Use osx_framework_user for Mac framework build

Author: uranusjr

news/9844.bugfix.rst

@@ -0,0 +1 @@
+Fix ``--user`` install scheme selection for macOS framework build.

src/pip/_internal/locations/_sysconfig.py

@@ -54,7 +54,10 @@ def _infer_prefix():
 def _infer_user():
     # type: () -> str
     """Try to find a user scheme for the current platform."""
-    suffixed = f"{os.name}_user"
+    if sysconfig.get_config_var("PYTHONFRAMEWORK"):  # Mac framework build.
+        suffixed = "osx_framework_user"
+    else:
+        suffixed = f"{os.name}_user"
     if suffixed in _AVAILABLE_SCHEMES:
         return suffixed
     if "posix_user" not in _AVAILABLE_SCHEMES:  # User scheme unavailable.