Fix the isolation of build env (#478)

news/477.bugfix.md

@@ -0,0 +1 @@
+Fix a bug that build environment is not fully isolated with the hosted environment.

pdm/builders/base.py

@@ -99,23 +99,21 @@ def __init__(self, executable: str, path: str) -> None:
         with open(os.path.join(self.site_dir, "sitecustomize.py"), "w") as fp:
             fp.write(
                 textwrap.dedent(
-                    """
+                    f"""
                 import sys, os, site
 
                 original_sys_path = sys.path[:]
                 known_paths = set()
                 site.addusersitepackages(known_paths)
                 site.addsitepackages(known_paths)
-                known_paths = {{os.path.normpath(p) for p in known_paths}}
+                known_paths = {{os.path.normcase(p) for p in known_paths}}
                 original_sys_path = [
                     p for p in original_sys_path
-                    if os.path.normpath(p) not in known_paths]
+                    if os.path.normcase(p) not in known_paths]
                 sys.path[:] = original_sys_path
-                for lib_path in {lib_paths!r}:
+                for lib_path in {self.lib_dirs!r}:
                     site.addsitedir(lib_path)
-                """.format(
-                        lib_paths=self.lib_dirs
-                    )
+                """
                 )
             )
 

pdm/cli/actions.py

@@ -493,7 +493,11 @@ def version_matcher(py_version: PythonInfo) -> bool:
         )
     )
     project.python = selected_python
-    if old_path and Path(old_path) != Path(new_path) and not project.is_global:
+    if (
+        old_path
+        and Path(old_path) != Path(new_path)
+        and not project.environment.is_global
+    ):
         project.core.ui.echo(termui.cyan("Updating executable scripts..."))
         project.environment.update_shebangs(new_path)
 

pdm/utils.py

@@ -445,7 +445,7 @@ def find_python_in_path(path: os.PathLike) -> Path | None:
     - A valid path to the interpreter
     - A Python root directory that contains the interpreter
     """
-    pathlib_path = Path(path).absolute()
+    pathlib_path = Path(path).resolve()
     if pathlib_path.is_file():
         return pathlib_path
 

tests/test_utils.py

@@ -52,7 +52,10 @@ def test_expend_env_vars_in_auth(given, expected, monkeypatch):
 
 def test_find_python_in_path(tmp_path):
 
-    assert utils.find_python_in_path(sys.executable) == pathlib.Path(sys.executable)
+    assert (
+        utils.find_python_in_path(sys.executable)
+        == pathlib.Path(sys.executable).resolve()
+    )
 
     posix_path_to_executable = pathlib.Path(sys.executable).as_posix().lower()
     if sys.platform == "darwin":