GitVersion.GitVersionContext.GitVersionContext C# (CSharp) Method

        public GitVersionContext(IRepository repository, Branch currentBranch, Config configuration, bool onlyEvaluateTrackedBranches = true, string commitId = null)
        {
            Repository = repository;
            RepositoryMetadataProvider = new GitRepoMetadataProvider(repository);
            FullConfiguration = configuration;
            OnlyEvaluateTrackedBranches = onlyEvaluateTrackedBranches;

            if (currentBranch == null)
                throw new InvalidOperationException("Need a branch to operate on");

            if (!string.IsNullOrWhiteSpace(commitId))
            {
                Logger.WriteInfo(string.Format("Searching for specific commit '{0}'", commitId));

                var commit = repository.Commits.FirstOrDefault(c => string.Equals(c.Sha, commitId, StringComparison.OrdinalIgnoreCase));
                if (commit != null)
                {
                    CurrentCommit = commit;
                }
                else
                {
                    Logger.WriteWarning(string.Format("Commit '{0}' specified but not found", commitId));
                }
            }

            if (CurrentCommit == null)
            {
                Logger.WriteInfo("Using latest commit on specified branch");
                CurrentCommit = currentBranch.Tip;
            }

            if (currentBranch.IsDetachedHead())
            {
                CurrentBranch = RepositoryMetadataProvider.GetBranchesContainingCommit(CurrentCommit, repository.Branches.ToList(), OnlyEvaluateTrackedBranches).OnlyOrDefault() ?? currentBranch;
            }
            else
            {
                CurrentBranch = currentBranch;
            }

            CalculateEffectiveConfiguration();

            CurrentCommitTaggedVersion = repository.Tags
                .SelectMany(t =>
                {
                    SemanticVersion version;
                    if (t.PeeledTarget() == CurrentCommit && SemanticVersion.TryParse(t.FriendlyName, Configuration.GitTagPrefix, out version))
                        return new[] { version };
                    return new SemanticVersion[0];
                })
                .Max();
            IsCurrentCommitTagged = CurrentCommitTaggedVersion != null;
        }