Disable the Preferences link if no plugin with an auth hook is enabled.

IkiWiki/Plugin/passwordauth.pm

@@ -8,9 +8,10 @@ use IkiWiki 3.00;
 
 sub import {
 	hook(type => "getsetup", id => "passwordauth", "call" => \&getsetup);
-        hook(type => "formbuilder_setup", id => "passwordauth", call => \&formbuilder_setup);
-        hook(type => "formbuilder", id => "passwordauth", call => \&formbuilder);
+	hook(type => "formbuilder_setup", id => "passwordauth", call => \&formbuilder_setup);
+	hook(type => "formbuilder", id => "passwordauth", call => \&formbuilder);
 	hook(type => "sessioncgi", id => "passwordauth", call => \&sessioncgi);
+	hook(type => "auth", id => "passwordauth", call => \&auth);
 }
 
 sub getsetup () {
@@ -337,4 +338,10 @@ sub sessioncgi ($$) {
 	}
 }
 
+sub auth ($$) {
+	# While this hook is not currently used, it needs to exist
+	# so ikiwiki knows that the wiki supports logins, and will
+	# enable the Preferences page.
+}
+
 1

IkiWiki/Render.pm

@@ -65,7 +65,8 @@ sub genpage ($$) {
 	if (length $config{cgiurl}) {
 		$template->param(editurl => cgiurl(do => "edit", page => $page))
 			if IkiWiki->can("cgi_editpage");
-		$template->param(prefsurl => cgiurl(do => "prefs"));
+		$template->param(prefsurl => cgiurl(do => "prefs"))
+			if exists $hooks{auth};
 		$actions++;
 	}
 		

debian/changelog

@@ -22,6 +22,7 @@ ikiwiki (3.141) UNRELEASED; urgency=low
     is not available. Closes: #532285
   * meta: Add openid delegate parameter to allow delegating only
     openid or openid2.
+  * Disable the Preferences link if no plugin with an auth hook is enabled.
 
  -- Joey Hess <joeyh@debian.org>  Tue, 02 Jun 2009 17:03:41 -0400
 

doc/todo/Allow_disabling_edit_and_preferences_links.mdwn

@@ -67,3 +67,13 @@ Patch:
 >>> Adding a new `canlogin` hook looks like overkill to me.  [[Joey]], how
 >>> about making registration of the `auth` hook mandatory for all plugins
 >>> making sense of the "Preferences" link? --[[Lunar]]
+
+>>>> Hmm, using the `auth` hook existance does seem like a nice solution.
+>>>> While splitting the preferences code out into its own plugin is
+>>>> easily enough done, it has the minor problem of being yet another
+>>>> file nearly all ikiwikis will have to load, and also, prefs would
+>>>> have to be disabled manually. So I like that using the hook would
+>>>> cause it to auto-disable if nothing uses it. It's a bit ugly that
+>>>> passwordauth doesn't need an auth hook (it could be reorged to
+>>>> use it instead of formbuilder, maybe) and would probably just have an
+>>>> empty one. Thanks for the idea. --[[Joey]]  [[done]]