Enable more tests

Author: slozier

Src/IronPythonTest/Cases/CPythonCasesManifest.ini

@@ -1215,6 +1215,9 @@ Ignore=true # AssertionError: 5 != 4
 [CPython.test_grammar]
 Ignore=true # blocked by https://github.com/IronLanguages/ironpython3/issues/98
 
+[CPython.test_gzip]
+IsolationLevel=PROCESS # https://github.com/IronLanguages/ironpython3/issues/1440
+
 [CPython.test_hashlib]
 Ignore=true # AttributeError: 'module' object has no attribute 'shake_128'
 
@@ -1227,6 +1230,9 @@ Ignore=true # two failures
 [CPython.test_list]
 Ignore=true # blocking
 
+[CPython.test_macpath]
+IsolationLevel=PROCESS # https://github.com/IronLanguages/ironpython3/issues/1440
+
 [CPython.test_math]
 Ignore=true # precision?
 

Src/IronPythonTest/Cases/IronPythonCasesManifest.ini

@@ -177,7 +177,7 @@ Ignore=true
 Ignore=true # test_doc
 
 [IronPython.test_builtin_stdlib]
-Ignore=true # NameError: name 'ModuleNotFoundError' is not defined / multiple other things
+Ignore=true # multiple failures
 
 [IronPython.test_codecs_stdlib]
 Ignore=true # multiple failures

Src/StdLib/Lib/test/support/script_helper.py

@@ -39,6 +39,11 @@ def interpreter_requires_environment():
     """
     global __cached_interp_requires_environment
     if __cached_interp_requires_environment is None:
+        # https://github.com/IronLanguages/ironpython3/issues/1440
+        if sys.implementation.name == "ironpython":
+            __cached_interp_requires_environment = True
+            return True
+
         # If PYTHONHOME is set, assume that we need it
         if 'PYTHONHOME' in os.environ:
             __cached_interp_requires_environment = True

Src/StdLib/Lib/test/test_slice.py

@@ -247,6 +247,7 @@ class myobj(): pass
         o = myobj()
         o.s = slice(o)
         w = weakref.ref(o)
+        del o # ironpython: for whatever reason setting to None is not enough on .NET Framework...
         o = None
         support.gc_collect()
         self.assertIsNone(w())

Tests/test_file.py

@@ -687,7 +687,7 @@ def test_errors(self):
 
         with self.assertRaises(OSError) as cm:
             open('path_too_long' * 100)
-        self.assertEqual(cm.exception.errno, (36 if is_posix else 22) if is_netcoreapp and not is_posix or sys.version_info >= (3,6) else 2)
+        self.assertEqual(cm.exception.errno, (36 if is_posix else 22) if is_netcoreapp and not is_posix or not is_cli and sys.version_info >= (3,6) else 2)
 
     def test_write_bytes(self):
         fname = self.temp_file