Merge pull request #10186 from uranusjr/new-resolver-file-link-localhost

news/10162.bugfix.rst

@@ -0,0 +1,2 @@
+New resolver: URL comparison logic now treats ``file://localhost/`` and
+``file:///`` as equivalent to conform to RFC 8089.

src/pip/_internal/models/link.py

@@ -260,6 +260,9 @@ class _CleanResult(NamedTuple):
     def from_link(cls, link: Link) -> "_CleanResult":
         parsed = link._parsed_url
         netloc = parsed.netloc.rsplit("@", 1)[-1]
+        # According to RFC 8089, an empty host in file: means localhost.
+        if parsed.scheme == "file" and not netloc:
+            netloc = "localhost"
         fragment = urllib.parse.parse_qs(parsed.fragment)
         if "egg" in fragment:
             logger.debug("Ignoring egg= fragment in %s", link)

tests/functional/test_new_resolver.py

@@ -1,4 +1,5 @@
 import os
+import pathlib
 import sys
 import textwrap
 
@@ -1962,3 +1963,49 @@ def test_new_resolver_transitively_depends_on_unnamed_local(script):
         certbot_apache="99.99.0.dev0",
         certbot_docs="1",
     )
+
+
+def _to_uri(path):
+    # Something like file:///path/to/package
+    return pathlib.Path(path).as_uri()
+
+
+def _to_localhost_uri(path):
+    # Something like file://localhost/path/to/package
+    return pathlib.Path(path).as_uri().replace("///", "//localhost/")
+
+
+@pytest.mark.parametrize(
+    "format_dep",
+    [
+        pytest.param(_to_uri, id="emptyhost"),
+        pytest.param(_to_localhost_uri, id="localhost"),
+    ],
+)
+@pytest.mark.parametrize(
+    "format_input",
+    [
+        pytest.param(lambda path: path, id="path"),
+        pytest.param(_to_uri, id="emptyhost"),
+        pytest.param(_to_localhost_uri, id="localhost"),
+    ],
+)
+def test_new_resolver_file_url_normalize(script, format_dep, format_input):
+    lib_a = create_test_package_with_setup(
+        script,
+        name="lib_a",
+        version="1",
+    )
+    lib_b = create_test_package_with_setup(
+        script,
+        name="lib_b",
+        version="1",
+        install_requires=[f"lib_a @ {format_dep(lib_a)}"],
+    )
+
+    script.pip(
+        "install",
+        "--no-cache-dir", "--no-index",
+        format_input(lib_a), lib_b,
+    )
+    script.assert_installed(lib_a="1", lib_b="1")