Windows bugfix: path-to-URL conversion (spack#37827)

When interpreting local paths as relative URL endpoints, they were
formatted as Windows paths on Windows (i.e. with '\'). URLs should
always be POSIX-style.

lib/spack/spack/test/web.py

@@ -4,7 +4,6 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import collections
 import os
-import sys
 
 import pytest
 
@@ -34,7 +33,6 @@ def _create_url(relative_url):
 root_with_fragment = _create_url("index_with_fragment.html")
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 @pytest.mark.parametrize(
     "depth,expected_found,expected_not_found,expected_text",
     [
@@ -99,35 +97,30 @@ def test_spider_no_response(monkeypatch):
     assert not pages and not links
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_versions_of_archive_0():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=0)
     assert Version("0.0.0") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_versions_of_archive_1():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=1)
     assert Version("0.0.0") in versions
     assert Version("1.0.0") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_versions_of_archive_2():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=2)
     assert Version("0.0.0") in versions
     assert Version("1.0.0") in versions
     assert Version("2.0.0") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_exotic_versions_of_archive_2():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=2)
     # up for grabs to make this better.
     assert Version("2.0.0b2") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_versions_of_archive_3():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=3)
     assert Version("0.0.0") in versions
@@ -137,15 +130,13 @@ def test_find_versions_of_archive_3():
     assert Version("4.5") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_exotic_versions_of_archive_3():
     versions = spack.util.web.find_versions_of_archive(root_tarball, root, list_depth=3)
     assert Version("2.0.0b2") in versions
     assert Version("3.0a1") in versions
     assert Version("4.5-rc5") in versions
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_find_versions_of_archive_with_fragment():
     versions = spack.util.web.find_versions_of_archive(
         root_tarball, root_with_fragment, list_depth=0
@@ -206,7 +197,6 @@ def test_etag_parser():
     assert spack.util.web.parse_etag("abc def") is None
 
 
-@pytest.mark.skipif(sys.platform == "win32", reason="Not supported on Windows (yet)")
 def test_list_url(tmpdir):
     testpath = str(tmpdir)
     testpath_url = url_util.path_to_file_url(testpath)

lib/spack/spack/util/web.py

@@ -17,6 +17,7 @@
 import traceback
 import urllib.parse
 from html.parser import HTMLParser
+from pathlib import Path, PurePosixPath
 from urllib.error import URLError
 from urllib.request import HTTPSHandler, Request, build_opener
 
@@ -498,7 +499,8 @@ def list_url(url, recursive=False):
 
     if local_path:
         if recursive:
-            return list(_iter_local_prefix(local_path))
+            # convert backslash to forward slash as required for URLs
+            return [str(PurePosixPath(Path(p))) for p in list(_iter_local_prefix(local_path))]
         return [
             subpath
             for subpath in os.listdir(local_path)
@@ -738,7 +740,8 @@ def find_versions_of_archive(
 
         # We'll be a bit more liberal and just look for the archive
         # part, not the full path.
-        url_regex = os.path.basename(url_regex)
+        # this is a URL so it is a posixpath even on Windows
+        url_regex = PurePosixPath(url_regex).name
 
         # We need to add a / to the beginning of the regex to prevent
         # Spack from picking up similarly named packages like: