[PATCH 0/1] Hashed mailmap support

Many people, through the course of their lives, will change either a name or an email address. For this reason, we have the mailmap, to map from a user's former name or email address to their current, canonical forms. Normally, this works well as it is.

However, sometimes people change a name (or an email) and want to completely cease use of the former name or email. This could be because a transgender person has transitioned, because a person has left an abusive partner or broken ties with an abusive family member, or for any other number of good and valuable reasons. In these cases, placing the former name in the .mailmap may be undesirable.

For those situations, let's introduce a hashed mailmap, where the user's former name or email address can be in the form @sha256:<hash>. This obscures the former name or email.

Note that this is not perfect, because a user can simply look up all the hashed values and find out the old values. However, for projects which wish to adopt the feature, it can be somewhat effective to hash all existing mailmap entries and include some no-op entries from other contributors as well, so as to make this process less convenient.

I've spoken to a variety of folks about this, and while we all agree this design isn't perfect, it is an improvement over the status quo. It is obfuscation, not security, and in this case, I think that's fine. I'm open to hearing ideas about how to improve this design if there are any.

I welcome feedback on this patch, while encouraging people to be mindful of our code of conduct.

brian m. carlson (1):
  mailmap: support hashed entries in mailmaps

 mailmap.c          | 39 +++++++++++++++++++++++++++++++++++++--
 t/t4203-mailmap.sh | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 2 deletions(-)