Use importlib instead of imp

snapshottest/module.py

@@ -1,7 +1,8 @@
 import codecs
 import errno
 import os
-import imp
+import sys
+import importlib.util
 from collections import defaultdict
 import logging
 
@@ -17,6 +18,28 @@ def _escape_quotes(text):
     return text.replace("'", "\\'")
 
 
+def _load_source(module_name, filepath):
+    """
+    Replaces old imp.load_source() call.
+
+    The imp module was dropped in Python 3.12 in favor of the importlib.
+    See: https://docs.python.org/3.11/library/imp.html#imp.load_module
+
+    Following code was inspired by the importlib documentation example: 
+    https://docs.python.org/3.12/library/importlib.html#importing-a-source-file-directly
+
+    This approach has been also encouraged in the official mailing lists:
+    https://discuss.python.org/t/how-do-i-migrate-from-imp/27885 
+    """
+    spec = importlib.util.spec_from_file_location(module_name, filepath)
+    module = importlib.util.module_from_spec(spec)
+    # As a performance optimization, store loaded module for further use.
+    # https://docs.python.org/3.11/library/sys.html#sys.modules
+    sys.modules[module_name] = module
+    spec.loader.exec_module(module)
+    return module
+
+
 class SnapshotModule(object):
     _snapshot_modules = {}
 
@@ -33,7 +56,7 @@ def __init__(self, module, filepath):
 
     def load_snapshots(self):
         try:
-            source = imp.load_source(self.module, self.filepath)
+            source = _load_source(self.module, self.filepath)
         # except FileNotFoundError:  # Python 3
         except (IOError, OSError) as err:
             if err.errno == errno.ENOENT: