general refactor (#759)

eolearn/core/utils/parallelize.py

@@ -49,9 +49,7 @@ def _decide_processing_type(workers: int | None, multiprocess: bool) -> _Process
     """
     if workers == 1:
         return _ProcessingType.SINGLE_PROCESS
-    if multiprocess:
-        return _ProcessingType.MULTIPROCESSING
-    return _ProcessingType.MULTITHREADING
+    return _ProcessingType.MULTIPROCESSING if multiprocess else _ProcessingType.MULTITHREADING
 
 
 def parallelize(
@@ -74,10 +72,7 @@ def parallelize(
     :return: A list of function results.
     """
     if not params:
-        raise ValueError(
-            "At least 1 list of parameters should be given. Otherwise it is not clear how many times the"
-            "function has to be executed."
-        )
+        return []
     processing_type = _decide_processing_type(workers=workers, multiprocess=multiprocess)
 
     if processing_type is _ProcessingType.SINGLE_PROCESS:
@@ -105,7 +100,6 @@ def execute_with_mp_lock(function: Callable[..., OutputType], *args: Any, **kwar
     :param function: A function
     :param args: Function's positional arguments
     :param kwargs: Function's keyword arguments
-    :return: Function's results
     """
     if multiprocessing.current_process().name == "MainProcess" or MULTIPROCESSING_LOCK is None:
         return function(*args, **kwargs)
@@ -165,10 +159,7 @@ def join_futures_iter(
     """
 
     def _wait_function(remaining_futures: Collection[Future]) -> tuple[Collection[Future], Collection[Future]]:
-        done, not_done = concurrent.futures.wait(
-            remaining_futures, timeout=float(update_interval), return_when=FIRST_COMPLETED
-        )
-        return done, not_done
+        return concurrent.futures.wait(remaining_futures, timeout=float(update_interval), return_when=FIRST_COMPLETED)
 
     def _get_result(future: Future) -> Any:
         return future.result()
@@ -184,8 +175,6 @@ def _base_join_futures_iter(
 ) -> Generator[tuple[int, OutputType], None, None]:
     """A generalized utility function that resolves futures, monitors progress, and serves as an iterator over
     results."""
-    if not isinstance(futures, list):
-        raise ValueError(f"Parameters 'futures' should be a list but {type(futures)} was given")
     remaining_futures: Collection[FutureType] = _make_copy_and_empty_given(futures)
 
     id_to_position_map = {id(future): index for index, future in enumerate(remaining_futures)}
@@ -195,9 +184,8 @@ def _base_join_futures_iter(
             done, remaining_futures = wait_function(remaining_futures)
             for future in done:
                 result = get_result_function(future)
-                result_position = id_to_position_map[id(future)]
                 pbar.update(1)
-                yield result_position, result
+                yield id_to_position_map[id(future)], result
 
 
 def _make_copy_and_empty_given(items: list[T]) -> list[T]: