Access environment variables through Host object instead of directly.

third_party/WebKit/Tools/Scripts/webkitpy/common/system/systemhost.py

 # Copyright (c) 2011 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 12 matching lines @@
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import os
 import platform
 import sys
 
-from webkitpy.common.system import environment, executive, filesystem, platforminfo, user, workspace
+from webkitpy.common.system import executive, filesystem, platforminfo, user, workspace
 
 
 class SystemHost(object):
 
     def __init__(self):
         self.executable = sys.executable
         self.executive = executive.Executive()
         self.filesystem = filesystem.FileSystem()
         self.user = user.User()
         self.platform = platforminfo.PlatformInfo(sys, platform, self.filesystem, self.executive)
         self.workspace = workspace.Workspace(self.filesystem, self.executive)
         self.stdin = sys.stdin
         self.stdout = sys.stdout
         self.stderr = sys.stderr

[Dirk Pranke, 2016/07/14 19:28:13]

I would add a

  self.environ = os.environ

here instead.

[qyearsley, 2016/07/14 19:52:58]

Ah, excellent -- then the three methods below aren't necessary. This is what you
were thinking, right?

 
     def copy_current_environment(self):
-        return environment.Environment(os.environ.copy())
+        return os.environ.copy()
+
+    def get_env(self, key, default=None):
+        return os.environ.get(key, default)
+
+    def set_env(self, key, value):
+        os.environ[key] = value
 
     def print_(self, *args, **kwargs):
         sep = kwargs.get('sep', ' ')
         end = kwargs.get('end', '\n')
         stream = kwargs.get('stream', self.stdout)
         stream.write(sep.join([str(arg) for arg in args]) + end)
 
     def exit(self, returncode):
         sys.exit(returncode)