accounts: Add default value for the 'home-directory' field of <user-account>.

* gnu/system/accounts.scm (<user-account>)[home-directory]: Mark as
thunked and add a default value.
(default-home-directory): New procedure.
* doc/guix.texi (User Accounts): Remove 'home-directory' from example.
* gnu/system/examples/bare-bones.tmpl: Likewise.
* gnu/system/examples/beaglebone-black.tmpl: Likewise.
* gnu/system/examples/desktop.tmpl: Likewise.
* gnu/system/examples/docker-image.tmpl: Likewise.
* gnu/system/examples/lightweight-desktop.tmpl: Likewise.
* gnu/system/install.scm (installation-os): Likewise.
* gnu/tests.scm (%simple-os): Likewise.
* gnu/tests/install.scm (%minimal-os, %minimal-os-on-vda):
(%separate-home-os, %encrypted-root-os, %btrfs-root-os): Likewise.
* tests/accounts.scm ("allocate-passwd")
("allocate-passwd with previous state"): Likewise.

1 files changed, 4 insertions, 10 deletions

diff --git a/gnu/tests/install.scm b/gnu/tests/install.scm
index 277908cc49..c0debbd840 100644
--- a/gnu/tests/install.scm
+++ b/gnu/tests/install.scm
@@ -74,8 +74,7 @@
                   (name "alice")
                   (comment "Bob's sister")
                   (group "users")
-                  (supplementary-groups '("wheel" "audio" "video"))
-                  (home-directory "/home/alice"))
+                  (supplementary-groups '("wheel" "audio" "video")))
                  %base-user-accounts))
     (services (cons (service marionette-service-type
                              (marionette-configuration
@@ -357,8 +356,7 @@ per %test-installed-os, this test is expensive in terms of CPU and storage.")
                   (name "alice")
                   (comment "Bob's sister")
                   (group "users")
-                  (supplementary-groups '("wheel" "audio" "video"))
-                  (home-directory "/home/alice"))
+                  (supplementary-groups '("wheel" "audio" "video")))
                  %base-user-accounts))
     (services (cons (service marionette-service-type
                              (marionette-configuration
@@ -435,12 +433,10 @@ reboot\n")
                          %base-file-systems))
     (users (cons* (user-account
                    (name "alice")
-                   (group "users")
-                   (home-directory "/home/alice"))
+                   (group "users"))
                   (user-account
                    (name "charlie")
-                   (group "users")
-                   (home-directory "/home/charlie"))
+                   (group "users"))
                   %base-user-accounts))
     (services (cons (service marionette-service-type
                              (marionette-configuration
@@ -655,7 +651,6 @@ by 'mdadm'.")
     (users (cons (user-account
                   (name "charlie")
                   (group "users")
-                  (home-directory "/home/charlie")
                   (supplementary-groups '("wheel" "audio" "video")))
                  %base-user-accounts))
     (services (cons (service marionette-service-type
@@ -776,7 +771,6 @@ build (current-guix) and then store a couple of full system images.")
     (users (cons (user-account
                   (name "charlie")
                   (group "users")
-                  (home-directory "/home/charlie")
                   (supplementary-groups '("wheel" "audio" "video")))
                  %base-user-accounts))
     (services (cons (service marionette-service-type