Make uses of metaclasses portable across Python versions

[zturner]

Summary

This uses the six.add_metaclass() decorator for portable metaclass specification.

[tfiala]

Looks good.

[zturner]

Thanks. This is still blocked on my 2 earlier CLs (one adding six to the repo, and the other hooking up six to be recognized by dotest). If you get a chance can you take a look at those?

[tfiala]

In D13912#271481, @zturner wrote:

Thanks. This is still blocked on my 2 earlier CLs (one adding six to the repo, and the other hooking up six to be recognized by dotest). If you get a chance can you take a look at those?

Yep, I didn't read them in time order :-) All 3 looked good.

[zturner]

Thanks!

[tfiala]

Sure thing!

test/dotest.py

 
 import six
 
-
 def is_exe(fpath):
     """Returns true if fpath is an executable."""
     return os.path.isfile(fpath) and os.access(fpath, os.X_OK)

test/lldbtest.py

 
 from __future__ import print_function
 
+import lldb_shared
+
 import abc
 import gc
 import glob

 import lldb
 import lldbtest_config
 import lldbutil
-from _pyio import __metaclass__
+
+from six import add_metaclass
 
 if sys.version_info.major < 3:
     import urlparse

             print(self.getvalue(), file=self.session)
         self.close()
 
+@add_metaclass(abc.ABCMeta)
 class _BaseProcess(object):
-    __metaclass__ = abc.ABCMeta
 
     @abc.abstractproperty
     def pid(self):

                 newattrs[attrname] = attrvalue
         return super(LLDBTestCaseFactory, cls).__new__(cls, name, bases, newattrs)
 
+# Setup the metaclass for this class to change the list of the test methods when a new class is loaded
+@add_metaclass(LLDBTestCaseFactory)
 class TestBase(Base):
     """
     This abstract base class is meant to be subclassed.  It provides default

     # Can be overridden by the LLDB_TIME_WAIT_NEXT_LAUNCH environment variable.
     timeWaitNextLaunch = 1.0;
 
-    # Setup the metaclass for this class to change the list of the test methods when a new class is loaded
-    __metaclass__ = LLDBTestCaseFactory
-
     def doDelay(self):
         """See option -w of dotest.py."""
         if ("LLDB_WAIT_BETWEEN_TEST_CASES" in os.environ and