fix: Type error with YAML dates in frontmatter

When valid YAML dates or times are added to the page frontmatter, the
YAML parser will already convert them to datetime.date or
datetime.datetime objects.

Example:

    ---
    date: 2023-04-12
    ---

This resulted in #strptime raising a TypeError because datetime.date
isn't a string. This commit changes the plugin code to always accept a
native datetime.date or datetime.datetime, even if meta_time_format is
not set, and handle them without string parsing.

Close #48

mkdocs_blogging_plugin/plugin.py

@@ -1,15 +1,18 @@
-import os
 import logging
+import os
 import re
+from datetime import date, datetime
+from pathlib import Path
 from typing import Dict
+
+from jinja2 import Environment, FileSystemLoader, Template, select_autoescape
 from mkdocs.config import config_options
-from mkdocs.plugins import BasePlugin
 from mkdocs.exceptions import PluginError
-from jinja2 import Environment, FileSystemLoader, Template, select_autoescape
+from mkdocs.plugins import BasePlugin
+
 from mkdocs_blogging_plugin.config import BloggingConfig
+
 from .util import Util
-from pathlib import Path
-from datetime import datetime
 
 DIR_PATH = Path(os.path.dirname(os.path.realpath(__file__)))
 BLOG_PAGE_PATTERN = re.compile(
@@ -332,13 +335,10 @@ def generate_html(self, category) -> str:
 
     def with_timestamp(self, page, by_revision):
         timestamp = None
-        if self.meta_time_format:
-            if "time" in page.meta:
-                timestamp = datetime.strptime(
-                    page.meta["time"], self.meta_time_format).timestamp()
-            elif "date" in page.meta:
-                timestamp = datetime.strptime(
-                    page.meta["date"], self.meta_time_format).timestamp()
+        if "time" in page.meta:
+            timestamp = self._parse_time(page.meta["time"])
+        if "date" in page.meta and timestamp is None:
+            timestamp = self._parse_time(page.meta["date"])
         if not timestamp:
             timestamp = self.util.get_git_commit_timestamp(
                 page.file.abs_src_path, is_first_commit=(not by_revision))
@@ -347,3 +347,11 @@ def with_timestamp(self, page, by_revision):
             timestamp, False, format=self.time_format, _locale=self.locale)
 
         return page
+
+    def _parse_time(self, value):
+        if isinstance(value, datetime):
+            return value.timestamp()
+        if isinstance(value, date):
+            return datetime.combine(value, datetime.min.time()).timestamp()
+        if self.meta_time_format:
+            return datetime.strptime(value, self.meta_time_format).timestamp()

tests/test_format.py

@@ -1,8 +1,8 @@
-from datetime import datetime
+import datetime
 import os
+import unittest
 from pathlib import Path
 from types import SimpleNamespace
-import unittest
 
 from mkdocs_blogging_plugin.plugin import BloggingPlugin
 
@@ -29,12 +29,24 @@ def test_date(self):
         meta_date_str = "2022-05-03 11:09:00"
         page = SimpleNamespace(meta={"time": meta_date_str})
 
-        date = datetime.strptime(
+        date = datetime.datetime.strptime(
             meta_date_str, self.config["meta_time_format"])
 
         page = self.plugin.with_timestamp(page, False)
 
-        expected_output = datetime.strftime(
+        expected_output = datetime.datetime.strftime(
             date, self.config["time_format"])
 
         assert page.meta["localized-time"] == expected_output
+
+    def test_date_object(self):
+        page = SimpleNamespace(meta={"date": datetime.date(2023, 4, 12)})
+        page = self.plugin.with_timestamp(page, False)
+
+        assert page.meta["localized-time"] == "2023/04/12 00:00:00"
+
+    def test_datetime_object(self):
+        page = SimpleNamespace(meta={"date": datetime.datetime(2023, 4, 12, 9, 15, 30)})
+        page = self.plugin.with_timestamp(page, False)
+
+        assert page.meta["localized-time"] == "2023/04/12 09:15:30"