/// <summary>
/// Create an iterator to walk the merge base of two commits.
/// </summary>
/// <param name="aIdx">
/// Index of the first commit in <seealso cref="SourceObjects"/>.
/// </param>
/// <param name="bIdx">
/// Index of the second commit in <seealso cref="SourceObjects"/>.
/// </param>
/// <returns> the new iterator </returns>
/// <exception cref="IncorrectObjectTypeException">
/// one of the input objects is not a commit.
/// </exception>
/// <exception cref="IOException">
/// objects are missing or multiple merge bases were found.
/// </exception>
protected AbstractTreeIterator MergeBase(int aIdx, int bIdx)
{
if (_sourceCommits[aIdx] == null)
{
throw new IncorrectObjectTypeException(_sourceObjects[aIdx], Constants.TYPE_COMMIT);
}
if (_sourceCommits[bIdx] == null)
{
throw new IncorrectObjectTypeException(_sourceObjects[bIdx], Constants.TYPE_COMMIT);
}
_walk.reset();
_walk.setRevFilter(RevFilter.MERGE_BASE);
_walk.markStart(_sourceCommits[aIdx]);
_walk.markStart(_sourceCommits[bIdx]);
RevCommit base1 = _walk.next();
if (base1 == null)
{
return(new EmptyTreeIterator());
}
RevCommit base2 = _walk.next();
if (base2 != null)
{
throw new IOException("Multiple merge bases for:" + "\n "
+ _sourceCommits[aIdx].Name + "\n "
+ _sourceCommits[bIdx].Name + "found:" + "\n "
+ base1.Name + "\n " + base2.Name);
}
return(OpenTree(base1.Tree));
}