fix get_supported_tags in cases where the target env has a different platform (#10361)

Author: radoering

src/poetry/utils/env/script_strings.py

@@ -1,5 +1,29 @@
 from __future__ import annotations
 
+import packaging.tags
+
+
+GET_PLATFORMS = f"""
+import importlib.util
+import json
+import sys
+
+from pathlib import Path
+
+spec = importlib.util.spec_from_file_location(
+    "packaging", Path(r"{packaging.__file__}")
+)
+packaging = importlib.util.module_from_spec(spec)
+sys.modules[spec.name] = packaging
+
+spec = importlib.util.spec_from_file_location(
+    "packaging.tags", Path(r"{packaging.tags.__file__}")
+)
+packaging_tags = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(packaging_tags)
+
+print(json.dumps(list(packaging_tags.platform_tags())))
+"""
 
 GET_ENVIRONMENT_INFO = """\
 import json
@@ -61,6 +85,7 @@ def _version_nodot(version):
         implementation_name, implementation_name
     ),
     "interpreter_version": interpreter_version(),
+    "sysconfig_platform": sysconfig.get_platform(),
 }
 
 print(json.dumps(env))

src/poetry/utils/env/virtual_env.py

@@ -3,6 +3,7 @@
 import json
 import os
 import re
+import sysconfig
 
 from contextlib import contextmanager
 from copy import deepcopy
@@ -15,6 +16,7 @@
 from poetry.utils.env.script_strings import GET_BASE_PREFIX
 from poetry.utils.env.script_strings import GET_ENVIRONMENT_INFO
 from poetry.utils.env.script_strings import GET_PATHS
+from poetry.utils.env.script_strings import GET_PLATFORMS
 from poetry.utils.env.script_strings import GET_SYS_PATH
 
 
@@ -54,6 +56,7 @@ def get_supported_tags(self) -> list[Tag]:
         python = self.version_info[:3]
         interpreter_name = self.marker_env["interpreter_name"]
         interpreter_version = self.marker_env["interpreter_version"]
+        sysconfig_platform = self.marker_env["sysconfig_platform"]
 
         if interpreter_name == "pp":
             interpreter = "pp3"
@@ -62,9 +65,28 @@ def get_supported_tags(self) -> list[Tag]:
         else:
             interpreter = None
 
+        # Why using sysconfig.get_platform() and not ...
+        # ... platform.machine()
+        #  This one is also different for x86_64 Linux and aarch64 Linux,
+        #  but it is the same for a 32 Bit and a 64 Bit Python on Windows!
+        # ... platform.architecture()
+        #  This one is also different for a 32 Bit and a 64 Bit Python on Windows,
+        #  but it is the same for x86_64 Linux and aarch64 Linux!
+        platforms = None
+        if sysconfig_platform != sysconfig.get_platform():
+            # Relevant for the following use cases, for example:
+            # - using a 32 Bit Python on a 64 Bit Windows
+            # - using an emulated aarch Python on an x86_64 Linux
+            output = self.run_python_script(GET_PLATFORMS)
+            platforms = json.loads(output)
+
         return [
-            *(cpython_tags(python) if interpreter_name == "cp" else generic_tags()),
-            *compatible_tags(python, interpreter=interpreter),
+            *(
+                cpython_tags(python, platforms=platforms)
+                if interpreter_name == "cp"
+                else generic_tags(platforms=platforms)
+            ),
+            *compatible_tags(python, interpreter=interpreter, platforms=platforms),
         ]
 
     def get_marker_env(self) -> dict[str, Any]:

tests/utils/env/test_env.py

@@ -9,6 +9,7 @@
 from threading import Thread
 from typing import TYPE_CHECKING
 
+import packaging.tags
 import pytest
 
 from deepdiff.diff import DeepDiff
@@ -92,16 +93,27 @@ def test_env_commands_with_spaces_in_their_arg_work_as_expected(
     assert re.match(r"pip \S+ from", output)
 
 
+@pytest.mark.parametrize("differing_platform", [True, False])
 def test_env_get_supported_tags_matches_inside_virtualenv(
-    tmp_path: Path, manager: EnvManager
+    tmp_path: Path, manager: EnvManager, mocker: MockerFixture, differing_platform: bool
 ) -> None:
     venv_path = tmp_path / "Virtual Env"
     manager.build_venv(venv_path)
     venv = VirtualEnv(venv_path)
 
-    import packaging.tags
+    run_python_script_spy = mocker.spy(venv, "run_python_script")
+
+    # determine expected tags before patching sysconfig!
+    expected_tags = list(packaging.tags.sys_tags())
+
+    if differing_platform:
+        mocker.patch("sysconfig.get_platform", return_value="some_other_platform")
+        expected_call_count = 2
+    else:
+        expected_call_count = 1
 
-    assert venv.get_supported_tags() == list(packaging.tags.sys_tags())
+    assert venv.get_supported_tags() == expected_tags
+    assert run_python_script_spy.call_count == expected_call_count
 
 
 @pytest.mark.skipif(os.name == "nt", reason="Symlinks are not support for Windows")