Set sys path technique to raw by default. Fixes #674.

CHANGES.rst

@@ -2,6 +2,25 @@
 CHANGES
 =======
 
+v25.0.0
+-------
+
+* #674: Default ``sys.path`` manipulation by easy-install.pth
+  is now "raw", meaning that when writing easy-install.pth
+  during any install operation, the ``sys.path`` will not be
+  rewritten, giving preference to easy_installed packages.
+
+  To retain the old behavior when using any easy_install
+  operation (including ``setup.py install`` when setuptools is
+  present), set the environment variable:
+
+    SETUPTOOLS_SYS_PATH_TECHNIQUE=rewrite
+
+  This project hopes that that few if any environments find it
+  necessary to retain the old behavior, and intends to drop
+  support for it altogether in a future release. Please report
+  any relevant concerns in the ticket for this change.
+
 v24.3.1
 -------
 

setuptools/command/easy_install.py

@@ -1661,7 +1661,7 @@ class RewritePthDistributions(PthDistributions):
         """)
 
 
-if os.environ.get('SETUPTOOLS_SYS_PATH_TECHNIQUE', 'rewrite') == 'rewrite':
+if os.environ.get('SETUPTOOLS_SYS_PATH_TECHNIQUE', 'raw') == 'rewrite':
     PthDistributions = RewritePthDistributions