site: error on sitecustomize import error

Issue #26099: The site module now writes an error into stderr if sitecustomize
module can be imported but executing the module raise an ImportError. Same
change for usercustomize.

2 files changed, 18 insertions, 6 deletions

diff --git a/Lib/site.py b/Lib/site.py
index 3a8d1c3..13ec8fa 100644
--- a/Lib/site.py
+++ b/Lib/site.py
@@ -504,9 +504,13 @@ def venv(known_paths):
 def execsitecustomize():
     """Run custom site specific code, if available."""
     try:
-        import sitecustomize
-    except ImportError:
-        pass
+        try:
+            import sitecustomize
+        except ImportError as exc:
+            if exc.name == 'sitecustomize':
+                pass
+            else:
+                raise
     except Exception as err:
         if os.environ.get("PYTHONVERBOSE"):
             sys.excepthook(*sys.exc_info())
@@ -520,9 +524,13 @@ def execsitecustomize():
 def execusercustomize():
     """Run custom user specific code, if available."""
     try:
-        import usercustomize
-    except ImportError:
-        pass
+        try:
+            import usercustomize
+        except ImportError as exc:
+            if exc.name == 'usercustomize':
+                pass
+            else:
+                raise
     except Exception as err:
         if os.environ.get("PYTHONVERBOSE"):
             sys.excepthook(*sys.exc_info())
diff --git a/Misc/NEWS b/Misc/NEWS
index 01e933c..4e3cc96 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -146,6 +146,10 @@ Core and Builtins
 Library
 -------
 
+- Issue #26099: The site module now writes an error into stderr if
+  sitecustomize module can be imported but executing the module raise an
+  ImportError. Same change for usercustomize.
+
 - Issue #26147: xmlrpc now works with strings not encodable with used
   non-UTF-8 encoding.