got pip_repository test passing

Author: rickeylev

examples/pip_repository_annotations/.bazelrc

@@ -5,4 +5,5 @@ try-import %workspace%/user.bazelrc
 # is in examples/bzlmod as the `whl_mods` feature.
 common --noenable_bzlmod
 common --enable_workspace
+common --legacy_external_runfiles=false
 common --incompatible_python_disallow_native_rules

examples/pip_repository_annotations/pip_repository_annotations_test.py

@@ -21,13 +21,7 @@
 import unittest
 from pathlib import Path
 
-print("sys.path:")
-for i, x in enumerate(sorted(sys.path)):
-    print(x)
-
-raise SystemExit(1)
-
-from rules_python.python.runfiles import runfiles
+from python.runfiles import runfiles
 
 
 class PipRepositoryAnnotationsTest(unittest.TestCase):
@@ -41,7 +35,7 @@ def wheel_pkg_dir(self) -> str:
     def test_build_content_and_data(self):
         r = runfiles.Create()
         rpath = r.Rlocation(
-            "pip_repository_annotations_example/external/{}/generated_file.txt".format(
+            "{}/generated_file.txt".format(
                 self.wheel_pkg_dir()
             )
         )
@@ -54,7 +48,7 @@ def test_build_content_and_data(self):
     def test_copy_files(self):
         r = runfiles.Create()
         rpath = r.Rlocation(
-            "pip_repository_annotations_example/external/{}/copied_content/file.txt".format(
+            "{}/copied_content/file.txt".format(
                 self.wheel_pkg_dir()
             )
         )
@@ -67,7 +61,7 @@ def test_copy_files(self):
     def test_copy_executables(self):
         r = runfiles.Create()
         rpath = r.Rlocation(
-            "pip_repository_annotations_example/external/{}/copied_content/executable{}".format(
+            "{}/copied_content/executable{}".format(
                 self.wheel_pkg_dir(),
                 ".exe" if platform.system() == "windows" else ".py",
             )
@@ -88,7 +82,7 @@ def test_data_exclude_glob(self):
         current_wheel_version = "0.38.4"
 
         r = runfiles.Create()
-        dist_info_dir = "pip_repository_annotations_example/external/{}/site-packages/wheel-{}.dist-info".format(
+        dist_info_dir = "{}/site-packages/wheel-{}.dist-info".format(
             self.wheel_pkg_dir(),
             current_wheel_version,
         )
@@ -119,11 +113,10 @@ def test_extra(self):
         # This test verifies that annotations work correctly for pip packages with extras
         # specified, in this case requests[security].
         r = runfiles.Create()
-        rpath = r.Rlocation(
-            "pip_repository_annotations_example/external/{}/generated_file.txt".format(
-                self.requests_pkg_dir()
-            )
+        path = "{}/generated_file.txt".format(
+            self.requests_pkg_dir()
         )
+        rpath = r.Rlocation(path)
         generated_file = Path(rpath)
         self.assertTrue(generated_file.exists())
 

python/private/site_init_template.py

@@ -124,6 +124,11 @@ def _search_path(name):
     return None
 
 
+# NOTE: We do not add _RUNFILES_ROOT to sys.path for two reasons:
+# 1. Under workspace, it makes every external repository importable. If a Bazel
+#    repository matches a Python import name, they conflict.
+# 2. Under bzlmod, the repo names in the runfiles directory aren't importable
+#    Python names, so there's no point in adding the runfiles root to sys.path.
 def _setup_sys_path():
     seen = set(sys.path)
     python_path_entries = []

python/runfiles/BUILD.bazel

@@ -36,6 +36,18 @@ py_library(
         ## todo: this fixes the test, but I don't think its generally safe to do.
         ## It adds the runfiles root, which makes _everything_ under it importable,
         ## not just the rules_python directory
+        ##
+        ## What's happening is bootstrap=script isn't adding runfiles to the root.
+        ## This is probably because of bzlmod: the directory names of the repos
+        ## are mangled, so aren't usable anyways, so why add it to create such
+        ## a reliance?
+        ##
+        ## Ideally, we would have a directory where only specific sub-directories (e.g
+        ## rules_python) existed. There's nowhere in runfiles that naturally has that
+        # though. The closest would be the venv's site-package directory, i.e. creating
+        # a rules_python dir that symlinks back. This could be done using the
+        # site_packages_symlinks.
+        #
         ##"../../..",
     ],
     visibility = ["//visibility:public"],