package: Honor '--dry-run' when target profile is already in store.

Fixes <https://issues.guix.gnu.org/53267>.
Reported by Tirifto <tirifto@posteo.cz>.

Regression introduced in 65ffb9388c1c3d870cb07e4cb3ef12c9ac06a161.

In the (unlikely) case where the profile we're targeting with "guix
upgrade -n" or similar is already built, a new profile generation would
be created and linked to despite the use of '-n'.  This is because
65ffb9388c1c3d870cb07e4cb3ef12c9ac06a161 assumed that dry-run behavior
would be handled solely by the build handler, which is not the case when
there's nothing to build.

* guix/scripts/package.scm (build-and-use-profile): Reintroduce #:dry-run?
and honor it.
(process-actions): Pass #:dry-run? to 'build-and-use-profile'.
* tests/guix-package-net.sh: Add test.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/guix-package-net.sh b/tests/guix-package-net.sh
index a3beb238fe8..1cdeff773a3 100644
--- a/tests/guix-package-net.sh
+++ b/tests/guix-package-net.sh
@@ -196,6 +196,16 @@ EOF
 guix package --bootstrap -p "$profile" -i gcc-bootstrap
 installed="`guix package -p "$profile" -I | cut -f1`"
 
+# Dry-run upgrade.  Make sure no new generation is created when things are
+# already in store and '-n' is used: <https://issues.guix.gnu.org/53267>.
+V_MINOR=0
+export V_MINOR
+profile_before="$(readlink "$profile")"
+guix package -p "$profile" --bootstrap -L "$module_dir" -u # build the profile
+guix package -p "$profile" --roll-back
+guix package -p "$profile" --bootstrap -L "$module_dir" -u . -n # check '-n'
+test "$(readlink "$profile")" = "$profile_before"
+
 for i in 1 2
 do
     V_MINOR="$i"