From 57e56828f5b03f8fb31631f36731f989d4335607 Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@kitenet.net>
Date: Fri, 18 Jun 2010 16:40:47 -0400
Subject: [PATCH] store state to avoid needing to rebuild when changing theme

---
 IkiWiki/Plugin/theme.pm               | 30 ++++++++++++++++++++++++++-
 doc/bugs/underlaydir_file_expose.mdwn |  1 +
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/IkiWiki/Plugin/theme.pm b/IkiWiki/Plugin/theme.pm
index ba6966381..03b0816ed 100644
--- a/IkiWiki/Plugin/theme.pm
+++ b/IkiWiki/Plugin/theme.pm
@@ -8,6 +8,7 @@ use IkiWiki 3.00;
 sub import {
 	hook(type => "getsetup", id => "theme", call => \&getsetup);
 	hook(type => "checkconfig", id => "theme", call => \&checkconfig);
+	hook(type => "needsbuild", id => "theme", call => \&needsbuild);
 }
 
 sub getsetup () {
@@ -22,7 +23,7 @@ sub getsetup () {
 			example => "actiontabs",
 			description => "name of theme to enable",
 			safe => 1,
-			rebuild => 1,
+			rebuild => 0,
 		},
 }
 
@@ -34,4 +35,31 @@ sub checkconfig () {
 	}
 }
 
+sub needsbuild ($) {
+	my $needsbuild=shift;
+	if (($config{theme} || '') ne ($wikistate{theme}{currenttheme} || '')) {
+		# theme changed; ensure all files in the theme are built
+		my %needsbuild=map { $_ => 1 } @$needsbuild;
+		if ($config{theme}) {
+			foreach my $file (glob("$config{underlaydirbase}/themes/$config{theme}/*")) {
+				if (-f $file) {
+					my $f=IkiWiki::basename($file);
+					push @$needsbuild, $f
+						unless $needsbuild{$f};
+				}
+			}
+		}
+		elsif ($wikistate{theme}{currenttheme}) {
+			foreach my $file (glob("$config{underlaydirbase}/themes/$wikistate{theme}{currenttheme}/*")) {
+				my $f=IkiWiki::basename($file);
+				if (-f $file && defined eval { srcfile($f) }) {
+					push @$needsbuild, $f;
+				}
+			}
+		}
+		
+		$wikistate{theme}{currenttheme}=$config{theme};
+	}
+}
+
 1
diff --git a/doc/bugs/underlaydir_file_expose.mdwn b/doc/bugs/underlaydir_file_expose.mdwn
index ca492e396..4ee30e39d 100644
--- a/doc/bugs/underlaydir_file_expose.mdwn
+++ b/doc/bugs/underlaydir_file_expose.mdwn
@@ -9,4 +9,5 @@ gets rebuilt.)
 > A related problem occurs if changing a site's theme with the
 > [[plugins/theme]] plugin. The style.css of the old and new theme
 > often has the same mtime, so ikiwiki does not update it w/o a rebuild.
+> This is worked around in theme.pm with a special-purpose needsbuild hook.
 > --[[Joey]]
-- 
2.26.2