Force all CPython CI builds to require functioning C extensions, and …

…simplify tox.ini.

.travis.yml

@@ -5,6 +5,11 @@ env:
     - TWINE_USERNAME: zope.wheelbuilder
     # this sets $PYPIPASSWORD
     - secure: "NTWzDr5p8KRPNt+sniTot7csbzC87rzir/XfLtENE0GpQ49FlKw3lBhsDqAPoD8Ea5lwiHXmC/C/ci1UZhFvVEkAoQ2qJlMRnhqUdRJSrqcitmRt0fT6mLaTd+Lr+DxKlBxpssobrEm2G42V/G1s0Ggym04OqF8T+s6MF5ywgJM="
+    # We want to require the C extensions to build and function
+    # everywhere (except where we specifically opt-out, currently just
+    # PyPy, where they build but don't quite work).
+    - PURE_PYTHON: 0
+
 
 python:
   - 2.7
@@ -17,6 +22,12 @@ python:
 
 jobs:
   include:
+    # Don't test C extensions on PyPy.
+    - python: pypy
+      env: PURE_PYTHON=1
+
+    - python: pypy3
+      env: PURE_PYTHON=1
 
     # Special Linux builds
     - name: "Python: 2.7, pure (no C extensions)"
@@ -32,10 +43,6 @@ jobs:
       python: 3.7
       env: PURE_PYTHON=1
 
-    - name: "Python: 3.8, (forced C extensions)"
-      python: 3.7
-      env: PURE_PYTHON=0
-
     - name: "Documentation"
       python: 3.6
       install:

appveyor.yml

@@ -3,6 +3,7 @@ environment:
     TWINE_USERNAME: zope.wheelbuilder
     TWINE_PASSWORD:
       secure: UcdTh6W78cRLVGfKRFoa5A==
+    PURE_PYTHON: 0
 
   matrix:
     - python: 27

tox.ini

@@ -26,8 +26,8 @@ basepython =
     python3.6
 commands =
     coverage run -m zope.testrunner --test-path=.
-    python -c 'import os, subprocess; env = os.environ.copy(); env["PURE_PYTHON"] = "1"; subprocess.check_call("coverage run -a -m zope.testrunner --test-path=.", shell=True, env=env)'
-    python -c 'import os, subprocess; env = os.environ.copy(); env["PURE_PYTHON"] = "0"; subprocess.check_call("coverage run -a -m zope.testrunner --test-path=.", shell=True, env=env)'
+    python -c 'import os, subprocess; subprocess.check_call("coverage run -a -m zope.testrunner --test-path=.", env=dict(os.environ, PURE_PYTHON="1"), shell=True)'
+    python -c 'import os, subprocess; subprocess.check_call("coverage run -a -m zope.testrunner --test-path=.", env=dict(os.environ, PURE_PYTHON="0"), shell=True)'
     coverage report --fail-under=100
 deps =
     {[testenv]deps}