bug#37229: EasyPG selects revoked key, rather than the obvious current one as recipient on file save

[Beto HydroxyButyrate]

I have a test file named Test1.gpg with the following at the top:
;; -*- epa-file-encrypt-to: ("beto@zepherin.com") -*-

I write out the file. It throws this error:

Debugger entered--Lisp error: (file-error "Opening output file" "Encrypt
failed" "Unusable public key: 4253BDD3FF52DC13; Exit")
signal(file-error ("Opening output file" "Encrypt failed" "Unusable
public key: 4253BDD3FF52DC13; Exit"))
epa-file-write-region(nil nil "/home/user/Documents/Auth/Test1.gpg" nil
t "~/Documents/Auth/Test1.gpg" nil)
apply(epa-file-write-region (nil nil
"/home/user/Documents/Auth/Test1.gpg" nil t "~/Documents/Auth/Test1.gpg"
nil))
epa-file-handler(write-region nil nil
"/home/user/Documents/Auth/Test1.gpg" nil t "~/Documents/Auth/Test1.gpg"
nil)
write-region(nil nil "/home/user/Documents/Auth/Test1.gpg" nil t
"~/Documents/Auth/Test1.gpg")
basic-save-buffer-2()
basic-save-buffer-1()
basic-save-buffer(t)
save-buffer(1)
funcall-interactively(save-buffer 1)
call-interactively(save-buffer nil nil)
command-execute(save-buffer)

The problem is that EasyPG selects the revoked key. The solution is
*not* to delete the revoked key from my keyring. I need the revoked key
to be able to decode email previously sent encrypted using this revoked
key.
I did some googling and saw that there have been at least two other
reports of this issue, but someone hacked up a kluge specifically for
email, rather than fixing the general case.



In GNU Emacs 26.1 (build 1, x86_64-redhat-linux-gnu, GTK+ Version 3.23.2)
of 2018-08-13 built on buildvm-13.phx2.fedoraproject.org
Windowing system distributor 'Fedora Project', version 11.0.12004000
System Description: Fedora release 29 (Twenty Nine)

Recent messages:
<<< Type SPC or RET to bury the buffer list >>>
Saving file /home/user/Documents/Auth/Test1.gpg...
epa-file-write-region: Opening output file: Encrypt failed, Unusable
public key: 4253BDD3FF52DC13; Exit
<<< Type SPC or RET to bury the buffer list >>>
Mark set
t [2 times]
<<< Type SPC or RET to bury the buffer list >>>
Saving file /home/user/Documents/Auth/Test1.gpg...
Entering debugger...
<<< Type SPC or RET to bury the buffer list >>>

Configured using:
'configure --build=x86_64-redhat-linux-gnu
--host=x86_64-redhat-linux-gnu --program-prefix=
--disable-dependency-tracking --prefix=/usr --exec-prefix=/usr
--bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc
--datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib64
--libexecdir=/usr/libexec --localstatedir=/var
--sharedstatedir=/var/lib --mandir=/usr/share/man
--infodir=/usr/share/info --with-dbus --with-gif --with-jpeg --with-png
--with-rsvg --with-tiff --with-xft --with-xpm --with-x-toolkit=gtk3
--with-gpm=no --with-xwidgets --with-modules
build_alias=x86_64-redhat-linux-gnu host_alias=x86_64-redhat-linux-gnu
'CFLAGS=-DMAIL_USE_LOCKF -O2 -g -pipe -Wall -Werror=format-security
-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions
-fstack-protector-strong -grecord-gcc-switches
-specs=/usr/lib/rpm/redhat/redhat-hardened-cc1
-specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic
-fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection'
LDFLAGS=-Wl,-z,relro
PKG_CONFIG_PATH=:/usr/lib64/pkgconfig:/usr/share/pkgconfig'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND DBUS GSETTINGS NOTIFY ACL
LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 MODULES THREADS XWIDGETS LCMS2

Important settings:
value of $LANG: C.UTF-8
locale-coding-system: utf-8-unix

Major mode: Debugger

Minor modes in effect:
shell-dirtrack-mode: t
show-paren-mode: t
display-time-mode: t
minibuffer-electric-default-mode: t
tooltip-mode: t
global-eldoc-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
font-lock-mode: t
blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
buffer-read-only: t
line-number-mode: t
transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny format-spec rfc822 mml
mml-sec password-cache gnus-util rmail rmail-loaddefs mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
cl-print debug cl-extra help-fns radix-tree help-mode misearch
multi-isearch shell pcomplete epa-file epa derived epg epg-config
image-mode rng-xsd xsd-regexp rng-cmpct rng-nxml rng-valid rng-loc
rng-uri rng-parse nxml-parse rng-match rng-dt rng-util rng-pttrn nxml-ns
nxml-mode nxml-outln nxml-rap sgml-mode seq byte-opt gv bytecomp
byte-compile cconv dom nxml-util nxml-enc xmltok view dired
dired-loaddefs elec-pair cus-edit cus-start cus-load wid-edit paren time
minibuf-eldef ruby-mode smie cc-mode cc-fonts cc-guess cc-menus cc-cmds
cc-styles cc-align cc-engine cc-vars cc-defs compile info easymenu ehelp
echistory chistory ebuff-menu hippie-exp comint ansi-color ring edmacro
kmacro cl-loaddefs cl-lib ls-lisp time-date mule-util tooltip eldoc
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel term/x-win
x-win term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow isearch timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame cl-generic cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite charscript charprop case-table epa-hook jka-cmpr-hook
help simple abbrev obarray minibuffer cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote dbusbind inotify lcms2 dynamic-setting system-font-setting
font-render-setting xwidget-internal move-toolbar gtk x-toolkit x
multi-tty make-network-process emacs)

Memory information:
((conses 16 174725 10251)
(symbols 48 27705 1)
(miscs 40 367 292)
(strings 32 50902 1271)
(string-bytes 1 1474559)
(vectors 16 22946)
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