Add preliminary support for Python 3.9 (#16)

* Adapt tests to Python 3.9.
* Drop support for Python 3.5 as its sunset is in some months.

7 files changed, 14 insertions, 18 deletions

diff --git a/.travis.yml b/.travis.yml
index bfeef7d..73fd48b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,11 +1,12 @@
 language: python
 python:
   - 2.7
-  - 3.5
   - 3.6
   - 3.7
   - 3.8
+  - 3.9-dev
   - pypy
+  - pypy3
 jobs:
   include:
     - name: flake8
diff --git a/CHANGES.rst b/CHANGES.rst
index 9246e3d..f61c05b 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,9 +5,9 @@
 4.4 (unreleased)
 ================
 
-- Add support for Python 3.8.
+- Add support for Python 3.8 and preliminary support for 3.9b4.
 
-- Drop support for Python 3.4.
+- Drop support for Python 3.4 and 3.5.
 
 
 4.3 (2018-10-04)
diff --git a/setup.cfg b/setup.cfg
index 2bece89..2a9acf1 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,13 +1,2 @@
-[nosetests]
-nocapture=1
-cover-package=zope.exceptions
-cover-erase=1
-with-doctest=0
-where=src
-
-[aliases]
-dev = develop easy_install zope.exceptions[testing]
-docs = easy_install zope.exceptions[docs]
-
 [bdist_wheel]
 universal = 1
diff --git a/setup.py b/setup.py
index c7282d6..a2306e2 100644
--- a/setup.py
+++ b/setup.py
@@ -64,7 +64,6 @@ setup(
         'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
diff --git a/src/zope/exceptions/log.py b/src/zope/exceptions/log.py
index 657ea7b..d5a6c30 100644
--- a/src/zope/exceptions/log.py
+++ b/src/zope/exceptions/log.py
@@ -19,7 +19,7 @@ import io
 
 from zope.exceptions.exceptionformatter import print_exception
 
-Buffer = io.StringIO if bytes is not str else io.BytesIO
+Buffer = io.StringIO if bytes is not str else io.BytesIO  # PY2
 
 
 class Formatter(logging.Formatter):
diff --git a/src/zope/exceptions/tests/test_exceptionformatter.py b/src/zope/exceptions/tests/test_exceptionformatter.py
index 23afe12..64729b1 100644
--- a/src/zope/exceptions/tests/test_exceptionformatter.py
+++ b/src/zope/exceptions/tests/test_exceptionformatter.py
@@ -17,6 +17,9 @@ import unittest
 import sys
 
 
+IS_PY39_OR_GREATER = sys.version_info >= (3, 9)
+
+
 class TextExceptionFormatterTests(unittest.TestCase):
 
     def _getTargetClass(self):
@@ -725,7 +728,11 @@ class Test_format_exception(unittest.TestCase):
             </p>""").format(
                 module='zope.exceptions.tests.test_exceptionformatter',
                 fn='test_format_exception_as_html',
-            )
+        )
+        if IS_PY39_OR_GREATER:  # pragma: no cover
+            # Python 3.9 moves the pointer after the statement instead to the
+            # last character of it:
+            expected = expected.replace('^<br />', ' ^<br />')
         # HTML formatter uses Windows line endings for some reason.
         result = result.replace('\r\n', '\n')
         result = re.sub(r'line \d\d\d,', 'line ABC,', result)
diff --git a/tox.ini b/tox.ini
index 88fa8b6..4241e47 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 envlist =
-    py27,py35,py36,py37,py38,pypy,pypy3,coverage,docs
+    flake8,py27,py36,py37,py38,py39,pypy,pypy3,coverage,docs
 
 [testenv]
 commands =