What is the LibGit2Sharp equivalent of git log path?

Question

How do I get a list of commits which contain a particular file, ie the equivalent of git log path for LibGit2Sharp.

Has it not been implemented or is there a way that I'm missing?

Answer 1

I was working on getting the same functionality into my application with LibGit2Sharp.

I wrote the code below which will list all of the commits that contain the file. The GitCommit class isn't included, but it is just a collection of properties.

My intention was to have the code only list commits where the file had changed, similar to a SVN log, but I haven't written that part yet.

Please note that the code hasn't been optimized, it was merely my initial attempt, but I hope it will be useful.

/// <summary>
/// Loads the history for a file
/// </summary>
/// <param name="filePath">Path to file</param>
/// <returns>List of version history</returns>
public List<IVersionHistory> LoadHistory(string filePath)
{
    LibGit2Sharp.Repository repo = new Repository(this.pathToRepo);

    string path = filePath.Replace(this.pathToRepo.Replace(System.IO.Path.DirectorySeparatorChar + ".git", string.Empty), string.Empty).Substring(1);
    List<IVersionHistory> list = new List<IVersionHistory>();

    foreach (Commit commit in repo.Head.Commits)
    {
        if (this.TreeContainsFile(commit.Tree, path) && list.Count(x => x.Date == commit.Author.When) == 0)
        {
            list.Add(new GitCommit() { Author = commit.Author.Name, Date = commit.Author.When, Message = commit.MessageShort} as IVersionHistory);
        }
    }

    return list;
}

/// <summary>
/// Checks a GIT tree to see if a file exists
/// </summary>
/// <param name="tree">The GIT tree</param>
/// <param name="filename">The file name</param>
/// <returns>true if file exists</returns>
private bool TreeContainsFile(Tree tree, string filename)
{
    if (tree.Any(x => x.Path == filename))
    {
        return true;
    }
    else
    {
        foreach (Tree branch in tree.Where(x => x.Type == GitObjectType.Tree).Select(x => x.Target as Tree))
        {
            if (this.TreeContainsFile(branch, filename))
            {
                return true;
            }
        }
    }

    return false;
}

Answer 2

LibGit2Sharp comes from the C library libgit2... which didn't include git log in the first place ;)

Yet, LibGit2Sharp has its own git log function:
Its page on git log involves Filters, but a Filter doesn't seem to filter by path (as detailed in "How to exclude stashes while querying refs?").
So it doesn't seem to be implemented at the moment.

Answer 3

Each time when tree/blob has been changed it gets new id hash. All you need is to compare with parent commit tree/blob item hash:

var commits = repository.Commits
   .Where(c => c.Parents.Count() == 1 && c.Tree["file"] != null &&
      (c.Parents.FirstOrDefault().Tree["file"] == null ||
         c.Tree["file"].Target.Id !=
         c.Parents.FirstOrDefault().Tree["file"].Target.Id));

Answer 4

Very similar to dmck's answer but more up to date

private bool TreeContainsFile(Tree tree, string filePath)
{
    //filePath is the relative path of your file to the root directory
    if (tree.Any(x => x.Path == filePath))
    {
        return true;
    }

    return tree.Where(x => x.GetType() == typeof (TreeEntry))
        .Select(x => x.Target)
        .OfType<Tree>()
        .Any(branch => TreeContainsFile(branch, filePath));
}