# HG changeset patch
# User Ludovic Chabant <ludovic@chabant.com>
# Date 1428075861 25200
# Node ID 91b07f9efdc1ef7e1841e027a162fdbedfb82aec
# Parent  d8c28e496bb30466ecdbb4dfc7c584a818ef367f
bake: Use a rotating bake record.

diff -r d8c28e496bb3 -r 91b07f9efdc1 piecrust/baking/baker.py
--- a/piecrust/baking/baker.py	Wed Apr 01 00:35:04 2015 -0700
+++ b/piecrust/baking/baker.py	Fri Apr 03 08:44:21 2015 -0700
@@ -52,9 +52,8 @@
         # Load/create the bake record.
         record = TransitionalBakeRecord()
         record_cache = self.app.cache.getCache('baker')
-        record_name = (
-                hashlib.md5(self.out_dir.encode('utf8')).hexdigest() +
-                '.record')
+        record_id = hashlib.md5(self.out_dir.encode('utf8')).hexdigest()
+        record_name = record_id + '.record'
         if not self.force and record_cache.has(record_name):
             t = time.clock()
             record.loadPrevious(record_cache.getCachePath(record_name))
@@ -88,6 +87,18 @@
         # Delete files from the output.
         self._handleDeletetions(record)
 
+        # Backup previous records.
+        for i in range(8, -1, -1):
+            suffix = '' if i == 0 else '.%d' % i
+            record_path = record_cache.getCachePath(
+                    '%s%s.record' % (record_id, suffix))
+            if os.path.exists(record_path):
+                record_path_next = record_cache.getCachePath(
+                        '%s.%s.record' % (record_id, i + 1))
+                if os.path.exists(record_path_next):
+                    os.remove(record_path_next)
+                os.rename(record_path, record_path_next)
+
         # Save the bake record.
         t = time.clock()
         record.current.bake_time = time.time()