bug#57905: [PATCH] Fix eshell directory and executable completion on action t

[Daniel Pettersson]

When eshell directory/executable completion results in multiple candidates
the candidates are striped of their file path.

emacs -Q

M-x eshell RET
touch test1 test2
chmod +x test1 test2
./test<Tab>

In *Completions* buffer:
2 possible completions:
test1
test2

Expected:
./test1
./test2

Same issue for directories:

mkdir test_dir1 test_dir2
./test_dir<Tab>

In *Completions* buffer:
2 possible completions:
test1_dir1
test2_dir2

This also the case when the candidates are not in the working directory:
mkdir -p 1/2/3/4
touch 1/2/3/4/test1 1/2/3/4/test2
chmod +x 1/2/3/4/test1 1/2/3/4/test2
./1/2/3/4/test<Tab>

In *Completions* buffer:
2 possible completions:
test1
test2

This issue is not present with one completion as further down the call
stack `completion-file-name-table' is called with action t, which concates
completion string directory with completion candidate.

Possible solution:
---
 lisp/eshell/em-cmpl.el | 29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/lisp/eshell/em-cmpl.el b/lisp/eshell/em-cmpl.el
index 822cc94149..d9261fae27 100644
--- a/lisp/eshell/em-cmpl.el
+++ b/lisp/eshell/em-cmpl.el
@@ -378,6 +378,31 @@ eshell-complete-parse-arguments
        args)
       posns)))

+(defun eshell--pcomplete-executables ()
+  "Complete amongs a list of directories and executables.
+
+Wrapper for `pcomplete-executables' or `pcomplete-dirs-or-entries',
+depending on the value of `eshell-force-execution'.
+
+Adds path prefix to candidates independent of `action' value."
+  ;; `pcomplete-entries' returns filenames without path on `action' t
+  ;; use current string directory as done in `completion-file-name-table'
+  ;; when `action' is nil to construct executable candidates.
+  (let* ((table (if eshell-force-execution
+                    (pcomplete-dirs-or-entries nil #'file-readable-p)
+                  (pcomplete-executables))))
+    (lambda (string pred action)
+      (let ((cands (funcall table string pred action)))
+        (if (eq action t)
+            (let ((specdir (file-name-directory string)))
+              (mapcar
+               (lambda (cand)
+                 (if (stringp cand)
+                     (concat specdir cand)
+                   cand))
+               cands))
+          cands)))))
+
 (defun eshell--complete-commands-list ()
   "Generate list of applicable, visible commands."
   ;; Building the commands list can take quite a while, especially over Tramp
@@ -392,9 +417,7 @@ eshell--complete-commands-list
     (completion-table-dynamic
      (lambda (filename)
        (if (file-name-directory filename)
-           (if eshell-force-execution
-               (pcomplete-dirs-or-entries nil #'file-readable-p)
-             (pcomplete-executables))
+           (eshell--pcomplete-executables)
      (let* ((paths (eshell-get-path))
         (cwd (file-name-as-directory
               (expand-file-name default-directory)))
-- 
2.30.1 (Apple Git-130)


Issue on 28.2.0 as well.

In GNU Emacs 29.0.50 (build 1, aarch64-apple-darwin20.6.0, NS
 appkit-2022.60 Version 11.5.2 (Build 20G95)) of 2022-09-16 built on
 Daniels-Air
Repository revision: fe7c015b20b5bca07aa178d28b9fd5cc66ad16f9
Repository branch: master
Windowing system distributor 'Apple', version 10.3.2022
System Description:  macOS 11.5.2

Configured features:
ACL DBUS GLIB GNUTLS JSON LCMS2 LIBXML2 MODULES NOTIFY KQUEUE NS PDUMPER
PNG RSVG SQLITE3 THREADS TOOLKIT_SCROLL_BARS WEBP XIM ZLIB

Important settings:
  value of $LC_CTYPE: UTF-8
  locale-coding-system: utf-8-unix

Major mode: Eshell

Minor modes in effect:
  shell-dirtrack-mode: t
  eshell-prompt-mode: t
  eshell-hist-mode: t
  eshell-pred-mode: t
  eshell-cmpl-mode: t
  eshell-proc-mode: t
  eshell-arg-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils pcmpl-unix cl-seq
cl-macs vc-git diff-mode easy-mmode vc-dispatcher bug-reference byte-opt
gv bytecomp byte-compile cconv time-date em-unix em-term term disp-table
shell subr-x ehelp em-script em-prompt em-ls em-hist em-pred em-glob
em-extpipe em-cmpl em-dirs esh-var pcomplete comint ansi-color ring
em-basic em-banner em-alias esh-mode eshell esh-cmd generator
cl-loaddefs cl-lib esh-ext esh-opt esh-proc esh-io esh-arg esh-module
esh-groups esh-util rmc iso-transl tooltip eldoc paren electric uniquify
ediff-hook vc-hooks lisp-float-type elisp-mode mwheel term/ns-win ns-win
ucs-normalize mule-util term/common-win tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
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timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer nadvice seq simple cl-generic
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tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs
faces cus-face macroexp files window text-properties overlay sha1 md5
base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads dbusbind kqueue cocoa ns
lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 71482 9836)
 (symbols 48 8490 0)
 (strings 32 24424 2081)
 (string-bytes 1 760661)
 (vectors 16 16661)
 (vector-slots 8 215237 12871)
 (floats 8 32 63)
 (intervals 56 573 57)
 (buffers 1000 13))