One last desperate attempt to cling on to Python 2.6 :-P

Author: xolox

Makefile

@@ -1,7 +1,7 @@
 # Makefile for the `rotate-backups' package.
 #
 # Author: Peter Odding <peter@peterodding.com>
-# Last Change: March 25, 2018
+# Last Change: August 2, 2018
 # URL: https://github.com/xolox/python-rotate-backups
 
 PACKAGE_NAME = rotate-backups
@@ -41,7 +41,8 @@ reset:
 	$(MAKE) install
 
 check: install
-	@scripts/check-code-style.sh
+	@pip-accel install --upgrade --quiet --requirement=requirements-checks.txt
+	@flake8
 
 test: install
 	@pip-accel install --quiet --requirement=requirements-tests.txt

constraints.txt

@@ -0,0 +1,24 @@
+# This is a pip constraints file that is used to preserve Python 2.6
+# compatibility (on Travis CI). Why I'm still doing that in 2018 is
+# a good question, maybe simply to prove that I can :-P.
+
+# flake8 3.0.0 drops explicit support for Python 2.6:
+# http://flake8.pycqa.org/en/latest/release-notes/3.0.0.html
+flake8 < 3.0.0 ; python_version < '2.7'
+
+# flake8-docstrings 1.0.0 switches from pep257 to pydocstyle and I haven't been
+# able to find a combination of versions of flake8-docstrings and pydocstyle
+# that actually works on Python 2.6. Here's the changelog:
+# https://gitlab.com/pycqa/flake8-docstrings/blob/master/HISTORY.rst
+flake8-docstrings < 1.0.0 ; python_version < '2.7'
+
+# pyflakes 2.0.0 drops Python 2.6 compatibility:
+# https://github.com/PyCQA/pyflakes/blob/master/NEWS.txt
+pyflakes < 2.0.0 ; python_version < '2.7'
+
+# pytest 3.3 drops Python 2.6 compatibility:
+# https://docs.pytest.org/en/latest/changelog.html#pytest-3-3-0-2017-11-23
+pytest < 3.3 ; python_version < '2.7'
+
+# simpleeval 0.9.2 introduces syntax that's incompatible with Python 2.6.
+simpleeval < 0.9.2 ; python_version < '2.7'

requirements-checks.txt

@@ -1,4 +1,8 @@
 # Python packages required to run `make check'.
+
+# Enable Python version compatibility.
+--constraints=constraints.txt
+
 flake8 >= 2.6.0
 flake8-docstrings >= 0.2.8
 pyflakes >= 1.2.3

requirements-tests.txt

@@ -1,6 +1,7 @@
-pytest >= 3.0.7, < 3.3.0 ; python_version > '2.6'
-pytest-cov >= 2.2.1
+# Python packages required to run `make test'.
+
+# Enable Python version compatibility.
+--constraints=constraints.txt
 
-# pytest release 3.3 drops Python 2.6 compatibility:
-# https://docs.pytest.org/en/latest/changelog.html#pytest-3-3-0-2017-11-23
-pytest < 3.3 ; python_version < '2.7'
+pytest >= 3.0.7
+pytest-cov >= 2.2.1

requirements-travis.txt

@@ -1,4 +1,13 @@
+# Python packages required on Travis CI.
+
+# Enable Python version compatibility.
+--constraints=constraints.txt
+
+# Pull in the requirements for code style checks,
+# the test suite and installation requirements.
 --requirement=requirements-checks.txt
 --requirement=requirements-tests.txt
 --requirement=requirements.txt
+
+# Prepare to submit coverage data.
 coveralls

requirements.txt

@@ -1,11 +1,12 @@
+# Installation requirements (see also constraints.txt).
+
 coloredlogs >= 5.1
 executor >= 19.2
 humanfriendly >= 3.4
 naturalsort >= 1.4
 property-manager >= 2.3
 python-dateutil >= 2.2
-# simpleeval version 0.9.2 introduces syntax that is incompatible with Python 2.6.
-simpleeval >= 0.8.7, < 0.9.2
+simpleeval >= 0.8.7
 six >= 1.9.0
 update-dotdee >= 5.0
 verboselogs >= 1.5