XXX: proto.py use freezegun, as RELATIVE_BASE seem to cause issues

prototype/proto.py

@@ -6,6 +6,7 @@ import time
 
 import dateparser
 import pytz
+import freezegun
 
 # this is golang's time.RFC3339
 rfc3339_format = "%Y-%m-%dT%H:%M:%SZ"
@@ -36,11 +37,14 @@ time.tzset()
 
 # process relative time
 if args.relative_time_base and args.relative_time_base != "now":
-    dateparser_settings["RELATIVE_BASE"] = datetime.datetime.strptime(
-        args.relative_time_base, rfc3339_format
-    ).replace(
+    # dateparsers' has a RELATIVE_BASE option for this, but this does not work well,
+    # this triggers some TypeError internally, so use freezetime to change
+    # time base.
+    freezegun.freeze_time(
+        datetime.datetime.strptime(
+            args.relative_time_base, rfc3339_format).replace(
                 tzinfo=pytz.utc  # the Z in our format means UTC
-    ).astimezone(pytz.timezone(args.timezone))
+            ).astimezone(pytz.timezone(args.timezone))).start()
 
 with open(args.formats, "r") as f:
     for line in f: