Merge daira/2807.magic-folder-unicode-test-fail.1

refs ticket:2807

This allows tests to pass under an odd environment: our OS-X buildslave.
That process is started as a LaunchDaemon that doesn't provide any
Environment dictionary in the .plist file, so it runs with an empty
environment. On OS-X, this causes filesystem.encoding to default to
"utf-8", but locale.getpreferredencoding() returns "US-ASCII". The tests
previously assumed that any platform which used unicode for the
filesystem pathnames would also use it for sys.argv .

To simulate this without involving launchd, use "unset LANG", and
double-check that locale.getpreferredencoding() has changed.

This fix tolerates such platforms.

src/allmydata/test/cli/test_magic_folder.py

@@ -22,8 +22,8 @@ from allmydata import uri
 class MagicFolderCLITestMixin(CLITestMixin, GridTestMixin, NonASCIIPathMixin):
     def setUp(self):
         GridTestMixin.setUp(self)
-        self.alice_nickname = self.unicode_or_fallback(u"Alice\u00F8", u"Alice")
-        self.bob_nickname = self.unicode_or_fallback(u"Bob\u00F8", u"Bob")
+        self.alice_nickname = self.unicode_or_fallback(u"Alice\u00F8", u"Alice", io_as_well=True)
+        self.bob_nickname = self.unicode_or_fallback(u"Bob\u00F8", u"Bob", io_as_well=True)
 
     def do_create_magic_folder(self, client_num):
         d = self.do_cli("magic-folder", "create", "magic:", client_num=client_num)

src/allmydata/test/common_util.py

@@ -8,7 +8,8 @@ from twisted.trial import unittest
 
 from allmydata.util import fileutil, log
 from ..util.assertutil import precondition
-from allmydata.util.encodingutil import unicode_platform, get_filesystem_encoding
+from allmydata.util.encodingutil import (unicode_platform, get_filesystem_encoding,
+                                         get_io_encoding)
 from ..scripts import runner
 
 def skip_if_cannot_represent_filename(u):
@@ -95,14 +96,20 @@ class NonASCIIPathMixin:
             self.addCleanup(_cleanup)
         os.mkdir(dirpath)
 
-    def unicode_or_fallback(self, unicode_name, fallback_name):
-        if unicode_platform():
-            return unicode_name
-        try:
-            unicode_name.encode(get_filesystem_encoding())
-            return unicode_name
-        except UnicodeEncodeError:
-            return fallback_name
+    def unicode_or_fallback(self, unicode_name, fallback_name, io_as_well=False):
+        if not unicode_platform():
+            try:
+                unicode_name.encode(get_filesystem_encoding())
+            except UnicodeEncodeError:
+                return fallback_name
+
+        if io_as_well:
+            try:
+                unicode_name.encode(get_io_encoding())
+            except UnicodeEncodeError:
+                return fallback_name
+
+        return unicode_name
 
 
 class SignalMixin: