Factor out build/test configuration from tox.ini file.

pyproject.toml

@@ -0,0 +1,3 @@
+[tool.black]
+line-length = 100
+skip-string-normalization = true

setup.cfg

@@ -1,2 +1,10 @@
 [metadata]
 description-file=README.md
+
+[tool:pytest]
+testpaths = tests
+addopts = --cov-report term-missing:skip-covered --cov=borgmatic --ignore=tests/end-to-end
+
+[flake8]
+ignore = E501,W503
+exclude = *.*/*

tox.ini

@@ -7,22 +7,20 @@ minversion = 3.10.0
 usedevelop = True
 deps = -rtest_requirements.txt
 whitelist_externals = sh
+install_command =
+    # temporary work around for https://github.com/pypa/pip/issues/6434
+    python -m pip install --no-use-pep517 {opts} {packages}
 commands =
-    py.test --cov-report term-missing:skip-covered --cov=borgmatic --ignore=tests/end-to-end \
-        tests []
+    pytest
     sh scripts/black
     flake8 .
 
 [testenv:black]
 basepython = python3.7
 commands =
-    black --skip-string-normalization --line-length 100 .
+    black .
 
 [testenv:end-to-end]
 deps = -rtest_requirements.txt
 commands =
-    py.test tests/end-to-end []
-
-[flake8]
-ignore = E501,W503
-exclude = *.*/*
+    pytest tests/end-to-end