utils: Add insert-expression procedure.

* guix/utils.scm (define-module): Use (guix read-print) and export
(insert-expression).
(insert-expression): Add procedure.
* tests/utils.scm ("insert-expression"): Add test.

Change-Id: I971a43a78aa6ecaaef33c1a7a0db4b287eb85036
Signed-off-by: Ludovic Courtès <ludo@gnu.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/tests/utils.scm b/tests/utils.scm
index 5664165c85..cd54112846 100644
--- a/tests/utils.scm
+++ b/tests/utils.scm
@@ -5,6 +5,7 @@
 ;;; Copyright © 2021 Simon Tournier <zimon.toutoune@gmail.com>
 ;;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
 ;;; Copyright © 2023 Foundation Devices, Inc. <hello@foundationdevices.com>
+;;; Copyright © 2024 Herman Rimm <herman@rimm.ee>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -274,6 +275,19 @@ skip these tests."
                      string-reverse)
     (call-with-input-file temp-file get-string-all)))
 
+(test-equal "insert-expression"
+  "(define-public package-1\n  'package)\n
+(define-public package-2\n  'package)\n"
+  (begin
+    (call-with-output-file temp-file
+      (lambda (port)
+        (display "(define-public package-2\n  'package)\n" port)))
+    (insert-expression `((filename . ,temp-file)
+                         (line     . 0)
+                         (column   . 0))
+                       `(define-public package-1 'package))
+    (call-with-input-file temp-file get-string-all)))
+
 (test-equal "string-distance"
   '(0 1 1 5 5)
   (list