adjust the code so that the experimental_target_platforms is set in download_only case

Author: aignas

docs/pypi-dependencies.md

@@ -348,12 +348,6 @@ pip.parse(
         "requirements.linux_x86_64.txt": "linux_x86_64",
         "requirements.osx_aarch64.txt": "osx_aarch64",
     },
-    # We need to set these values to ensure that the METADATA is
-    # correctly parsed after downloading wheels.
-    experimental_target_platforms = [
-        "cp39_linux_x86_64",
-        "cp39_osx_aarch64",
-    ],
 )
 ```
 

examples/bzlmod/MODULE.bazel.lock

@@ -323,9 +323,12 @@ def _create_whl_repos(
             if get_index_urls:
                 logger.warn(lambda: "falling back to pip for installing the right file for {}".format(requirement.requirement_line))
 
-            whl_library_args["requirement"] = requirement.requirement_line
+            args = dict(whl_library_args.items())  # make a copy
+            args["requirement"] = requirement.requirement_line
             if requirement.extra_pip_args:
-                whl_library_args["extra_pip_args"] = requirement.extra_pip_args
+                args["extra_pip_args"] = requirement.extra_pip_args
+            if pip_attr.download_only:
+                args.setdefault("experimental_target_platforms", requirement.target_platforms)
 
             repo_name = "{}_{}".format(pip_name, whl_name)
             if len(requirements) > 1:
@@ -334,7 +337,7 @@ def _create_whl_repos(
                     for p in requirement.target_platforms
                 ])))
 
-            whl_libraries[repo_name] = dict(whl_library_args.items())
+            whl_libraries[repo_name] = args
             whl_map.setdefault(whl_name, []).append(
                 whl_alias(
                     repo = repo_name,

python/private/pypi/extension.bzl

@@ -321,6 +321,7 @@ simple==0.0.3 --hash=sha256:deadbaaf
         "pypi_315_extra": {
             "dep_template": "@pypi//{name}:{target}",
             "download_only": True,
+            "experimental_target_platforms": ["cp315_linux_x86_64"],
             "extra_pip_args": ["--platform=manylinux_2_17_x86_64", "--python-version=315", "--implementation=cp", "--abi=cp315"],
             "python_interpreter_target": "unit_test_interpreter_target",
             "repo": "pypi_315",
@@ -329,6 +330,7 @@ simple==0.0.3 --hash=sha256:deadbaaf
         "pypi_315_simple__linux_x86_64": {
             "dep_template": "@pypi//{name}:{target}",
             "download_only": True,
+            "experimental_target_platforms": ["cp315_linux_x86_64"],
             "extra_pip_args": ["--platform=manylinux_2_17_x86_64", "--python-version=315", "--implementation=cp", "--abi=cp315"],
             "python_interpreter_target": "unit_test_interpreter_target",
             "repo": "pypi_315",
@@ -337,6 +339,7 @@ simple==0.0.3 --hash=sha256:deadbaaf
         "pypi_315_simple__osx_aarch64": {
             "dep_template": "@pypi//{name}:{target}",
             "download_only": True,
+            "experimental_target_platforms": ["cp315_osx_aarch64"],
             "extra_pip_args": ["--platform=macosx_10_9_arm64", "--python-version=315", "--implementation=cp", "--abi=cp315"],
             "python_interpreter_target": "unit_test_interpreter_target",
             "repo": "pypi_315",