Add very simple test that confirms ModuleWatcher nominally functions

Author: dihm

labscript_utils/modulewatcher.py

@@ -138,3 +138,32 @@ def unload(self):
         # code holds references to sys.meta_path, and to preserve order, since order
         # is relevant.
         sys.meta_path[:] = self.meta_whitelist
+
+if __name__ == "__main__":
+
+    from pathlib import Path
+    import time
+
+    dict1 = {'t': 5, 'val': 10}
+    dict2 = {'t': 5, 'val': 11}
+
+    print('ModuleWatcher instatiated in debug mode')
+    module_watcher = ModuleWatcher(debug=True)
+
+    # import a local module
+    import labscript_utils.dict_diff
+    print('imported labscript_utils.dict_diff')
+    print(labscript_utils.dict_diff.dict_diff(dict1, dict2))
+    print('used dict_diff function, waiting 2 seconds for module watcher to update')
+    time.sleep(2)
+
+    # now pretend it has been updated
+    ex_mod = Path('dict_diff.py')
+    ex_mod.touch()
+    print('dict_diff module touched, waiting 2 seconds for ModuleWatcher to notice')
+    time.sleep(2)
+
+    print(labscript_utils.dict_diff.dict_diff(dict1, dict2))
+    print('Used dict_diff again, waiting 2 seconds for ModuleWatcher to not do anything')
+    time.sleep(2)
+