We actually ran rustfmt, but it's an older version (rustfmt 1.3.0-stable (d334502 2019-06-09)) and I verified the code still formats under that particular version of rustfmt with empty rustfmt.toml. In other words, rustfmt itself seems to change over time.

Thank you for the feedback, @quark! You enlightened me to a few issues I missed during my very quick perusal.

No longer use this approach.

No longer use this approach.

Took another approach.

No longer needed.

if listsubrepos:
    for subpath in ctx.substate:

• sm = ctx.sub(subpath).matchfileset(pat, badfn=badfn)

+ sm = ctx.sub(subpath).matchfileset(
+ pat, badfn=badfn, cwd=cwd
+ )

When the environment is empty (specifically: it doesn't contain LC_ALL,
LC_CTYPE, or LANG), Python will "coerce" the locale environment variables to be
a UTF-8 capable one. It sets LC_CTYPE in the environment, and this breaks chg,
since chg operates by:
- start hg, using whatever environment the user has when chg starts
- hg stores a hash of this "original" environment, but python has already set LC_CTYPE even though the user doesn't have it in their environment
- chg calls setenv over the commandserver. This clears the environment inside of hg and sets it to be exactly what the environment in chg is (without LC_CTYPE).
- chg calls validate to ensure that the environment hg is using (after the setenv call) is the one that the chg process has - if not, it is assumed the user changed their environment and we should use a different server. This will *never* be true in this situation because LC_CTYPE was removed.

CC: @martinvonz

It said revision before, so at a minimum we should add an s...

Isn't it that where ever we says revisions we imply revsets?

Looks like I forgot to drop this from my queue and pushed it. :(