* ``DetailStream`` was ambiguous about whether it handled bytes or characters,

  which matters a lot for Python3. It now is deprecated with ByteStream and
  StringStream replacing it. (Robert Collins)

* Fixtures is now Python3 compatible. (Robert Collins)

10 files changed, 158 insertions, 61 deletions

diff --git a/NEWS b/NEWS
index 4f82b24..a888fe1 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,12 @@ NEXT
 CHANGES
 -------
 
+* ``DetailStream`` was ambiguous about whether it handled bytes or characters,
+  which matters a lot for Python3. It now is deprecated with ByteStream and
+  StringStream replacing it. (Robert Collins)
+
+* Fixtures is now Python3 compatible. (Robert Collins)
+
 * ``FakeLogger`` has been split out into a ``LogHandler`` fixture that can
   inject arbitrary handlers, giving more flexability. (Jonathan Lange)
 
diff --git a/lib/fixtures/__init__.py b/lib/fixtures/__init__.py
index 1390ac8..1c03bf8 100644
--- a/lib/fixtures/__init__.py
+++ b/lib/fixtures/__init__.py
@@ -39,6 +39,7 @@ Most users will want to look at TestWithFixtures and Fixture, to start with.
 __version__ = (0, 3, 10, 'final', 0)
 
 __all__ = [
+    'ByteStream',
     'DetailStream',
     'EnvironmentVariable',
     'EnvironmentVariableFixture',
@@ -55,6 +56,7 @@ __all__ = [
     'PopenFixture',
     'PythonPackage',
     'PythonPathEntry',
+    'StringStream',
     'TempDir',
     'TempHomeDir',
     'TestWithFixtures',
@@ -69,6 +71,7 @@ from fixtures.fixture import (
     MethodFixture,
     )
 from fixtures._fixtures import (
+    ByteStream,
     DetailStream,
     EnvironmentVariable,
     EnvironmentVariableFixture,
@@ -82,6 +85,7 @@ from fixtures._fixtures import (
     PopenFixture,
     PythonPackage,
     PythonPathEntry,
+    StringStream,
     TempDir,
     TempHomeDir,
     Timeout,
diff --git a/lib/fixtures/_fixtures/__init__.py b/lib/fixtures/_fixtures/__init__.py
index e113e1e..1d54858 100644
--- a/lib/fixtures/_fixtures/__init__.py
+++ b/lib/fixtures/_fixtures/__init__.py
@@ -17,6 +17,7 @@
 """Included fixtures."""
 
 __all__ = [
+    'ByteStream',
     'DetailStream',
     'EnvironmentVariable',
     'EnvironmentVariableFixture',
@@ -30,6 +31,7 @@ __all__ = [
     'PopenFixture',
     'PythonPackage',
     'PythonPathEntry',
+    'StringStream',
     'TempDir',
     'TempHomeDir',
     'Timeout',
@@ -37,7 +39,6 @@ __all__ = [
     ]
 
 
-from fixtures._fixtures.detailstream import DetailStream
 from fixtures._fixtures.environ import (
     EnvironmentVariable,
     EnvironmentVariableFixture,
@@ -55,6 +56,11 @@ from fixtures._fixtures.popen import (
 from fixtures._fixtures.packagepath import PackagePathEntry
 from fixtures._fixtures.pythonpackage import PythonPackage
 from fixtures._fixtures.pythonpath import PythonPathEntry
+from fixtures._fixtures.streams import (
+    ByteStream,
+    DetailStream,
+    StringStream,
+    )
 from fixtures._fixtures.tempdir import (
     NestedTempfile,
     TempDir,
diff --git a/lib/fixtures/_fixtures/detailstream.py b/lib/fixtures/_fixtures/detailstream.py
deleted file mode 100644
index 779ef18..0000000
--- a/lib/fixtures/_fixtures/detailstream.py
+++ /dev/null
@@ -1,43 +0,0 @@
-#  fixtures: Fixtures with cleanups for testing and convenience.
-#
-# Copyright (c) 2012, Robert Collins <robertc@robertcollins.net>
-#
-# Licensed under either the Apache License, Version 2.0 or the BSD 3-clause
-# license at the users choice. A copy of both licenses are available in the
-# project source as Apache-2.0 and BSD. You may not use this file except in
-# compliance with one of these two licences.
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under these licenses is distributed on an "AS IS" BASIS, WITHOUT
-# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
-# license you chose for the specific language governing permissions and
-# limitations under that license.
-
-__all__ = [
-    'DetailStream'
-    ]
-
-from cStringIO import StringIO
-
-from fixtures import Fixture
-import testtools
-
-
-class DetailStream(Fixture):
-    """Provide a file-like object and expose it as a detail.
-
-    :attr stream: The file-like object.
-    """
-
-    def __init__(self, detail_name):
-        """Create a DetailStream.
-
-        :param detail_name: Use this as the name of the stream.
-        """
-        self._detail_name = detail_name
-
-    def setUp(self):
-        super(DetailStream, self).setUp()
-        self.stream = StringIO()
-        self.addDetail(self._detail_name,
-            testtools.content.content_from_stream(self.stream, seek_offset=0))
diff --git a/lib/fixtures/_fixtures/logger.py b/lib/fixtures/_fixtures/logger.py
index 0beb170..e46de3a 100644
--- a/lib/fixtures/_fixtures/logger.py
+++ b/lib/fixtures/_fixtures/logger.py
@@ -15,8 +15,10 @@
 
 from logging import StreamHandler, getLogger, INFO, Formatter
 
+from testtools.compat import _u
+
 from fixtures import Fixture
-from fixtures._fixtures.detailstream import DetailStream
+from fixtures._fixtures.streams import StringStream
 
 __all__ = [
     'FakeLogger',
@@ -88,8 +90,8 @@ class FakeLogger(Fixture):
 
     def setUp(self):
         super(FakeLogger, self).setUp()
-        name = u"pythonlogging:'%s'" % self._name
-        output = self.useFixture(DetailStream(name)).stream
+        name = _u("pythonlogging:'%s'") % self._name
+        output = self.useFixture(StringStream(name)).stream
         self._output = output
         handler = StreamHandler(output)
         if self._format:
@@ -100,7 +102,8 @@ class FakeLogger(Fixture):
 
     @property
     def output(self):
-        return self._output.getvalue()
+        self._output.seek(0)
+        return self._output.read()
 
 
 LoggerFixture = FakeLogger
diff --git a/lib/fixtures/_fixtures/streams.py b/lib/fixtures/_fixtures/streams.py
new file mode 100644
index 0000000..654ee67
--- /dev/null
+++ b/lib/fixtures/_fixtures/streams.py
@@ -0,0 +1,95 @@
+#  fixtures: Fixtures with cleanups for testing and convenience.
+#
+# Copyright (c) 2012, Robert Collins <robertc@robertcollins.net>
+#
+# Licensed under either the Apache License, Version 2.0 or the BSD 3-clause
+# license at the users choice. A copy of both licenses are available in the
+# project source as Apache-2.0 and BSD. You may not use this file except in
+# compliance with one of these two licences.
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under these licenses is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# license you chose for the specific language governing permissions and
+# limitations under that license.
+
+__all__ = [
+    'ByteStream',
+    'DetailStream',
+    'StringStream',
+    ]
+
+import io
+import sys
+
+from fixtures import Fixture
+import testtools
+
+
+class Stream(Fixture):
+    """Expose a file-like object as a detail.
+
+    :attr stream: The file-like object.
+    """
+
+    def __init__(self, detail_name, stream_factory):
+        """Create a ByteStream.
+
+        :param detail_name: Use this as the name of the stream.
+        :param stream_factory: Called to construct a pair of streams:
+            (write_stream, content_stream).
+        """
+        self._detail_name = detail_name
+        self._stream_factory = stream_factory
+
+    def setUp(self):
+        super(Stream, self).setUp()
+        write_stream, read_stream = self._stream_factory()
+        self.stream = write_stream
+        self.addDetail(self._detail_name,
+            testtools.content.content_from_stream(read_stream, seek_offset=0))
+
+
+def _byte_stream_factory():
+    result = io.BytesIO()
+    return (result, result)
+
+
+def ByteStream(detail_name):
+    """Provide a file-like object that accepts bytes and expose as a detail.
+
+    :param detail_name: The name of the detail.
+    :return: A fixture which has an attribute `stream` containing the file-like
+        object.
+    """
+    return Stream(detail_name, _byte_stream_factory)
+
+
+def _string_stream_factory():
+    lower = io.BytesIO()
+    upper = io.TextIOWrapper(lower, encoding="utf8")
+    # In theory, this is sufficient and correct, but on Python2,
+    # upper.write(_b('foo")) will whinge louadly.
+    if sys.version_info[0] < 3:
+        upper_write = upper.write
+        def safe_write(str_or_bytes):
+            if type(str_or_bytes) is str:
+                str_or_bytes = str_or_bytes.decode('utf8')
+            return upper_write(str_or_bytes)
+        upper.write = safe_write
+    return upper, lower
+
+
+def StringStream(detail_name):
+    """Provide a file-like object that accepts strings and expose as a detail.
+
+    :param detail_name: The name of the detail.
+    :return: A fixture which has an attribute `stream` containing the file-like
+        object.
+    """
+    return Stream(detail_name, _string_stream_factory)
+
+
+def DetailStream(detail_name):
+    """Deprecated alias for ByteStream."""
+    return ByteStream(detail_name)
diff --git a/lib/fixtures/fixture.py b/lib/fixtures/fixture.py
index 6c3422f..2cf966d 100644
--- a/lib/fixtures/fixture.py
+++ b/lib/fixtures/fixture.py
@@ -29,7 +29,7 @@ from testtools.compat import (
     )
 from testtools.helpers import try_import
 
-from callmany import (
+from fixtures.callmany import (
     CallMany,
     # Deprecated, imported for compatibility.
     MultipleExceptions,
diff --git a/lib/fixtures/tests/_fixtures/__init__.py b/lib/fixtures/tests/_fixtures/__init__.py
index 38987b9..e4d9403 100644
--- a/lib/fixtures/tests/_fixtures/__init__.py
+++ b/lib/fixtures/tests/_fixtures/__init__.py
@@ -15,7 +15,6 @@
 
 def load_tests(loader, standard_tests, pattern):
     test_modules = [
-        'detailstream',
         'environ',
         'logger',
         'monkeypatch',
@@ -23,6 +22,7 @@ def load_tests(loader, standard_tests, pattern):
         'popen',
         'pythonpackage',
         'pythonpath',
+        'streams',
         'tempdir',
         'temphomedir',
         'timeout',
diff --git a/lib/fixtures/tests/_fixtures/test_logger.py b/lib/fixtures/tests/_fixtures/test_logger.py
index c05e862..1f69459 100644
--- a/lib/fixtures/tests/_fixtures/test_logger.py
+++ b/lib/fixtures/tests/_fixtures/test_logger.py
@@ -16,7 +16,7 @@
 import logging
 
 from testtools import TestCase
-from cStringIO import StringIO
+from testtools.compat import StringIO
 
 from fixtures import (
     FakeLogger,
@@ -89,11 +89,22 @@ class FakeLoggerTest(TestCase, TestWithFixtures):
             # Output after getDetails is called is included.
             logging.info('some message')
             self.assertEqual("some message\n", content.as_text())
+        # The old content object returns the old usage after cleanUp (not
+        # strictly needed but convenient). Note that no guarantee is made that
+        # it will work after setUp is called again. [It does on Python 2.x, not
+        # on 3.x]
+        self.assertEqual("some message\n", content.as_text())
         with fixture:
-            # The old content object returns the old usage
-            self.assertEqual("some message\n", content.as_text())
-            # A new one returns the new output:
+            # A new one returns new output:
             self.assertEqual("", fixture.getDetails()[detail_name].as_text())
+        # The original content object may either fail, or return the old
+        # content (it must not have been reset..).
+        try:
+            self.assertEqual("some message\n", content.as_text())
+        except AssertionError:
+            raise
+        except:
+            pass
 
 
 class LogHandlerTest(TestCase, TestWithFixtures):
diff --git a/lib/fixtures/tests/_fixtures/test_detailstream.py b/lib/fixtures/tests/_fixtures/test_streams.py
index 9df351d..b4f4838 100644
--- a/lib/fixtures/tests/_fixtures/test_detailstream.py
+++ b/lib/fixtures/tests/_fixtures/test_streams.py
@@ -14,18 +14,33 @@
 # limitations under that license.
 
 from testtools import TestCase
+from testtools.compat import (
+    _b,
+    _u,
+    )
+from testtools.matchers import Contains
 
-from fixtures import DetailStream
+from fixtures import (
+    ByteStream,
+    DetailStream,
+    StringStream,
+    )
 
 
 class DetailStreamTest(TestCase):
 
+    def test_doc_mentions_deprecated(self):
+        self.assertThat(DetailStream.__doc__, Contains('Deprecated'))
+
+
+class TestByteStreams(TestCase):
+
     def test_empty_detail_stream(self):
         detail_name = 'test'
         fixture = DetailStream(detail_name)
         with fixture:
             content = fixture.getDetails()[detail_name]
-            self.assertEqual("", content.as_text())
+            self.assertEqual(_u(""), content.as_text())
 
     def test_stream_content_in_details(self):
         detail_name = 'test'
@@ -34,7 +49,7 @@ class DetailStreamTest(TestCase):
             stream = fixture.stream
             content = fixture.getDetails()[detail_name]
             # Output after getDetails is called is included.
-            stream.write("testing 1 2 3")
+            stream.write(_b("testing 1 2 3"))
             self.assertEqual("testing 1 2 3", content.as_text())
 
     def test_stream_content_reset(self):
@@ -43,12 +58,12 @@ class DetailStreamTest(TestCase):
         with fixture:
             stream = fixture.stream
             content = fixture.getDetails()[detail_name]
-            stream.write("testing 1 2 3")
+            stream.write(_b("testing 1 2 3"))
         with fixture:
             # The old content object returns the old usage
-            self.assertEqual("testing 1 2 3", content.as_text())
+            self.assertEqual(_u("testing 1 2 3"), content.as_text())
             content = fixture.getDetails()[detail_name]
             # A new fixture returns the new output:
             stream = fixture.stream
-            stream.write("1 2 3 testing")
-            self.assertEqual("1 2 3 testing", content.as_text())
+            stream.write(_b("1 2 3 testing"))
+            self.assertEqual(_u("1 2 3 testing"), content.as_text())