Bug#986875: chezscheme: leaves alternatives after upgrade from buster: /usr/bin/scheme -> /etc/alternatives/scheme -> /usr/bin/chezscheme9.5

[Andreas Beckmann]

Followup-For: Bug #986875
Control: tag -1 patch

The attached patch cleans the obsolete alternatives on all the upgrade
paths where I had previously observed them.

Andreas

diff -Nru chezscheme-9.5.4+dfsg/debian/changelog 
chezscheme-9.5.4+dfsg/debian/changelog
--- chezscheme-9.5.4+dfsg/debian/changelog      2020-09-17 21:27:16.000000000 
+0200
+++ chezscheme-9.5.4+dfsg/debian/changelog      2021-04-13 11:34:58.000000000 
+0200
@@ -1,3 +1,10 @@
+chezscheme (9.5.4+dfsg-4) UNRELEASED; urgency=medium
+
+  * chezscheme.postinst: Clean up obsolete versioned alternatives on upgrades
+    from buster.  (Closes: #986875)
+
+ -- Andreas Beckmann <a...@debian.org>  Tue, 13 Apr 2021 11:34:58 +0200
+
 chezscheme (9.5.4+dfsg-3) unstable; urgency=medium
 
   * debian/rules: Only override dh_link if chezscheme is built.
diff -Nru chezscheme-9.5.4+dfsg/debian/chezscheme.postinst 
chezscheme-9.5.4+dfsg/debian/chezscheme.postinst
--- chezscheme-9.5.4+dfsg/debian/chezscheme.postinst    2020-09-07 
19:08:14.000000000 +0200
+++ chezscheme-9.5.4+dfsg/debian/chezscheme.postinst    2021-04-13 
11:34:12.000000000 +0200
@@ -17,6 +17,13 @@
                         --slave /usr/share/man/man1/scheme-script.1.gz \
                                 scheme-script.1.gz \
                                 /usr/share/man/man1/scheme-script-chez.1.gz
+
+    if dpkg --compare-versions "$2" lt-nl "9.5.4+dfsg-4~" ; then
+        CHEZ_VERSION=9.5
+        update-alternatives --remove scheme /usr/bin/chezscheme${CHEZ_VERSION}
+        update-alternatives --remove scheme-script 
/usr/bin/chezscheme${CHEZ_VERSION}
+    fi
+
 fi
 
 #DEBHELPER#