Clean up the platform constants in env.py

Author: nedbat

coverage/env.py

@@ -11,24 +11,25 @@
 WINDOWS = sys.platform == "win32"
 LINUX = sys.platform.startswith("linux")
 
+# Python implementations.
+CPYTHON = (platform.python_implementation() == "CPython")
+PYPY = (platform.python_implementation() == "PyPy")
+JYTHON = (platform.python_implementation() == "Jython")
+IRONPYTHON = (platform.python_implementation() == "IronPython")
+
 # Python versions. We amend version_info with one more value, a zero if an
 # official version, or 1 if built from source beyond an official version.
 PYVERSION = sys.version_info + (int(platform.python_version()[-1] == "+"),)
 PY2 = PYVERSION < (3, 0)
 PY3 = PYVERSION >= (3, 0)
 
-# Python implementations.
-PYPY = (platform.python_implementation() == 'PyPy')
 if PYPY:
     PYPYVERSION = sys.pypy_version_info
 
 PYPY2 = PYPY and PY2
 PYPY3 = PYPY and PY3
 
-JYTHON = (platform.python_implementation() == 'Jython')
-IRONPYTHON = (platform.python_implementation() == 'IronPython')
-
-# Python behavior
+# Python behavior.
 class PYBEHAVIOR(object):
     """Flags indicating this Python's behavior."""
 

tests/test_process.py

@@ -1099,7 +1099,7 @@ def excepthook(*args):
         self.assertEqual(line_counts(data)['excepthook.py'], 7)
 
     def test_excepthook_exit(self):
-        if env.PYPY or env.JYTHON:
+        if not env.CPYTHON:
             self.skipTest("non-CPython handles excepthook exits differently, punt for now.")
         self.make_file("excepthook_exit.py", """\
             import sys