diff --git a/Lib/idlelib/CallTips.py b/Lib/idlelib/CallTips.py
--- a/Lib/idlelib/CallTips.py
+++ b/Lib/idlelib/CallTips.py
@@ -264,4 +264,7 @@
     print("%d of %d tests failed" % (num_fail, num_tests))
 
 if __name__ == '__main__':
-    main()
+    #main()
+    from unittest import main
+    from idlelib.Itest import test_calltips as t
+    main(t, verbosity=2, exit=False)
diff --git a/Lib/idlelib/Itest/@template.txt b/Lib/idlelib/Itest/@template.txt
new file mode 100644
--- /dev/null
+++ b/Lib/idlelib/Itest/@template.txt
@@ -0,0 +1,24 @@
+# Cut and paste template for Itest/test_x.py.
+# There are 3 blanks to fill after '.'. 'as', and '_'.
+
+import unittest
+import idlelib. as 
+
+class Test(unittest.TestCase):
+
+    def test_(self):
+
+
+if __name__ == '__main__':
+    unittest.main()
+
+# Template for running test_x.py from x.py, especially with ^F5 from editor.
+# There is only one blank to fill, 'x' after 'test_'.
+
+if __name__ == "__main__":
+    from unittest import main
+    from idlelib.Itest import test_ as t
+    main(t, verbosity=2, exit=False)
+
+# verbosity=2 lists all test_y methods
+# exit=False avoids spurious sys.exit traceback when running in Idle.
\ No newline at end of file
diff --git a/Lib/idlelib/Itest/__init__.py b/Lib/idlelib/Itest/__init__.py
new file mode 100644
--- /dev/null
+++ b/Lib/idlelib/Itest/__init__.py
@@ -0,0 +1,9 @@
+from os.path import dirname
+
+def load_tests(loader, standard_tests, pattern):
+    this_dir = dirname(__file__)
+    top_dir = dirname(dirname(this_dir))
+    package_tests = loader.discover(start_dir=this_dir, pattern='test*.py',
+                                    top_level_dir=top_dir)
+    standard_tests.addTests(package_tests)
+    return standard_tests
diff --git a/Lib/idlelib/Itest/test_calltips.py b/Lib/idlelib/Itest/test_calltips.py
new file mode 100644
--- /dev/null
+++ b/Lib/idlelib/Itest/test_calltips.py
@@ -0,0 +1,11 @@
+import unittest
+import idlelib.CallTips as ct
+
+class Test_get_entity(unittest.TestCase):
+    def test_bad_entity(self):
+        self.assertIsNone(ct.get_entity('1/0'))
+    def test_good_entity(self):
+        self.assertIs(ct.get_entity('int'), int)
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/Lib/idlelib/Itest/test_pathbrowser.py b/Lib/idlelib/Itest/test_pathbrowser.py
new file mode 100644
--- /dev/null
+++ b/Lib/idlelib/Itest/test_pathbrowser.py
@@ -0,0 +1,15 @@
+import unittest
+import idlelib.PathBrowser as PathBrowser
+
+class PathBrowserTest(unittest.TestCase):
+
+    def test_DirBrowserTreeItem(self):
+        # Issue16226 - make sure that getting a sublist works
+        try:
+            d = PathBrowser.DirBrowserTreeItem('')
+            d.GetSubList()
+        except Exception:
+            self.fail('')
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/Lib/idlelib/PathBrowser.py b/Lib/idlelib/PathBrowser.py
--- a/Lib/idlelib/PathBrowser.py
+++ b/Lib/idlelib/PathBrowser.py
@@ -95,4 +95,6 @@
         mainloop()
 
 if __name__ == "__main__":
-    main()
+    from unittest import main
+    from idlelib.Itest import test_pathbrowser as t
+    main(t, verbosity=2, exit=False)
diff --git a/Lib/test/test_idle.py b/Lib/test/test_idle.py
new file mode 100644
--- /dev/null
+++ b/Lib/test/test_idle.py
@@ -0,0 +1,5 @@
+from test import support
+# Skip test if tkinter wasn't built or idlelib deleted.
+support.import_module('tkinter')
+import unittest
+unittest.main(support.import_module('idlelib.Itest'))