hg 5.2.2: abort: Permission denied: '..../.hg/wcache/.manifestfulltextcache-gc3hkx8o~'

[Alan Mackenzie]

Hello, mercurial.

I'm currently running mercurial 5.2.2 on Gentoo GNU/Linux.

On attempting, as a normal user, to apply a tag to a repository, I get
the error message in the subject line.  Both the repository and the
script which applies the tag are many years old, and have usually worked
flawlessly.  I think the change to the latest version of hg coincided
with the appearance of this error message.

..../.hg/wcache looks like this:

drwxr-xr-x 2 root root 4096 Apr 26  2019 .hg/wcache/

, and the contents of ..../.hg/wcache look like this:

-rwx--x--x 1 root root  0 Mar 22  2019 checkisexec
lrwxrwxrwx 1 root root 16 Apr 26  2019 checklink -> checklink-target
-rw-r--r-- 1 root root  0 Apr 26  2019 checklink-target
-rw-r--r-- 1 root root  0 Mar 29  2019 checknoexec

.  It seems strange that this directory and its contents are owned by
root.  It seems an altogether strange directory in any case.

What is going on here that produces this error message?

Please help me get this repository working again.  Thanks!

-- 
Alan Mackenzie (Nuremberg, Germany).