From ffa73790b5c381df6e0385995b720dd24188969b Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@gnu.kitenet.net>
Date: Sat, 3 Oct 2009 14:14:30 -0400
Subject: [PATCH] Fix a bug that could lead to duplicate links being recorded
 for tags.

Here I was bitten by perl's aliasing of foreach variables
to the loop array contents, and match_link accidentially changed
the contents of %links.

In Jon's testcase, a tag added an absolute link, which was
made relative by the above bug, and then the link was added
again in preprocess, and turned into a duplicate.
---
 IkiWiki.pm                                            | 6 +++---
 debian/changelog                                      | 2 ++
 doc/bugs/brokenlinks_accumulates_duplicate_items.mdwn | 3 +++
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/IkiWiki.pm b/IkiWiki.pm
index 974e36902..2637f6017 100644
--- a/IkiWiki.pm
+++ b/IkiWiki.pm
@@ -2052,10 +2052,10 @@ sub match_link ($$;@) {
 		else {
 			return IkiWiki::SuccessReason->new("$page links to page $p matching $link")
 				if match_glob($p, $link, %params);
-			$p=~s/^\///;
+			my ($p_rel)=$p=~/^\/?(.*)/;
 			$link=~s/^\///;
-			return IkiWiki::SuccessReason->new("$page links to page $p matching $link")
-				if match_glob($p, $link, %params);
+			return IkiWiki::SuccessReason->new("$page links to page $p_rel matching $link")
+				if match_glob($p_rel, $link, %params);
 		}
 	}
 	return IkiWiki::FailReason->new("$page does not link to $link");
diff --git a/debian/changelog b/debian/changelog
index b6383bacb..ca5409af7 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -8,6 +8,8 @@ ikiwiki (3.14159266) UNRELEASED; urgency=low
     to the body tag.
   * Support RPC::XML 0.69's incompatable object instantiation method.
   * mirrorlist: Display nothing if list is empty.
+  * Fix a bug that could lead to duplicate links being recorded
+    for tags.
 
  -- Joey Hess <joeyh@debian.org>  Sun, 27 Sep 2009 17:40:03 -0400
 
diff --git a/doc/bugs/brokenlinks_accumulates_duplicate_items.mdwn b/doc/bugs/brokenlinks_accumulates_duplicate_items.mdwn
index 2091570d1..d07b2381d 100644
--- a/doc/bugs/brokenlinks_accumulates_duplicate_items.mdwn
+++ b/doc/bugs/brokenlinks_accumulates_duplicate_items.mdwn
@@ -20,3 +20,6 @@ ikiwiki version 3.14159265.
 > source and the `.ikiwiki` directory to reproduce this. --[[Joey]] 
 
 >> Hi Joey, thanks for your response. I've reproduced it post rebuild and after having ran ikiwiki-transition and many refreshes (both resulting from content changes and otherwise) unfortunately, with ikiwiki 3.14159265 (different machine to above report, though). I will contact you privately to provide a git URL and a copy of my .ikiwiki. -- [[Jon]]
+
+>>> Found the bug that was causing duplicates to get in, and fixed it.
+>>> [[done]] --[[Joey]]