, last + remoteEndOffset, remoteTree)
};
return(con);
}