fix the documentation and the error message of modpath_from_file (pylint-dev#2532)

The doc should clarify that the search will always include sys.path. The error message should reflect the actual paths used for checking.

Author: temyurchenko

astroid/modutils.py

@@ -292,7 +292,9 @@ def modpath_from_file_with_callback(
  return modpath
 
  raise ImportError(
- "Unable to find module for {} in {}".format(filename, ", \n".join(sys.path))
+ "Unable to find module for {} in {}".format(
+ filename, ", \n".join(paths_to_check)
+ )
  )
 
 
@@ -305,8 +307,8 @@ def modpath_from_file(filename: str, path: Sequence[str] | None = None) -> list[
  :param filename: file's path for which we want the module's name
 
  :type Optional[List[str]] path:
- Optional list of path where the module or package should be
- searched (use sys.path if nothing or None is given)
+ Optional list of paths where the module or package should be
+ searched, additionally to sys.path
 
  :raise ImportError:
  if the corresponding module's name has not been found