Subject: 27.1; (describe-variable) breaks eshell

From: [email-masked]
Date: Sat, 03 Oct 2020 02:11:43 +0000

When using eshell-mode, calling `(describe-variable)` on a variable that
starts with "eshell" causes eshell-watch-for-password-prompt to no
longer function correctly.  In the attached dribble file, I first show
the correct behavior by opening eshell and entering `sudo ls`; eshell
correctly prompts me for a password three times.  I then run
`(describe-variable 'eshell-after-prompt-hook)` and then enter `sudo
ls`.  This time, eshell displays the incorrect behavior: it prints the
string "password" but does not accept input as a password or print any
output from the command.  I selected `eshell-after-prompt-hook` becuase
it is one of the first variables starting with "eshell", but the same
behavior occurs with other variables, including user-defined ones.

The information below, generated with report-emacs-bug, is for my
laptop, where I observed the above bug on Emacs 27.1.  I also observed
the same bug on my desktop on Emacs 26.3 (build 2, x86_64-pc-linux-gnu),
so the issue isn't specific to the Void musl build.

I hope this information is helpful.  Thank you all for the wonderful
work you do on Emacs, and please let me know if I can provide any other
information.

Best regards,
Daniel 

In GNU Emacs 27.1 (build 1, x86_64-unknown-linux-musl)
 of 2020-08-12 built on vm1-a-mci-us
System Description: void

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Making completion list... [3 times]

Configured using:
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Memory information:
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