Add support for 3.8 and update documentation to Python 3. (#110)

+ Test pure versions and docs in TravisCI.

.travis.yml

 language: python
+dist: xenial
 matrix:
     include:
         - os: linux
           python: 2.7
+        - name: 2.7-pure
+          os: linux
+          python: 2.7
+          env: PURE_PYTHON=1
         - os: linux
           python: 3.5
         - os: linux
@@ -14,8 +19,22 @@ matrix:
         - os: linux
           python: pypy3
         - os: linux
-          dist: xenial
           python: 3.7
+        - name: 3.7-pure
+          os: linux
+          python: 3.7
+          env: PURE_PYTHON=1
+        - os: linux
+          python: 3.8-dev
+        - name: docs
+          os: linux
+          python: 3.6
+          install:
+            - pip install -U -e .[docs]
+          script:
+            - sphinx-build -b html -d docs/_build/doctrees docs docs/_build/html
+            - sphinx-build -b doctest -d docs/_build/doctrees docs docs/_build/doctest
+          after_success:
         # It's important to use 'macpython' builds to get the least
         # restrictive wheel tag. It's also important to avoid
         # 'homebrew 3' because it floats instead of being a specific version.
@@ -50,8 +69,8 @@ before_install:
     - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then git clone https://github.com/MacPython/terryfy; fi
     - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then source terryfy/travis_tools.sh; fi
     - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then get_python_environment $TERRYFY_PYTHON venv; fi
-install:
     - pip install -U pip setuptools cffi wheel coverage coveralls
+install:
     - pip install -U -e .[test]
 script:
     - python --version

CHANGES.rst

@@ -4,7 +4,9 @@
 4.5.1 (unreleased)
 ------------------
 
-- Nothing changed yet.
+- Add support for Python 3.8a3.
+
+- Update documentation to Python 3.
 
 
 4.5.0 (2019-05-09)

docs/using.rst

@@ -46,10 +46,10 @@ The examples below use a stub data manager class, and its stub cache class:
    ...         self._mru = []
    ...     def mru(self, oid):
    ...         self._mru.append(oid)
-   >>> from zope.interface import implements
+   >>> from zope.interface import implementer
    >>> from persistent.interfaces import IPersistentDataManager
-   >>> class DM(object):
-   ...     implements(IPersistentDataManager)
+   >>> @implementer(IPersistentDataManager)
+   ... class DM(object):
    ...     def __init__(self):
    ...         self._cache = Cache()
    ...         self.registered = 0
@@ -117,7 +117,7 @@ it has not yet been assigned, its value is ``None``:
 
 .. doctest::
 
-   >>> print p._p_jar
+   >>> print(p._p_jar)
    None
 
 The :attr:`_p_oid` attribute is the :term:`object id`, a unique value
@@ -126,7 +126,7 @@ has not yet been associated with its :term:`jar`, its value is ``None``:
 
 .. doctest::
 
-   >>> print p._p_oid
+   >>> print(p._p_oid)
    None
 
 Without a data manager, modifying a persistent object has no effect on
@@ -376,10 +376,10 @@ The ``_p_serial`` attribute is not affected by calling setstate.
 
 .. doctest::
 
-   >>> p._p_serial = "00000012"
+   >>> p._p_serial = b"00000012"
    >>> p.__setstate__(p.__getstate__())
    >>> p._p_serial
-   '00000012'
+   b'00000012'
 
 
 Estimated Object Size

setup.py

@@ -95,6 +95,7 @@ setup(name='persistent',
           "Programming Language :: Python :: 3.5",
           "Programming Language :: Python :: 3.6",
           "Programming Language :: Python :: 3.7",
+          "Programming Language :: Python :: 3.8",
           "Programming Language :: Python :: Implementation :: CPython",
           "Programming Language :: Python :: Implementation :: PyPy",
           "Framework :: ZODB",

tox.ini

 [tox]
 envlist =
-    py27,py35,py36,py37,py27-pure,py27-pure-cffi,pypy,pypy3,coverage,docs
+    py27,py35,py36,py37,py37-pure,py38,py27-pure,py27-pure-cffi,pypy, pypy3,coverage,docs
 
 [testenv]
 deps =
@@ -20,20 +20,26 @@ basepython =
 setenv =
     PURE_PYTHON = 1
 
+[testenv:py37-pure]
+basepython =
+    python3.7
+setenv =
+    PURE_PYTHON = 1
+
 [testenv:coverage]
 usedevelop = true
 basepython =
     python3.6
 commands =
     coverage run -m zope.testrunner --test-path=.
-    coverage report --fail-under=93
+    coverage report --fail-under=100
 deps =
     {[testenv]deps}
     coverage
 
 [testenv:docs]
 basepython =
-    python2.7
+    python3.6
 commands =
     sphinx-build -b html -d docs/_build/doctrees docs docs/_build/html
     sphinx-build -b doctest -d docs/_build/doctrees docs docs/_build/doctest