home: services: environment-variables: Double-quote values.

Fixes <https://issues.guix.gnu.org/54469>.
Reported by Maxime Devos <maximedevos@telenet.be>.

* gnu/home/services.scm (environment-variable-shell-definitions): New
procedure, with code formerly in 'serialize-posix-env-vars'.
(environment-variables->setup-environment-script): Change
"setup-environment" from 'mixed-text-file' to 'computed-file', and use
'environment-variable-shell-definitions'.
* tests/guix-home.sh: Test it.
* gnu/home/services/shells.scm (serialize-posix-env-vars): Delegate to
'environment-variable-shell-definitions'.

gnu/home/services.scm

@@ -46,6 +46,7 @@
             home-run-on-change-service-type
             home-provenance-service-type
 
+            environment-variable-shell-definitions
             home-files-directory
             xdg-configuration-files-directory
             xdg-data-files-directory
@@ -169,6 +170,34 @@ packages, configuration files, activation script, and so on.")))
 configuration files that the user has declared in their
 @code{home-environment} record.")))
 
+(define (environment-variable-shell-definitions variables)
+  "Return a gexp that evaluates to a list of POSIX shell statements defining
+VARIABLES, a list of environment variable name/value pairs.  The returned code
+ensures variable values are properly quoted."
+  #~(let ((shell-quote
+           (lambda (value)
+             ;; Double-quote VALUE, leaving dollar sign as is.
+             (let ((quoted (list->string
+                            (string-fold-right
+                             (lambda (chr lst)
+                               (case chr
+                                 ((#\" #\\)
+                                  (append (list chr #\\) lst))
+                                 (else (cons chr lst))))
+                             '()
+                             value))))
+               (string-append "\"" quoted "\"")))))
+      (string-append
+       #$@(map (match-lambda
+                 ((key . #f)
+                  "")
+                 ((key . #t)
+                  #~(string-append "export " #$key "\n"))
+                 ((key . value)
+                  #~(string-append "export " #$key "="
+                                   (shell-quote #$value) "\n")))
+               variables))))
+
 (define (environment-variables->setup-environment-script vars)
   "Return a file that can be sourced by a POSIX compliant shell which
 initializes the environment.  The file will source the home
@@ -199,8 +228,11 @@ exported."
     `(("setup-environment"
        ;; TODO: It's necessary to source ~/.guix-profile too
        ;; on foreign distros
-       ,(apply mixed-text-file "setup-environment"
+       ,(computed-file "setup-environment"
-               "\
+                       #~(call-with-output-file #$output
+                           (lambda (port)
+                             (set-port-encoding! port "UTF-8")
+                             (display "\
 HOME_ENVIRONMENT=$HOME/.guix-home
 GUIX_PROFILE=\"$HOME_ENVIRONMENT/profile\"
 PROFILE_FILE=\"$HOME_ENVIRONMENT/profile/etc/profile\"
@@ -227,17 +259,10 @@ case $XCURSOR_PATH in
   *) export XCURSOR_PATH=$HOME_ENVIRONMENT/profile/share/icons:$XCURSOR_PATH ;;
 esac
 
-"
+" port)
-
+                             (display
-               (append-map
+                              #$(environment-variable-shell-definitions vars)
-                (match-lambda
+                              port)))))))))
-                  ((key . #f)
-                   '())
-                  ((key . #t)
-                   (list "export " key "\n"))
-                  ((key . value)
-                   (list "export " key "=" value "\n")))
-                vars)))))))
 
 (define home-environment-variables-service-type
   (service-type (name 'home-environment-variables)

gnu/home/services/shells.scm

@@ -111,30 +111,7 @@ service type can be extended with a list of file-like objects.")))
 
 (define (serialize-boolean field-name val) "")
 (define (serialize-posix-env-vars field-name val)
-  #~(let ((shell-quote
+  (environment-variable-shell-definitions val))
-           (lambda (value)
-             ;; Double-quote VALUE, leaving dollar sign as is.
-             (let ((quoted (list->string
-                            (string-fold-right
-                             (lambda (chr lst)
-                               (case chr
-                                 ((#\" #\\)
-                                  (append (list chr #\\) lst))
-                                 (else (cons chr lst))))
-                             '()
-                             value))))
-               (string-append "\"" quoted "\"")))))
-      (string-append
-       #$@(map
-           (match-lambda
-             ((key . #f)
-              "")
-             ((key . #t)
-              #~(string-append "export " #$key "\n"))
-             ((key . value)
-              #~(string-append "export " #$key "="
-                               (shell-quote #$value) "\n")))
-           val))))
 
 
 ;;;

tests/guix-home.sh

@@ -79,6 +79,10 @@ trap 'chmod -Rf +w "$test_directory"; rm -rf "$test_directory"' EXIT
              (guix-defaults? #t)
              (bashrc (list (local-file "dot-bashrc")))))
 
+   (simple-service 'add-environment-variable
+                   home-environment-variables-service-type
+                   '(("TODAY" . "26 messidor")))
+
    (simple-service 'home-bash-service-extension-test
                    home-bash-service-type
                    (home-bash-extension
@@ -141,6 +145,7 @@ EOF
 # the content of bashrc-test-config.sh"
     grep -q "the content of ~/.config/test.conf" "${HOME}/.config/test.conf"
     grep '^export PS1="\$GUIX_ENVIRONMENT λ "$' "${HOME}/.bash_profile"
+    ( . "${HOME}/.guix-home/setup-environment"; test "$TODAY" = "26 messidor" )
 
     # This one should still be here.
     grep "stay around" "$HOME/.config/random-file"