Add transient plugin, which adds ~/.ikiwiki/transient as an underlay

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diff --git a/IkiWiki/Plugin/transient.pm b/IkiWiki/Plugin/transient.pm
new file mode 100644 (file)
index 0000000..5764467
--- /dev/null
+++ b/IkiWiki/Plugin/transient.pm
@@ -0,0 +1,33 @@
+#!/usr/bin/perl
+package IkiWiki::Plugin::transient;
+
+use warnings;
+use strict;
+use IkiWiki 3.00;
+
+sub import {
+       hook(type => "getsetup", id => "transient",  call => \&getsetup);
+       hook(type => "checkconfig", id => "transient", call => \&checkconfig);
+}
+
+sub getsetup () {
+       return
+               plugin => {
+                       # this plugin is safe but only makes sense as a
+                       # dependency; similarly, it needs a rebuild but
+                       # only if something else does
+                       safe => 0,
+                       rebuild => 0,
+               },
+}
+
+our $transientdir;
+
+sub checkconfig () {
+       eval q{use Cwd 'abs_path'};
+       error($@) if $@;
+       $transientdir = abs_path($config{wikistatedir})."/transient";
+       add_underlay($transientdir);
+}
+
+1;