narrow exceptions guards in SourceFileLoader.set_data

Author: picnixz

Doc/library/importlib.rst

@@ -621,8 +621,9 @@ ABC hierarchy::
         path. Any intermediate directories which do not exist are to be created
         automatically.
 
-        When writing to the path fails by raising an :class:`OSError`
-        or a :class:`ValueError`, the exception is not propagated.
+        When writing to the path fails because the path is read-only
+        (:const:`errno.EACCES`/:exc:`PermissionError`), do not propagate the
+        exception. Other exceptions should still be propagated.
 
         .. versionchanged:: 3.4
            No longer raises :exc:`NotImplementedError` when called.

Lib/importlib/_bootstrap_external.py

@@ -1259,15 +1259,15 @@ def set_data(self, path, data, *, _mode=0o666):
             except FileExistsError:
                 # Probably another Python process already created the dir.
                 continue
-            except (OSError, ValueError) as exc:
-                # Could be a permission error, read-only filesystem, or
-                # an invalid path name: just forget about writing the data.
+            except PermissionError as exc:
+                # Could be a permission error, read-only filesystem:
+                # just forget about writing the data.
                 _bootstrap._verbose_message('could not create {!r}: {!r}',
                                             parent, exc)
                 return
         try:
             _write_atomic(path, data, _mode)
-        except (OSError, ValueError) as exc:
+        except PermissionError as exc:
             # Same as above: just don't write the bytecode.
             _bootstrap._verbose_message('could not create {!r}: {!r}', path,
                                         exc)