symlink the whl to a zip file to work around extract limitations in older bazels

Author: aignas

python/private/internal_config_repo.bzl

@@ -32,6 +32,7 @@ config = struct(
   enable_pystar = True,
   enable_pipstar = {enable_pipstar},
   enable_deprecation_warnings = {enable_deprecation_warnings},
+  bazel_8_or_later = {bazel_8_or_later},
   bazel_9_or_later = {bazel_9_or_later},
   BuiltinPyInfo = getattr(getattr(native, "legacy_globals", None), "PyInfo", {builtin_py_info_symbol}),
   BuiltinPyRuntimeInfo = getattr(getattr(native, "legacy_globals", None), "PyRuntimeInfo", {builtin_py_runtime_info_symbol}),
@@ -107,6 +108,7 @@ def _internal_config_repo_impl(rctx):
         builtin_py_info_symbol = builtin_py_info_symbol,
         builtin_py_runtime_info_symbol = builtin_py_runtime_info_symbol,
         builtin_py_cc_link_params_provider = builtin_py_cc_link_params_provider,
+        bazel_8_or_later = str(bazel_major_version >= 8),
         bazel_9_or_later = str(bazel_major_version >= 9),
     ))
 

python/private/pypi/patch_whl.bzl

@@ -87,6 +87,8 @@ def patch_whl(rctx, *, python_interpreter, whl_path, patches, **kwargs):
     # symlink to a zip file to use bazel's extract so that we can use bazel's
     # repository_ctx patch implementation. The whl file may be in a different
     # external repository.
+    #
+    # TODO @aignas 2025-11-24: remove this symlinking workaround when we drop support for bazel 7
     whl_file_zip = whl_input.basename + ".zip"
     rctx.symlink(whl_input, whl_file_zip)
     rctx.extract(whl_file_zip)

python/private/pypi/whl_library.bzl

@@ -377,10 +377,17 @@ def _whl_library_impl(rctx):
     #
     # Remove non-pipstar and config_load check when we release rules_python 2.
     if enable_pipstar:
+        if rp_config.bazel_8_or_later:
+            extract_path = whl_path
+        else:
+            extract_path = rctx.path(whl_path.basename + ".zip")
+            rctx.symlink(whl_path, extract_path)
         rctx.extract(
-            archive = whl_path,
+            archive = extract_path,
             output = "site-packages",
         )
+        if not rp_config.bazel_8_or_later:
+            rctx.delete(extract_path)
 
         metadata = whl_metadata(
             install_dir = whl_path.dirname.get_child("site-packages"),