read-print: Support printing multi-line comments.

* guix/read-print.scm (%not-newline): New variable.
(print-multi-line-comment): New procedure.
(pretty-print-with-comments): Use it.
* tests/read-print.scm ("pretty-print-with-comments, multi-line
comment"): New test.

1 files changed, 14 insertions, 0 deletions

diff --git a/tests/read-print.scm b/tests/read-print.scm
index e3f23194af3..004fcff19f1 100644
--- a/tests/read-print.scm
+++ b/tests/read-print.scm
@@ -341,4 +341,18 @@ mnopqrstuvwxyz.\")"
                                     #:format-vertical-space
                                     canonicalize-vertical-space)))))
 
+(test-equal "pretty-print-with-comments, multi-line comment"
+  "\
+(list abc
+      ;; This comment spans
+      ;; two lines.
+      def)"
+  (call-with-output-string
+    (lambda (port)
+      (pretty-print-with-comments port
+                                  `(list abc ,(comment "\
+;; This comment spans\n
+;; two lines.\n")
+                                         def)))))
+
 (test-end)