GitVersion.VersionCalculation.NextVersionCalculator.FindMainlineModeVersion C# (CSharp) Method

        SemanticVersion FindMainlineModeVersion(BaseVersion baseVersion, GitVersionContext context)
        {
            if (baseVersion.SemanticVersion.PreReleaseTag.HasTag())
            {
                throw new NotSupportedException("Mainline development mode doesn't yet support pre-release tags on master");
            }

            using (Logger.IndentLog("Using mainline development mode to calculate current version"))
            {
                var mainlineVersion = baseVersion.SemanticVersion;

                // Forward merge / PR
                //          * feature/foo
                //         / |
                // master *  *
                //
                var commitLog = context.Repository.Commits.QueryBy(new CommitFilter
                {
                    IncludeReachableFrom = context.CurrentBranch,
                    ExcludeReachableFrom = baseVersion.BaseVersionSource,
                    SortBy = CommitSortStrategies.Reverse,
                    FirstParentOnly = true
                }).Where(c => c.Sha != baseVersion.BaseVersionSource.Sha).ToList();

                var directCommits = new List<Commit>();

                // Scans commit log in reverse, aggregating merge commits
                foreach (var commit in commitLog)
                {
                    directCommits.Add(commit);
                    if (commit.Parents.Count() > 1)
                    {
                        mainlineVersion = AggregateMergeCommitIncrement(context, commit, directCommits, mainlineVersion);
                    }
                }

                if (context.CurrentBranch.FriendlyName != "master")
                {
                    var mergedHead = context.CurrentCommit;
                    var mainlineTip = GetMainlineTip(context);
                    var findMergeBase = context.Repository.ObjectDatabase.FindMergeBase(context.CurrentCommit, mainlineTip);
                    Logger.WriteInfo(string.Format("Current branch ({0}) was branch from {1}", context.CurrentBranch.FriendlyName, findMergeBase));

                    var branchIncrement = FindMessageIncrement(context, null, mergedHead, findMergeBase, directCommits);
                    // This will increment for any direct commits on master
                    mainlineVersion = IncrementForEachCommit(context, directCommits, mainlineVersion);
                    mainlineVersion.BuildMetaData = metaDataCalculator.Create(findMergeBase, context);
                    // Only increment if head is not a merge commit, ensures PR's and forward merges end up correct.
                    if (mergedHead.Parents.Count() == 1)
                    {
                        Logger.WriteInfo(string.Format("Performing {0} increment for current branch ", branchIncrement));
                        mainlineVersion = mainlineVersion.IncrementVersion(branchIncrement);
                    }
                }
                else
                {
                    // If we are on master, make sure no commits get left behind
                    mainlineVersion = IncrementForEachCommit(context, directCommits, mainlineVersion);
                    mainlineVersion.BuildMetaData = metaDataCalculator.Create(baseVersion.BaseVersionSource, context);
                }

                return mainlineVersion;
            }
        }