[bug#63909] [PATCH v2] home: Add inputrc service.

[Efraim Flashner]

* gnu/home/services/shells.scm (home-inputrc-service-type,
home-inputrc-configuration): New variables.
(serialize-inputrc-key-bindings, serialize-inputrc-variables,
serialize-inputrc-conditional-constructs,
serialize-inputrc-extra-content): New procedures.
* doc/guix.texi (Shells Home Services): Document it.
---
 doc/guix.texi                | 129 +++++++++++++++++++++++++++++++++
 gnu/home/services/shells.scm | 134 ++++++++++++++++++++++++++++++++++-
 2 files changed, 262 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 9232c82b4b..72ab941243 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -42797,6 +42797,135 @@ Shells Home Services
 
 @end deftp
 
+@subsubheading Inputrc Profile Service
+@cindex inputrc
+@cindex readline
+
+The @uref{https://tiswww.cwru.edu/php/chet/readline/rltop.html, GNU
+Readline package} includes Emacs and vi editing modes, with the ability
+to customize the configuration with settings in the @file{~/.inputrc}
+file.  With the @code{gnu home services shells} module, you can setup
+your readline configuration in a predictable manner, as shown below.
+For more information about configuring an @file{~/.inputrc} file,
+@pxref{Readline Init File,,, readline, GNU Readline}.
+
+@defvar home-inputrc-service-type
+
+This is the service to setup various @file{.inputrc} configurations. The
+settings in @file{.inputrc} are read by all programs which are linked
+with GNU Readline.
+
+Here is an example of a service and its configuration that you could add
+to the @code{services} field of your @code{home-environment}:
+
+@lisp
+(service home-inputrc-service-type
+         (home-inputrc-configuration
+           (key-bindings
+            `(("Control-l" . "clear-screen")))
+           (variables
+            `(("bell-style" . "visible")
+              ("colored-completion-prefix" . #t)
+              ("editing-mode" . "vi")
+              ("show-mode-in-prompt" . #t)))
+           (conditional-constructs
+            `(("$if mode=vi" .
+               ,(home-inputrc-configuration
+                  (variables
+                   `(("colored-stats" . #t)
+                     ("enable-bracketed-paste" . #t)))))
+              ("$else" .
+               ,(home-inputrc-configuration
+                  (variables
+                   `(("show-all-if-ambiguous" . #t)))))
+              ("endif" . #t)
+              ("$include" . "/etc/inputrc")
+              ("$include" . ,(file-append
+                               (specification->package "readline")
+                               "/etc/inputrc"))))))
+@end lisp
+
+The example above starts with a combination of @code{key-bindings} and
+@code{variables}.  The @code{conditional-constructs} show how it is
+possible to add conditionals and includes.  In the example above
+@code{colored-stats} is only enabled if the editing mode is @code{vi}
+style, and it also reads any additional configuration located in
+@file{/etc/inputrc} or in @file{/gnu/store/@dots{}-readline/etc/inputrc}.
+
+The value associated with a @code{home-inputrc-service-type} instance
+must be a @code{home-inputrc-configuration} record, as described below.
+
+@end defvar
+
+@anchor{home-inputrc-configuration}
+@deftp {Data Type} home-inputrc-configuration
+Available @code{home-inputrc-configuration} fields are:
+
+@table @asis
+@item @code{key-bindings} (default: @code{'()}) (type: alist)
+Association list of readline key bindings to be added to the
+@file{~/.inputrc} file.
+
+@lisp
+'((\"Control-l\" . \"clear-screen\"))
+@end lisp
+
+turns into
+
+@example
+Control-l: clear-screen
+@end example
+
+@item @code{variables} (default: @code{'()}) (type: alist)
+Association list of readline variables to set.
+
+@lisp
+'((\"bell-style\" . \"visible\")
+  (\"colored-completion-prefix\" . #t))
+@end lisp
+
+turns into
+
+@example
+set bell-style visible
+set colored-completion-prefix on
+@end example
+
+@item @code{conditional-constructs} (default: @code{'()}) (type: alist)
+Association list of conditionals to add to the initialization file.  This
+includes @command{$if}, @command{else}, @command{endif} and @command{include}
+and they receive a value of another @command{home-inputrc-configuration}.
+
+@lisp
+(conditional-constructs
+ `((\"$if mode=vi\" .
+     ,(home-inputrc-configuration
+        (variables
+         `((\"show-mode-in-prompt\" . #t)))))
+   (\"$else\" .
+     ,(home-inputrc-configuration
+        (key-bindings
+         `((\"Control-l\" . \"clear-screen\")))))
+   (\"$endif\" . #t)))
+@end lisp
+
+turns into
+
+@example
+$if mode=vi
+set show-mode-in-prompt on
+$else
+Control-l: clear-screen
+$endif
+@end example
+
+@item @code{extra-content} (default: @code{""}) (type: text-config)
+Extra content appended as-is to the configuration file.  Run @command{man
+readline} for more information about all the configuration options.
+
+@end table
+@end deftp
+
 @node Mcron Home Service
 @subsection Scheduled User's Job Execution
 
diff --git a/gnu/home/services/shells.scm b/gnu/home/services/shells.scm
index f05f2221d6..415b5470c5 100644
--- a/gnu/home/services/shells.scm
+++ b/gnu/home/services/shells.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
 ;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;; Copyright © 2023 Efraim Flashner <efraim@flashner.co.il>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -44,7 +45,10 @@ (define-module (gnu home services shells)
 
             home-fish-service-type
             home-fish-configuration
-            home-fish-extension))
+            home-fish-extension
+
+            home-inputrc-service-type
+            home-inputrc-configuration))
 
 ;;; Commentary:
 ;;;
@@ -626,6 +630,134 @@ (define home-fish-service-type
                 (description "\
 Install and configure Fish, the friendly interactive shell.")))
 
+
+;;;
+;;; Readline.
+;;;
+
+(define (serialize-inputrc-key-bindings field-name val)
+  #~(string-append
+     #$@(map
+         (match-lambda
+           ((key . value)
+            #~(string-append #$key ": " #$value "\n")))
+         val)))
+
+(define (serialize-inputrc-variables field-name val)
+  #~(string-append
+     #$@(map
+         (match-lambda
+           ((key . #f)
+            #~(string-append "set " #$key " off\n"))
+           ((key . #t)
+            #~(string-append "set " #$key " on\n"))
+           ((key . value)
+            #~(string-append "set " #$key " " #$value "\n")))
+         val)))
+
+(define (serialize-inputrc-conditional-constructs field-name val)
+  #~(string-append
+     #$@(map
+         (match-lambda
+           (("$endif" . _)
+            "$endif\n")
+           (("$include" . value)
+            #~(string-append "$include " #$value "\n"))
+           ;; TODO: key can only be "$if" or "$else".
+           ((key . value)
+            #~(string-append #$key "\n"
+                             #$(serialize-configuration
+                                 value
+                                 home-inputrc-configuration-fields))))
+         val)))
+
+(define (serialize-inputrc-extra-content field-name value)
+  #~(if (string=? #$value "") "" (string-append #$value "\n")))
+
+(define-configuration home-inputrc-configuration
+  (key-bindings
+   (alist '())
+   "Association list of readline key bindings to be added to the
+@code{~/.inputrc} file.  This is where code like this:
+
+@lisp
+'((\"Control-l\" . \"clear-screen\"))
+@end lisp
+
+turns into
+
+@example
+Control-l: clear-screen
+@end example"
+   (serializer serialize-inputrc-key-bindings))
+  (variables
+   (alist '())
+   "Association list of readline variables to set.  This is where configuration
+options like this:
+
+@lisp
+'((\"bell-style\" . \"visible\")
+  (\"colored-completion-prefix\" . #t))
+@end lisp
+
+turns into
+
+@example
+set bell-style visible
+set colored-completion-prefix on
+@end example"
+   (serializer serialize-inputrc-variables))
+  (conditional-constructs
+   (alist '())
+   "Association list of conditionals to add to the initialization file.  This
+includes @command{$if}, @command{else}, @command{endif} and @command{include}
+and they receive a value of another @command{home-inputrc-configuration}.
+
+@lisp
+(conditional-constructs
+ `((\"$if mode=vi\" .
+     ,(home-inputrc-configuration
+        (variables
+         `((\"show-mode-in-prompt\" . #t)))))
+   (\"$else\" .
+     ,(home-inputrc-configuration
+        (key-bindings
+         `((\"Control-l\" . \"clear-screen\")))))
+   (\"$endif\" . #t)))
+@end lisp
+
+turns into
+
+@example
+$if mode=vi
+set show-mode-in-prompt on
+$else
+Control-l: clear-screen
+$endif
+@end example"
+   (serializer serialize-inputrc-conditional-constructs))
+  (extra-content
+   (string "")
+   "Extra content appended as-is to the configuration file.  Run @command{man
+readline} for more information about all the configuration options."
+   (serializer serialize-inputrc-extra-content)))
+
+(define (home-inputrc-files config)
+  (list
+   `(".inputrc"
+     ,(mixed-text-file "inputrc"
+                       (serialize-configuration
+                         config
+                         home-inputrc-configuration-fields)))))
+
+(define home-inputrc-service-type
+  (service-type (name 'inputrc)
+                (extensions
+                 (list (service-extension home-files-service-type
+                                          home-inputrc-files)))
+                (default-value (home-inputrc-configuration))
+                (description "Configure readline in @code{.inputrc}.")))
+
 
 (define (generate-home-shell-profile-documentation)
   (generate-documentation

base-commit: e4087930f3ad60918689be5f4bca4ce3e22429f5
-- 
Efraim Flashner   <efraim@flashner.co.il>   רנשלפ םירפא
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