verify_distribution: Stop setting TERMINFO_DIRS and TCL_LIBRARY

In #215 we started setting the standard terminfo directories by default
and in #421 we taught Tcl to find its own install directory without
setting environment variables. Stop setting these environment variables
in tests to more closely match how users will use our builds.

Author: geofft

src/verify_distribution.py

@@ -6,36 +6,6 @@
 import sys
 import unittest
 
-TERMINFO_DIRS = [
-    "/etc/terminfo",
-    "/lib/terminfo",
-    "/usr/share/terminfo",
-]
-
-TCL_PATHS = [
-    # POSIX
-    ("lib", "tcl", "tcl"),
-    # Windows.
-    ("tcl",),
-]
-
-HERE = os.path.dirname(sys.executable)
-INSTALL_ROOT = os.path.dirname(HERE)
-
-# Need to set TCL_LIBRARY so local tcl/tk files get picked up.
-for parts in TCL_PATHS:
-    candidate = os.path.join(INSTALL_ROOT, *parts)
-
-    if os.path.exists(candidate):
-        os.environ["TCL_LIBRARY"] = candidate
-        break
-
-# Need to set TERMINFO_DIRS so terminfo database can be located.
-if "TERMINFO_DIRS" not in os.environ:
-    terminfo_dirs = [p for p in TERMINFO_DIRS if os.path.exists(p)]
-    if terminfo_dirs:
-        os.environ["TERMINFO_DIRS"] = ":".join(terminfo_dirs)
-
 
 class TestPythonInterpreter(unittest.TestCase):
     def test_compression(self):
@@ -68,7 +38,7 @@ def error_handler(fif, message):
     def test_curses_import(self):
         import curses
 
-        assert curses is not None
+        self.assertIsNotNone(curses)
 
     @unittest.skipIf(os.name == "nt", "curses not available on Windows")
     @unittest.skipIf("TERM" not in os.environ, "TERM not set")
@@ -165,7 +135,6 @@ def test_gil_disabled(self):
 
         self.assertEqual(sysconfig.get_config_var("Py_GIL_DISABLED"), wanted)
 
-    @unittest.skipIf("TCL_LIBRARY" not in os.environ, "TCL_LIBRARY not set")
     @unittest.skipIf("DISPLAY" not in os.environ, "DISPLAY not set")
     def test_tkinter(self):
         import tkinter as tk