public virtual Differences VisitQueryAlias(QueryAlias alias1, QueryAlias alias2){
Differences differences = new Differences(alias1, alias2);
if (alias1 == null || alias2 == null){
if (alias1 != alias2) differences.NumberOfDifferences++; else differences.NumberOfSimilarities++;
return differences;
}
QueryAlias changes = (QueryAlias)alias2.Clone();
QueryAlias deletions = (QueryAlias)alias2.Clone();
QueryAlias insertions = (QueryAlias)alias2.Clone();
Differences diff = this.VisitExpression(alias1.Expression, alias2.Expression);
if (diff == null){Debug.Assert(false); return differences;}
changes.Expression = diff.Changes as Expression;
deletions.Expression = diff.Deletions as Expression;
insertions.Expression = diff.Insertions as Expression;
Debug.Assert(diff.Changes == changes.Expression && diff.Deletions == deletions.Expression && diff.Insertions == insertions.Expression);
differences.NumberOfDifferences += diff.NumberOfDifferences;
differences.NumberOfSimilarities += diff.NumberOfSimilarities;
diff = this.VisitIdentifier(alias1.Name, alias2.Name);
if (diff == null){Debug.Assert(false); return differences;}
changes.Name = diff.Changes as Identifier;
deletions.Name = diff.Deletions as Identifier;
insertions.Name = diff.Insertions as Identifier;
Debug.Assert(diff.Changes == changes.Name && diff.Deletions == deletions.Name && diff.Insertions == insertions.Name);
differences.NumberOfDifferences += diff.NumberOfDifferences;
differences.NumberOfSimilarities += diff.NumberOfSimilarities;
if (differences.NumberOfDifferences == 0){
differences.Changes = null;
differences.Deletions = null;
differences.Insertions = null;
}else{
differences.Changes = changes;
differences.Deletions = deletions;
differences.Insertions = insertions;
}
return differences;
}
public override Node VisitQueryAlias(QueryAlias alias){
if (alias == null) return null;
return base.VisitQueryAlias((QueryAlias)alias.Clone());
}