[bug#50873] [PATCH v3 1/8] guix home: import: Make the user to specify a destination directory.

[Xinglu Chen <public@yoctocell.xyz>]

Copy the appropriate the relevant configuration files to the destination
directory, and call ‘local-file’ on them.

Without this, ‘guix home import’ will generate a service declaration like this

  (service
   home-bash-service-type
   (home-bash-configuration
    (bashrc
     (list (slurp-file-gexp
            (local-file "/home/yoctocell/.bashrc"))))))

but when running ‘guix home reconfigure’, the ~/.bashrc file would be moved, so
when running ‘guix home reconfigure’ for the second time, it would read the
~/.bashrc which is itself a symlink to a file the store.

* guix/scripts/home/import.scm (generate-bash-module+configuration): Take
‘destination-directory’ parameter
(modules+configurations): Copy the user’s configuration file to
‘%destination-directory’.
* guix/scripts/home.scm (process-command): Adjust accordingly; create
‘destination’ if it doesn’t exist.
---
 guix/scripts/home.scm        | 24 ++++++----
 guix/scripts/home/import.scm | 86 +++++++++++++++++++++---------------
 2 files changed, 65 insertions(+), 45 deletions(-)

diff --git a/guix/scripts/home.scm b/guix/scripts/home.scm
index 55e7b436c1..3f48b98ed4 100644
--- a/guix/scripts/home.scm
+++ b/guix/scripts/home.scm
@@ -40,6 +40,7 @@ (define-module (guix scripts home)
   #:autoload   (guix scripts pull) (channel-commit-hyperlink)
   #:use-module (guix scripts home import)
   #:use-module ((guix status) #:select (with-status-verbosity))
+  #:use-module ((guix build utils) #:select (mkdir-p))
   #:use-module (guix gexp)
   #:use-module (guix monads)
   #:use-module (srfi srfi-1)
@@ -260,15 +261,20 @@ (define-syntax-rule (with-store* store exp ...)
      (apply search args))
     ((import)
      (let* ((profiles (delete-duplicates
-                      (match (filter-map (match-lambda
-                                           (('profile . p) p)
-                                           (_              #f))
-                                         opts)
-                        (() (list %current-profile))
-                        (lst (reverse lst)))))
-           (manifest (concatenate-manifests
-                      (map profile-manifest profiles))))
-       (import-manifest manifest (current-output-port))))
+                       (match (filter-map (match-lambda
+                                            (('profile . p) p)
+                                            (_              #f))
+                                          opts)
+                         (() (list %current-profile))
+                         (lst (reverse lst)))))
+            (manifest (concatenate-manifests
+                       (map profile-manifest profiles)))
+            (destination (match args
+                           ((destination) destination)
+                           (_ (leave (G_ "wrong number of arguments~%"))))))
+       (unless (file-exists? destination)
+         (mkdir-p destination))
+       (import-manifest manifest destination (current-output-port))))
     ((describe)
      (match (generation-number %guix-home)
        (0
diff --git a/guix/scripts/home/import.scm b/guix/scripts/home/import.scm
index 611f580e85..c7c60e95e8 100644
--- a/guix/scripts/home/import.scm
+++ b/guix/scripts/home/import.scm
@@ -36,49 +36,61 @@ (define-module (guix scripts home import)
 ;;;
 ;;; Code:
 
+(define (generate-bash-configuration+modules destination-directory)
+  (define (destination-append path)
+    (string-append destination-directory "/" path))
 
-(define (generate-bash-module+configuration)
-  (let ((rc (string-append (getenv "HOME") "/.bashrc"))
-        (profile (string-append (getenv "HOME") "/.bash_profile"))
-        (logout (string-append (getenv "HOME") "/.bash_logout")))
-    `((gnu home services bash)
+  (let ((rc (destination-append ".bashrc"))
+        (profile (destination-append ".bash_profile"))
+        (logout (destination-append ".bash_logout")))
+    `((gnu home-services bash)
       (service home-bash-service-type
-                 (home-bash-configuration
-                  ,@(if (file-exists? rc)
-                        `((bashrc
-                           (list (local-file ,rc))))
-                        '())
-                  ,@(if (file-exists? profile)
-                        `((bash-profile
-                           (list (local-file ,profile))))
-                        '())
-                  ,@(if (file-exists? logout)
-                        `((bash-logout
-                           (list (local-file ,logout))))
-                        '()))))))
-
+               (home-bash-configuration
+                ,@(if (file-exists? rc)
+                      `((bashrc
+                         (list (slurp-file-gexp
+                                (local-file ,rc)))))
+                      '())
+                ,@(if (file-exists? profile)
+                      `((bash-profile
+                         (list (slurp-file-gexp
+                                (local-file ,profile)))))
+                      '())
+                ,@(if (file-exists? logout)
+                      `((bash-logout
+                         (list (slurp-file-gexp
+                                (local-file ,logout)))))
+                      '()))))))
 
 (define %files-configurations-alist
   `((".bashrc" . ,generate-bash-module+configuration)
     (".bash_profile" . ,generate-bash-module+configuration)
     (".bash_logout" . ,generate-bash-module+configuration)))
 
-(define (modules+configurations)
-  (let ((configurations (delete-duplicates
-                         (filter-map (match-lambda
-                                ((file . proc)
-                                 (if (file-exists?
-                                      (string-append (getenv "HOME") "/" file))
-                                     proc
-                                     #f)))
-                                     %files-configurations-alist)
-                         (lambda (x y)
-                           (equal? (procedure-name x) (procedure-name y))))))
-    (map (lambda (proc) (proc)) configurations)))
+(define (configurations+modules destination-directory)
+  "Return a list of procedures which when called, generate code for a home
+service declaration."
+  (define configurations
+    (delete-duplicates
+     (filter-map (match-lambda
+                   ((file . proc)
+                    (let ((absolute-path (string-append (getenv "HOME")
+                                                        "/" file)))
+                      (and (file-exists? absolute-path)
+                           (begin
+                             (copy-file absolute-path
+                                        (string-append
+                                         destination-directory "/" file))
+                             proc)))))
+                 %files+configurations-alist)
+     (lambda (x y)
+       (equal? (procedure-name x) (procedure-name y)))))
+  
+  (map (lambda (proc) (proc destination-directory)) configurations))
 
 ;; Based on `manifest->code' from (guix profiles)
 ;; MAYBE: Upstream it?
-(define* (manifest->code manifest
+(define* (manifest->code manifest destination-directory
                          #:key
                          (entry-package-version (const ""))
                          (home-environment? #f))
@@ -129,7 +141,8 @@ (define (qualified-name entry)
                                                    ":" output))))
                         (manifest-entries manifest))))
         (if home-environment?
-            (let ((modules+configurations (modules+configurations)))
+            (let ((configurations+modules
+                   (configurations+modules destination-directory)))
               `(begin
                (use-modules (gnu home)
                             (gnu packages)
@@ -171,7 +184,8 @@ (define name
                              (options->transformation ',options))))
                        transformation-procedures)))
         (if home-environment?
-            (let ((modules+configurations (modules+configurations)))
+            (let ((configurations+modules
+                   (configurations+modules destination-directory)))
               `(begin
                  (use-modules (guix transformations)
                               (gnu home)
@@ -204,7 +218,7 @@ (define* (home-environment-template #:key (packages #f) (specs #f) services)
      (services (list ,@services))))
 
 (define* (import-manifest
-          manifest
+          manifest destination-directory
           #:optional (port (current-output-port)))
   "Write to PORT a <home-environment> corresponding to MANIFEST."
   (define (version-spec entry)
@@ -227,7 +241,7 @@ (define (version-spec entry)
                (version-unique-prefix (manifest-entry-version entry)
                                       versions)))))))
 
-  (match (manifest->code manifest
+  (match (manifest->code manifest destination-directory
                          #:entry-package-version version-spec
                          #:home-environment? #t)
     (('begin exp ...)
-- 
2.33.0