bug#35542: Installer does not display full backtrace on error

[Mathieu Othacehe]

Hello,

> I believe I read about Guile error messages not doing line wrapping in
> terminals on the Guix or Guile mailing lists recently, but I cannot
> find it.  Proper line wrapping may be the better solution.

In fact the textbox where the backtrace is displayed isn't doing any
line wrapping. The attached patch fixes the issue.

Thanks,

Mathieu

>From f68ded2f134d55c20f98300c0514c4fc18cd1d50 Mon Sep 17 00:00:00 2001
From: Mathieu Othacehe <address@hidden>
Date: Sat, 4 May 2019 11:33:33 +0200
Subject: [PATCH] installer: Reflow run-file-textbox-page text.

* gnu/installer/newt/page.scm (run-file-textbox-page): Reflow FILE-TEXT so
that it fits horizontally in the textbox.
---
 gnu/installer/newt/page.scm | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gnu/installer/newt/page.scm b/gnu/installer/newt/page.scm
index 3173d54737..8a32c403df 100644
--- a/gnu/installer/newt/page.scm
+++ b/gnu/installer/newt/page.scm
@@ -559,7 +559,12 @@ ITEMS when 'Ok' is pressed."
                          '())))))
          (form (make-form)))
 
-    (set-textbox-text file-textbox file-text)
+    (set-textbox-text file-textbox
+                      (receive (_w _h text)
+                          (reflow-text file-text
+                                       file-textbox-width
+                                       0 0)
+                        text))
     (add-form-to-grid grid form #t)
     (make-wrapped-grid-window grid title)
 
-- 
2.17.1