# HG changeset patch
# User Anton Shestakov <av6@dwimlabs.net>
# Date 1617104152 -28800
# Node ID d7ed8881045711f9e3a76162c57fb32dad2612a0
# Parent  97f5b5b25299602ba6171eee02ef9578fdd4a607
evolve: make firstmergecache.save/load use struct.unpack/pack (issue6354)

arraytobytes() and arrayfrombytes() is not cross-platform.

diff -r 97f5b5b25299 -r d7ed88810457 hgext3rd/evolve/firstmergecache.py
--- a/hgext3rd/evolve/firstmergecache.py	Wed Mar 31 20:13:31 2021 +0800
+++ b/hgext3rd/evolve/firstmergecache.py	Tue Mar 30 19:35:52 2021 +0800
@@ -129,20 +129,23 @@
         assert repo.filtername is None
 
         data = repo.cachevfs.tryread(self._filepath)
+        self._cachekey = self.emptykey
         self._data = array.array(r'l')
-        if not data:
-            self._cachekey = self.emptykey
-        else:
+        if data:
             headerdata = data[:self._cachekeysize]
-            self._cachekey = self._deserializecachekey(headerdata)
-            compat.arrayfrombytes(self._data, data[self._cachekeysize:])
+            cachekey = self._deserializecachekey(headerdata)
+            expected = self._datastruct.size * (cachekey[0] + 1)
+            data = data[self._cachekeysize:]
+            if len(data) == expected:
+                self._data.extend(self._deserializedata(data))
+                self._cachekey = cachekey
+            else:
+                repo.ui.debug(b'firstmergecache file seems to be corrupted, '
+                              b'it will be rebuilt from scratch\n')
         self._ondiskkey = self._cachekey
 
     def save(self, repo):
         """save the data to disk
-
-        Format is pretty simple, we serialise the cache key and then drop the
-        bytearray.
         """
         if self._cachekey is None or self._cachekey == self._ondiskkey:
             return
@@ -151,7 +154,7 @@
             cachefile = repo.cachevfs(self._filepath, b'w', atomictemp=True)
             headerdata = self._serializecachekey()
             cachefile.write(headerdata)
-            cachefile.write(compat.arraytobytes(self._data))
+            cachefile.write(self._serializedata(self._data))
             cachefile.close()
             self._ondiskkey = self._cachekey
         except (IOError, OSError) as exc:
diff -r 97f5b5b25299 -r d7ed88810457 tests/test-discovery-obshashrange-cache.t
--- a/tests/test-discovery-obshashrange-cache.t	Wed Mar 31 20:13:31 2021 +0800
+++ b/tests/test-discovery-obshashrange-cache.t	Tue Mar 30 19:35:52 2021 +0800
@@ -292,6 +292,46 @@
   f69452c5b1af -1
   4de32a90b66c -1
 
+  $ "$PYTHON" repack.py main/.hg/cache/evoext-firstmerge-00
+  $ f -H main/.hg/cache/evoext-firstmerge-00
+  main/.hg/cache/evoext-firstmerge-00:
+  0000: 00 00 00 07 4d e3 2a 90 b6 6c d0 83 eb f3 c0 0b |....M.*..l......|
+  0010: 41 27 7a a7 ab ca 51 dd ff ff ff ff ff ff ff ff |A'z...Q.........|
+  0020: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|
+  0030: ff ff ff ff ff ff ff ff                         |........|
+
+  $ hg -R main debugfirstmergecache --debug
+  firstmergecache file seems to be corrupted, it will be rebuilt from scratch
+  1ea73414a91b -1
+  66f7d451a68b -1
+  01241442b3c2 -1
+  2dc09a01254d -1
+  bebd167eb94d -1
+  c8d03c1b5e94 -1
+  f69452c5b1af -1
+  4de32a90b66c -1
+
+  $ "$PYTHON" truncate.py main/.hg/cache/evoext-firstmerge-00 -4
+  $ f -H main/.hg/cache/evoext-firstmerge-00
+  main/.hg/cache/evoext-firstmerge-00:
+  0000: 00 00 00 07 4d e3 2a 90 b6 6c d0 83 eb f3 c0 0b |....M.*..l......|
+  0010: 41 27 7a a7 ab ca 51 dd ff ff ff ff ff ff ff ff |A'z...Q.........|
+  0020: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|
+  0030: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|
+  0040: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|
+  0050: ff ff ff ff                                     |....|
+
+  $ hg -R main debugfirstmergecache --debug
+  firstmergecache file seems to be corrupted, it will be rebuilt from scratch
+  1ea73414a91b -1
+  66f7d451a68b -1
+  01241442b3c2 -1
+  2dc09a01254d -1
+  bebd167eb94d -1
+  c8d03c1b5e94 -1
+  f69452c5b1af -1
+  4de32a90b66c -1
+
   $ hg -R main debugstablesortcache --debug
   number of revisions:            8
   number of merge:                0