RewriteRule redirecting to index.php - php

Question

This is something weird.
In a website that I'm working on, which uses Zend framework, there was a requirement to redirect any URLs ending with "/" (e.g., http://test.com/test-url/) to the same URL without the "/" (e.g., http://test.com/test-url).
I added this to the .htaccess file:
RewriteRule ^(.+[^/])/$ /$1 [R=301,L]
For many URLs this is working fine. But for URLs like http://test.com/index/test-url/ this gets redirected to http://test.com/index.php/test-url, which is undesired. Can somebody throw some light on why this happens please?
I know you can complain about the unfriendly URLs like "/index/test", but I need to live with it for now :)
The requirement was to avoid these being seen as duplicate URLs by search bots, which affects SEO as some believe.
Here is the complete .htaccess file:
RewriteEngine On
RewriteBase /
RewriteRule ^(.+[^/])/$ /$1 [R=301,L]
# Some other strange redirections
RewriteRule ^index/$ / [R=301]
RewriteRule ^css/$ / [R=301]
RewriteRule ^js/$ / [R=301]
RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ index.php [NC,L]
# compression
<IfModule mod_deflate.c>
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE image/svg+xml
AddOutputFilterByType DEFLATE application/rss+xml
AddOutputFilterByType DEFLATE application/atom_xml
AddOutputFilterByType DEFLATE text/javascript
AddOutputFilterByType DEFLATE application/javascript
AddOutputFilterByType DEFLATE application/x-javascript
AddOutputFilterByType DEFLATE application/x-httpd-php
AddOutputFilterByType DEFLATE application/x-httpd-fastphp
AddOutputFilterByType DEFLATE application/x-httpd-eruby
</IfModule>

Answer 1

This behaviour seems to surface when you have the MultiViews option turned on. Multiviews allows for content negotiation with mod_negotiation. You can turn it off by adding the following in the very top of your .htaccess:
Options -MultiViews
For more information, see the documentation and some more information about content negotiation.
Alternatively you can rename index.php to prettybutterflies.php and change your RewriteRule to:
RewriteRule ^ prettybutterflies.php [NC,L]