[PATCH 1 of 4] tests: tests for revlog version and flags loading

[Gregory Szorc]

# HG changeset patch
# User Gregory Szorc <gregory.szorc at gmail.com>
# Date 1495249295 25200
#      Fri May 19 20:01:35 2017 -0700
# Node ID 40748da9c7c56836f815582cf9a367097755859d
# Parent  a438f5a3bc092f54e14f45e2115a36312c2ed302
tests: tests for revlog version and flags loading

We didn't have explicit test coverage of these branches.
Better late than never.

diff --git a/tests/test-revlog.t b/tests/test-revlog.t
--- a/tests/test-revlog.t
+++ b/tests/test-revlog.t
@@ -1,3 +1,35 @@
+  $ hg init empty-repo
+  $ cd empty-repo
+
+Flags on revlog version 0 are rejected
+
+  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
+  ...     fh.write('\x00\x01\x00\x00')
+
+  $ hg log
+  abort: index 00changelog.i unknown flags 0x01 for format v0!
+  [255]
+
+Unknown flags on revlog version 1 are rejected
+
+  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
+  ...     fh.write('\x00\x04\x00\x01')
+
+  $ hg log
+  abort: index 00changelog.i unknown flags 0x04 for revlogng!
+  [255]
+
+Unknown version is rejected
+
+  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
+  ...     fh.write('\x00\x00\x00\x02')
+
+  $ hg log
+  abort: index 00changelog.i unknown format 2!
+  [255]
+
+  $ cd ..
+
 Test for CVE-2016-3630
 
   $ hg init