Adjust pnacl-translate sbtc flag override mechanism to append.

pnacl/driver/tests/driver_test_utils.py

 #!/usr/bin/python
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import driver_env
 import os
 from os.path import dirname
 import platform
 import sys
@@ skipping 12 matching lines @@
 
 def _SetupLinuxHostDir(env, nacl_dir):
   # Use the 32-bit path by default, but fall back to 64-bit if the 32-bit does
   # not exist.
   dir_template = os.path.join(nacl_dir, 'toolchain', 'pnacl_linux_x86',
                               'host_%s')
   dir_32 = dir_template % 'x86_32'
   dir_64 = dir_template % 'x86_64'
   env.set('BASE_HOST', dir_32 if os.path.exists(dir_32) else dir_64)
 
+def SetupNaClDir(env):
+  test_dir = os.path.abspath(dirname(__file__))
+  nacl_dir = dirname(dirname(dirname(test_dir)))
+  env.set('BASE_NACL', nacl_dir)
+
+def SetupToolchainDir(env):
+  test_dir = os.path.abspath(dirname(__file__))
+  nacl_dir = dirname(dirname(dirname(test_dir)))
+  toolchain_dir = os.path.join(nacl_dir, 'toolchain')
+  env.set('BASE_TOOLCHAIN', toolchain_dir)
+
 def SetupHostDir(env):
   # Some of the tools require 'BASE_HOST' to be set, because they end up
   # running one of the host binaries.
   test_dir = os.path.abspath(dirname(__file__))
   nacl_dir = dirname(dirname(dirname(test_dir)))
   if sys.platform == 'darwin':
     os_shortname = 'mac'
     host_arch = 'x86_64'
   elif sys.platform.startswith('linux'):
     _SetupLinuxHostDir(env, nacl_dir)
     return
   elif sys.platform in ('cygwin', 'win32'):
     os_shortname = 'win'
     host_arch= 'x86_32'
   host_dir = os.path.join(nacl_dir, 'toolchain',
                           'pnacl_%s_x86' % os_shortname,
                           'host_%s' % host_arch)
   env.set('BASE_HOST', host_dir)
 
-
 # A collection of override methods that mock driver_env.Environment.
 
 # One thing is we prevent having to read a driver.conf file,
 # so instead we have a base group of variables set for testing.
 def TestEnvReset(self):
   # Call to "super" class method (assumed to be driver_env.Environment).
   # TODO(jvoung): We may want a different way of overriding things.
   driver_env.Environment.reset(self)
   # The overrides.
   self.set('LIBMODE', 'newlib')
   self.set('PNACL_RUNNING_UNITTESTS', '1')
+  SetupNaClDir(self)
+  SetupToolchainDir(self)
   SetupHostDir(self)
 
-
 def ApplyTestEnvOverrides(env):
   """Register all the override methods and reset the env to a testable state.
   """
   driver_env.override_env('reset', TestEnvReset)
   env.reset()