[PATCH hglib] tests: handle the removal of `obsolete._enabled` in Mercurial

[Matt Harbison]

# HG changeset patch
# User Matt Harbison <matt_harbison at yahoo.com>
# Date 1557281819 14400
#      Tue May 07 22:16:59 2019 -0400
# Node ID 1febca34c800a64cc2c886d24920b936674cbd1c
# Parent  33b512aa8dba0cbe523188fbb62d30ae2125a236
tests: handle the removal of `obsolete._enabled` in Mercurial

I'm not sure why we can't just set `experimental.evolution=all`, but it didn't
work.

diff --git a/tests/test-hidden.py b/tests/test-hidden.py
--- a/tests/test-hidden.py
+++ b/tests/test-hidden.py
@@ -22,7 +22,7 @@
         super(test_obsolete_baselib, self).setUp()
         self.append('.hg/obs.py',
                     "import mercurial.obsolete\n"
-                    "mercurial.obsolete._enabled = True")
+                    "mercurial.obsolete.isenabled = lambda r, opt: True")
         self.append('.hg/hgrc','\n[extensions]\nobs=.hg/obs.py')
 
 class test_obsolete_client(test_obsolete_baselib):