[DayOne] support moderm plistlib (#909)

The API of the standard library's `plistlib` changed with version 3.4 of Python, and the old API is being removed in Python 3.9. In other words, the new API is supported by all version of Python we current support (3.6 to 3.8).

See https://docs.python.org/3.4/library/plistlib.html for more details.

jrnl/DayOneJournal.py

@@ -8,6 +8,7 @@
 from datetime import datetime
 import time
 import fnmatch
+from pathlib import Path
 import plistlib
 import pytz
 import uuid
@@ -43,7 +44,7 @@ def open(self):
         for filename in filenames:
             with open(filename, "rb") as plist_entry:
                 try:
-                    dict_entry = plistlib.readPlist(plist_entry)
+                    dict_entry = plistlib.load(plist_entry, fmt=plistlib.FMT_XML)
                 except self.PLIST_EXCEPTIONS:
                     pass
                 else:
@@ -84,8 +85,10 @@ def write(self):
                 if not hasattr(entry, "uuid"):
                     entry.uuid = uuid.uuid1().hex
 
-                filename = os.path.join(
-                    self.config["journal"], "entries", entry.uuid.upper() + ".doentry"
+                fn = (
+                    Path(self.config["journal"])
+                    / "entries"
+                    / (entry.uuid.upper() + ".doentry")
                 )
 
                 entry_plist = {
@@ -99,7 +102,9 @@ def write(self):
                         for tag in entry.tags
                     ],
                 }
-                plistlib.writePlist(entry_plist, filename)
+                # plistlib expects a binary object
+                with fn.open(mode="wb") as f:
+                    plistlib.dump(entry_plist, f, fmt=plistlib.FMT_XML, sort_keys=False)
         for entry in self._deleted_entries:
             filename = os.path.join(
                 self.config["journal"], "entries", entry.uuid + ".doentry"