have non-regex_match fallback for pre bazel 8

Author: rickeylev

python/private/venv_runfiles.bzl

@@ -215,6 +215,21 @@ def _merge_venv_path_group(ctx, group, keep_map):
             if venv_path not in keep_map:
                 keep_map[venv_path] = file
 
+def _is_importable_name(name):
+    # Requires Bazel 8+
+    if hasattr(py_internal, "regex_match"):
+        # ?U means activates unicode matching (Python allows most unicode
+        # in module names / identifiers).
+        # \w matches alphanumeric and underscore.
+        # NOTE: regex_match has an implicit ^ and $
+        return py_internal.regex_match(name, "(?U)\\w+")
+    else:
+        # Otherwise, use a rough hueristic that should catch most cases.
+        return (
+            "." not in name and
+            "-" not in name
+        )
+
 def get_venv_symlinks(ctx, files, package, version_str, site_packages_root):
     """Compute the VenvSymlinkEntry objects for a library.
 
@@ -304,7 +319,7 @@ def get_venv_symlinks(ctx, files, package, version_str, site_packages_root):
             # If its already known to be non-implicit namespace, then skip
             namespace_package_dirs.get(top_level_dirname, True) and
             # It must be an importable name to be an implicit namespace package
-            py_internal.regex_match(top_level_dirname, "(?U)\\w+")
+            _is_importable_name(top_level_dirname)
         ):
             namespace_package_dirs.setdefault(top_level_dirname, True)
 

tests/venv_site_packages_libs/app_files_building/app_files_building_tests.bzl

@@ -269,9 +269,11 @@ def _test_optimized_grouping_implicit_namespace_packages(name):
     empty_files(
         name = name + "_files",
         paths = [
-            "site-packages/namespace/part1/foo.py",
-            "site-packages/namespace/part2/bar.py",
-            "site-packages/namespace-1.0.dist-info/METADATA",
+            # NOTE: An alphanumeric name with underscores is used to verify
+            # name matching is correct.
+            "site-packages/name_space9/part1/foo.py",
+            "site-packages/name_space9/part2/bar.py",
+            "site-packages/name_space9-1.0.dist-info/METADATA",
         ],
     )
     analysis_test(
@@ -296,24 +298,24 @@ def _test_optimized_grouping_implicit_namespace_packages_impl(env, target):
     rr = "{}/{}/site-packages/".format(test_ctx.workspace_name, env.ctx.label.package)
     expected = [
         _venv_symlink(
-            "namespace/part1",
-            link_to_path = rr + "namespace/part1",
+            "name_space9/part1",
+            link_to_path = rr + "name_space9/part1",
             files = [
-                "tests/venv_site_packages_libs/app_files_building/site-packages/namespace/part1/foo.py",
+                "tests/venv_site_packages_libs/app_files_building/site-packages/name_space9/part1/foo.py",
             ],
         ),
         _venv_symlink(
-            "namespace/part2",
-            link_to_path = rr + "namespace/part2",
+            "name_space9/part2",
+            link_to_path = rr + "name_space9/part2",
             files = [
-                "tests/venv_site_packages_libs/app_files_building/site-packages/namespace/part2/bar.py",
+                "tests/venv_site_packages_libs/app_files_building/site-packages/name_space9/part2/bar.py",
             ],
         ),
         _venv_symlink(
-            "namespace-1.0.dist-info",
-            link_to_path = rr + "namespace-1.0.dist-info",
+            "name_space9-1.0.dist-info",
+            link_to_path = rr + "name_space9-1.0.dist-info",
             files = [
-                "tests/venv_site_packages_libs/app_files_building/site-packages/namespace-1.0.dist-info/METADATA",
+                "tests/venv_site_packages_libs/app_files_building/site-packages/name_space9-1.0.dist-info/METADATA",
             ],
         ),
     ]