Drop the limited support of tox 3.13 and 3.14 (due to Fedora 31 EOL)

.github/workflows/main.yaml

@@ -21,8 +21,8 @@ jobs:
         tox_env:
         # This information is repeated in tox.ini
         # (see https://github.com/fedora-python/tox-github-action/issues/8)
-        - py36-tox313
-        - py37-tox313
+        - py36-tox315
+        - py37-tox315
         - py38-tox315
         - py39-tox315
 

setup.py

@@ -19,11 +19,7 @@ setup(
     packages=find_packages("src"),
     entry_points={"tox": ["current-env = tox_current_env.hooks"]},
     install_requires=[
-        # We support tox 3.13 only to support Fedora 31.
-        # Fedora's tox 3.13 is patched to support Python 3.8 and 3.9,
-        # but the one downloaded from PyPI isn't and it doesn't work properly.
-        "tox>=3.15; python_version >= '3.8'",
-        "tox>=3.13; python_version < '3.8'",
+        "tox>=3.15",
         "importlib_metadata; python_version < '3.8'"
     ],
     python_requires=">=3.6",

tests/test_integration.py

@@ -10,8 +10,6 @@ import warnings
 import configparser
 import contextlib
 
-from packaging import version
-
 import pytest
 
 
@@ -97,10 +95,6 @@ def is_available(python):
     return True
 
 
-TOX_VERSION = version.parse(tox("--version").stdout.split(" ")[0])
-TOX313 = TOX_VERSION < version.parse("3.14")
-
-
 needs_py36789 = pytest.mark.skipif(
     not all((is_available(f"python3.{x}") for x in range(6, 10))),
     reason="This test needs python3.6, 3.7, 3.8 and 3.9 available in $PATH",
@@ -398,11 +392,6 @@ def test_regular_run():
     assert "/.tox/py39 is the exec_prefix" in lines[3]
     assert "congratulations" in result.stdout
     for y in 6, 7, 8, 9:
-        if TOX313 and y > 8:
-            # there is a bug in tox < 3.14,
-            # it creates venv with /usr/bin/python3 if the version is unknown
-            # See https://src.fedoraproject.org/rpms/python-tox/pull-request/15
-            continue
         for pkg in "py", "six", "test":
             sitelib = DOT_TOX / f"py3{y}/lib/python3.{y}/site-packages"
             assert sitelib.is_dir()

tox.ini

@@ -2,14 +2,13 @@
 
 # This information is repeated in .github/workflows/main.yaml
 # (see https://github.com/fedora-python/tox-github-action/issues/8)
-envlist = {py36,py37,py38,py39}-tox{release,master},{py36,py37}-tox313,{py38,py39}-tox315
+envlist = {py36,py37,py38,py39}-tox{release,master,tox315}
 
 [testenv]
 deps=
     pytest
     pytest-xdist
     packaging
-    tox313: tox >=3.13,<3.14
     tox315: tox >=3.15,<3.16
     toxrelease: tox
     toxmaster: git+https://github.com/tox-dev/tox.git@master