mailmap processing assumes email addresses are valid

[globau]

I've pointed git-of-theseus at https://github.com/mozilla/gecko-dev/, sadly it fails.

First issue: not enough values to unpack in analyze.py:555

mailmap_name, mailmap_email = mail_mapped_author_email[:-1].split(" <", maxsplit=1)

The problem here is gecko-dev has authors without an email address, which end up as an empty author_name in this function; this was easily fixed by:

- pre_mailmap_author_email = f"{author_name} <{author_email}>"
+ pre_mailmap_author_email = f"{author_name or author_email} <{author_email}>"

Second issue: unknown switch 'f' when running git check-mailmap, also triggered at analyze.py:555

Looks there's an author which is just -f. Yeah, I don't know either. mozilla/gecko-dev@1ea9e41
So the command line which ends up running is git check-mailmap -f, which fails. This should be git check-mailmap -- -f.

The easy work-around is to delete the .mailmap file.

[fzakaria]

Here is a commit from LLVM

commit a062856bcf4fca26dab06afdf14bf1c815831f9c
Author: --global <z.zoelec2@gmail.com>
Date:   Mon Oct 28 08:53:44 2019 -0700

    [NFC] Comment endif to test commit access

That also causes it to fail in a "fun" way :P

[fzakaria]

diff --git a/git_of_theseus/analyze.py b/git_of_theseus/analyze.py
index 303cbb0..8492070 100644
--- a/git_of_theseus/analyze.py
+++ b/git_of_theseus/analyze.py
@@ -546,7 +546,7 @@ def analyze(
 
 @functools.lru_cache(maxsize=None)
 def get_mailmap_author_name_email(repo, author_name, author_email):
-    pre_mailmap_author_email = f"{author_name} <{author_email}>"
+    pre_mailmap_author_email = f"{author_name.lstrip('-') if author_name else author_email} <{author_email}>"
     mail_mapped_author_email: str = repo.git.check_mailmap(pre_mailmap_author_email)
     mailmap_name, mailmap_email = mail_mapped_author_email[:-1].split(" <", maxsplit=1)
     return mailmap_name, mailmap_email