Fix handling of the metadata and Python resolution

src/hatch/env/virtual.py

@@ -18,6 +18,7 @@
 if TYPE_CHECKING:
     from collections.abc import Iterable
 
+    from packaging.specifiers import SpecifierSet
     from virtualenv.discovery.py_info import PythonInfo
 
     from hatch.python.core import PythonManager
@@ -210,7 +211,7 @@ def get_interpreter_resolver_env(self) -> dict[str, str]:
             return env
 
         internal_path = os.pathsep.join(python_dirs)
-        old_path = os.environ.pop('PATH', None)
+        old_path = env.pop('PATH', None)
         env['PATH'] = internal_path if old_path is None else f'{old_path}{os.pathsep}{internal_path}'
 
         return env
@@ -231,7 +232,7 @@ def _interpreter_is_compatible(self, interpreter: PythonInfo) -> bool:
         return (
             interpreter.executable
             and self._is_stable_path(interpreter.executable)
-            and self.metadata.core.python_constraint.contains(interpreter.version_str)
+            and self._python_constraint.contains(interpreter.version_str)
         )
 
     def _get_concrete_interpreter_path(self, python_version: str = '') -> str | None:
@@ -349,6 +350,16 @@ def _python_resolvers(self) -> dict[str, Callable[[str], str | None]]:
             'internal': self._resolve_internal_interpreter_path,
         }
 
+    @cached_property
+    def _python_constraint(self) -> SpecifierSet:
+        from packaging.specifiers import SpecifierSet
+
+        from hatch.utils.metadata import get_project_metadata
+
+        project_metadata = get_project_metadata(self)
+
+        return SpecifierSet(project_metadata['requires-python'])
+
     @contextmanager
     def safe_activation(self):
         # Set user-defined environment variables first so ours take precedence

src/hatch/utils/metadata.py

@@ -0,0 +1,30 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Any
+
+if TYPE_CHECKING:
+    from hatch.env.plugin.interface import EnvironmentInterface
+
+
+def get_project_metadata(environment: EnvironmentInterface) -> dict[str, Any]:
+    from hatchling.dep.core import dependencies_in_sync
+
+    if not environment.metadata.hatch.metadata.hook_config or dependencies_in_sync(
+        environment.metadata.build.requires_complex
+    ):
+        from hatchling.metadata.utils import resolve_metadata_fields
+
+        with environment.root.as_cwd():
+            return resolve_metadata_fields(environment.metadata)
+
+    try:
+        environment.check_compatibility()
+    except Exception as e:
+        environment.app.abort(f'Environment `{environment.name}` is incompatible: {e}')
+
+    import json
+
+    with environment.root.as_cwd(), environment.build_environment(environment.metadata.build.requires):
+        command = ['python', '-u', '-W', 'ignore', '-m', 'hatchling', 'metadata', '--app', '--compact']
+        process = environment.platform.capture_process(command)
+        return json.loads(environment.app.read_builder(process))