giving the linkmap issue its own patch page to make it more readable

doc/bugs/linkmap_displays_underscore_escapes/the_patch.pl

@@ -0,0 +1,68 @@
+From efbb1121ffdc146f5c9a481a51f23ad151b9f240 Mon Sep 17 00:00:00 2001
+From: chrysn <chrysn@fsfe.org>
+Date: Thu, 15 Mar 2012 14:38:42 +0100
+Subject: [PATCH] display the pagetitle() in linkmaps
+
+without this patch, linkmaps display underscores and underscore escape
+sequences in the rendered output.
+
+this introduces a pageescape function, which invoces pagetitle() to get
+rid of underscore escapes and wraps the resulting utf8 string
+appropriately for inclusion in a dot file (using dot's html encoding
+because it can represent the '\"' dyad properly, and because it doesn't
+need special-casing of newlines).
+---
+ IkiWiki/Plugin/linkmap.pm |   17 +++++++++++++++--
+ 1 files changed, 15 insertions(+), 2 deletions(-)
+
+diff --git a/IkiWiki/Plugin/linkmap.pm b/IkiWiki/Plugin/linkmap.pm
+index ac26e07..b5ef1a1 100644
+--- a/IkiWiki/Plugin/linkmap.pm
++++ b/IkiWiki/Plugin/linkmap.pm
+@@ -5,6 +5,7 @@ use warnings;
+ use strict;
+ use IkiWiki 3.00;
+ use IPC::Open2;
++use HTML::Entities;
+ 
+ sub import {
+        hook(type => "getsetup", id => "linkmap", call => \&getsetup);
+@@ -22,6 +23,18 @@ sub getsetup () {
+ 
+ my $mapnum=0;
+ 
++sub pageescape {
++       my $item = shift;
++       # encoding explicitly in case ikiwiki is configured to accept <> or &
++       # in file names
++       my $title = pagetitle($item, 1);
++       # it would not be necessary to encode *all* the html entities (<> would
++       # be sufficient, &" probably a good idea), as dot accepts utf8, but it
++       # isn't bad either
++       $title = encode_entities($title);
++       return("<$title>");
++}
++
+ sub preprocess (@) {
+        my %params=@_;
+ 
+@@ -63,7 +76,7 @@ sub preprocess (@) {
+        my $show=sub {
+                my $item=shift;
+                if (! $shown{$item}) {
+-                       print OUT "\"$item\" [shape=box,href=\"$mapitems{$item}\"];\n";
++                       print OUT pageescape($item)." [shape=box,href=\"$mapitems{$item}\"];\n";
+                        $shown{$item}=1;
+                }
+        };
+@@ -74,7 +87,7 @@ sub preprocess (@) {
+                        foreach my $endpoint ($item, $link) {
+                                $show->($endpoint);
+                        }
+-                       print OUT "\"$item\" -> \"$link\";\n";
++                       print OUT pageescape($item)." -> ".pageescape($link).";\n";
+                }
+        }
+        print OUT "}\n";
+-- 
+1.7.9.1