Restore original behavior, adjust test to match

I remember that the aim of this PR is to add a test demonstrating
the existing behavior. I do not intend to fix any possible problems
I encounter along the way, merely demonstrate them clearly in the
test, so that they may be fixed later, with a clear test in place.

Accordingly, I've removed my attempts to use consistent slashes in
each RSS items' GUID field, and instead adjusted the test to match
the current behavior. The test contains a TODO describing that I
suspect this behavior might be incorrect.

nikola/plugins/task/galleries.py

@@ -32,7 +32,6 @@
 import json
 import mimetypes
 import os
-import pathlib
 from collections import OrderedDict
 from urllib.parse import urljoin
 
@@ -738,10 +737,6 @@ def make_url(url):
         else:
             img_list, dest_img_list, img_titles = [], [], []
 
-        def forward_slashes(path):
-            """Given a path, convert directory separators to forward slash, on all platforms."""
-            return str(pathlib.PurePosixPath(*os.path.split(path)))
-
         items = []
         for img, srcimg, title in list(zip(dest_img_list, img_list, img_titles))[:self.kw["feed_length"]]:
             img_size = os.stat(
@@ -750,7 +745,7 @@ def forward_slashes(path):
             args = {
                 'title': title,
                 'link': make_url(img),
-                'guid': rss.Guid(forward_slashes(img), False),
+                'guid': rss.Guid(img, False),
                 'pubDate': self.image_date(srcimg),
                 'enclosure': rss.Enclosure(
                     make_url(img),

tests/integration/test_demo_build.py

@@ -73,9 +73,13 @@ def test_gallery_rss(build, output_dir):
     assert parsed.feed.subtitle == ''  # From the XML field 'description'
     assert parsed.feed.updated == rfc822(BUILDTIME)
     # and the images, as items in the RSS feed, are:
+    # TODO I think the id for each item should not contain platform-dependant slashes.
+    #      The id for an RSS item should perhaps always use forward slashes no matter
+    #      what platform we are on.
+    sep = os.path.sep
     expected_items = [
         dict(
-            id='galleries/demo/tesla4_lg.jpg',
+            id=f'galleries{sep}demo{sep}tesla4_lg.jpg',
             link='https://example.com/galleries/demo/tesla4_lg.jpg',
             links=[
                 Any(),
@@ -90,7 +94,7 @@ def test_gallery_rss(build, output_dir):
             title='Tesla4 lg',
         ),
         dict(
-            id='galleries/demo/tesla_conducts_lg.webp',
+            id=f'galleries{sep}demo{sep}tesla_conducts_lg.webp',
             link='https://example.com/galleries/demo/tesla_conducts_lg.webp',
             links=[
                 Any(),
@@ -105,7 +109,7 @@ def test_gallery_rss(build, output_dir):
             title='Tesla conducts lg',
         ),
         dict(
-            id='galleries/demo/tesla_lightning1_lg.jpg',
+            id=f'galleries{sep}demo{sep}tesla_lightning1_lg.jpg',
             link='https://example.com/galleries/demo/tesla_lightning1_lg.jpg',
             links=[
                 Any(),
@@ -120,7 +124,7 @@ def test_gallery_rss(build, output_dir):
             title='Tesla lightning1 lg',
         ),
         dict(
-            id='galleries/demo/tesla_lightning2_lg.jpg',
+            id=f'galleries{sep}demo{sep}tesla_lightning2_lg.jpg',
             link='https://example.com/galleries/demo/tesla_lightning2_lg.jpg',
             links=[
                 Any(),
@@ -135,7 +139,7 @@ def test_gallery_rss(build, output_dir):
             title='Tesla lightning2 lg',
         ),
         dict(
-            id='galleries/demo/tesla_tower1_lg.jpg',
+            id=f'galleries{sep}demo{sep}tesla_tower1_lg.jpg',
             link='https://example.com/galleries/demo/tesla_tower1_lg.jpg',
             links=[
                 Any(),